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Changfeng Tai - One of the best experts on this subject based on the ideXlab platform.

  • superficial peroneal neuromodulation of persistent bladder underactivity induced by prolonged pudendal Afferent nerve stimulation in cats
    American Journal of Physiology-regulatory Integrative and Comparative Physiology, 2021
    Co-Authors: Jialiang Chen, William C De Groat, Bing Shen, Jicheng Wang, Anand Mohapatra, Jun Zhao, Yihua Zhong, Zhijun Shen, Jonathan M Beckel, Changfeng Tai
    Abstract:

    The purpose of this study is to determine if superficial peroneal nerve stimulation (SPNS) can reverse persistent bladder underactivity induced by prolonged pudendal nerve stimulation (PNS). In 16 α-chloralose anesthetized cats, PNS and SPNS were applied by nerve cuff electrodes. Skin surface electrodes were also used for SPNS. Bladder underactivity consisting of a significant increase in bladder capacity to 157.8±10.9% of control and a significant reduction in bladder contraction amplitude to 56.0±5.0% of control was induced by repetitive (4-16 times) application of 30-min PNS. SPNS (1 Hz, 0.2 ms) at 1.5 to 2 times threshold intensity (T) for inducing posterior thigh muscle contractions was applied either continuously (SPNSc) or intermittently (SPNSi) during a cystometrogram (CMG) to determine if the stimulation can reverse the PNS-induced bladder underactivity. SPNSc or SPNSi applied by nerve cuff electrodes during the prolonged PNS inhibition significantly reduced bladder capacity to 124.4±10.7% and 132.4±14.2% of control, respectively, and increased contraction amplitude to 85.3±6.2% and 75.8±4.7%, respectively. Transcutaneous SPNSc and SPNSi also significantly reduced bladder capacity and increased contraction amplitude. Additional PNS applied during the bladder underactivity further increased bladder capacity, while SPNSc applied simultaneously with the PNS reversed the increase in bladder capacity. This study indicates that a non-invasive superficial peroneal neuromodulation therapy might be developed to treat bladder underactivity caused by abnormal pudendal nerve Somatic Afferent activation that is hypothesized to occur in patients with Fowler's syndrome.

  • bladder underactivity after prolonged stimulation of Somatic Afferent axons in the tibial nerve in cats
    Neurourology and Urodynamics, 2018
    Co-Authors: Katherine Theisen, William C De Groat, James R Roppolo, Jeffery Browning, Bing Shen, Jicheng Wang, Changfeng Tai
    Abstract:

    AIMS To establish an animal model of bladder underactivity induced by prolonged and intense stimulation of Somatic Afferent axons in the tibial nerve. METHODS In seven cats under α-chloralose anesthesia, tibial nerve stimulation (TNS) of 30-min duration was repeatedly (3-8 times) applied at 4-6 times threshold (T) intensity for inducing a toe twitch to produce bladder underactivity determined by cystometry. Naloxone (1 mg/kg, i.v.) was administered to examine the role of opioid receptors in TNS-induced bladder underactivity. RESULTS After prolonged (1.5-4 h) and intense (4-6T) TNS, a complete suppression of the micturition reflex occurred in six cats and an increase in bladder capacity to about 150% of control and a decrease in the micturition contraction amplitude to 50% of control occurred in one cat. The bladder underactivity was maintained for at least 1-1.5 h. Naloxone reversed the bladder underactivity, but an additional 30-min TNS removed the naloxone effect. CONCLUSIONS The results indicate that prolonged and intense activation of Somatic Afferent axons in the tibial nerve can suppress the central reflex mechanisms controlling micturition. This animal model may be useful for examining the pathophysiology of neurogenic bladder underactivity and for development of new treatments for underactive bladder symptoms.

  • transcutaneous electrical stimulation of Somatic Afferent nerves in the foot relieved symptoms related to postoperative bladder spasms
    BMC Urology, 2017
    Co-Authors: Chanjuan Zhang, Zhiying Xiao, Xiulin Zhang, Liqiang Guo, Wendong Sun, Changfeng Tai, Zhaoqun Jiang, Yuqiang Liu
    Abstract:

    Bladder spasm is a common side effect of urological surgery. Main treatment modalities include opioids or anticholinergic medication; however, bladder spasms still occur even after these interventions. Recent studies indicate that transcutaneous stimulation of the foot can result in 50% increase in bladder capacity in healthy adults, and inhibit bladder detrusor overactivity in spinal cord injured patients. In this study, we examined the effects of transcutaneous electrical stimulation of the foot on bladder spasms related symptoms. Sixty-six male patients who underwent prostate or bladder surgeries due to benign prostatic hyperplasia or bladder diseases were randomly divided into two groups: the control group (n = 36) and the treatment group (n = 30). The control group received the routine postoperative care. The treatment group received daily transcutaneous electrical stimulation of the foot during 3 days after surgery; each time lasted for 60 min. All patients were evaluated by the Visual Analogue Scale for pain sensation, frequency of bladder spasm episodes, and a total score of bladder spasms symptoms. In the control group, the patients with bladder surgery had a higher Visual Analogue Scale score than patients with prostate surgery (P = 0.024). In both treatment and control groups, the Visual Analogue Scale score, spasm frequency, and total score of bladder spasm symptoms decreased from day 1 to day 3 (P <0.001). The Visual Analogue Scale score at day 2, total score of bladder spasm symptoms at day 2 and day 3 were significantly lower in the treatment group than in the control group (P <0.05). These results provided preliminary evidence suggesting beneficial effects of stimulating Somatic Afferent nerves in the foot on postoperative bladder spasms. The study was registered with Chinese Clinical Trial Registry on June 13 2016 ( http://www.chictr.org.cn/ ) (Identifier: ChiCTR-INR-16008635)

  • Transcutaneous electrical stimulation of Somatic Afferent nerves in the foot relieved symptoms related to postoperative bladder spasms
    BMC, 2017
    Co-Authors: Chanjuan Zhang, Zhiying Xiao, Xiulin Zhang, Liqiang Guo, Wendong Sun, Changfeng Tai, Zhaoqun Jiang, Yuqiang Liu
    Abstract:

    Abstract Background Bladder spasm is a common side effect of urological surgery. Main treatment modalities include opioids or anticholinergic medication; however, bladder spasms still occur even after these interventions. Recent studies indicate that transcutaneous stimulation of the foot can result in 50% increase in bladder capacity in healthy adults, and inhibit bladder detrusor overactivity in spinal cord injured patients. In this study, we examined the effects of transcutaneous electrical stimulation of the foot on bladder spasms related symptoms. Methods Sixty-six male patients who underwent prostate or bladder surgeries due to benign prostatic hyperplasia or bladder diseases were randomly divided into two groups: the control group (n = 36) and the treatment group (n = 30). The control group received the routine postoperative care. The treatment group received daily transcutaneous electrical stimulation of the foot during 3 days after surgery; each time lasted for 60 min. All patients were evaluated by the Visual Analogue Scale for pain sensation, frequency of bladder spasm episodes, and a total score of bladder spasms symptoms. Results In the control group, the patients with bladder surgery had a higher Visual Analogue Scale score than patients with prostate surgery (P = 0.024). In both treatment and control groups, the Visual Analogue Scale score, spasm frequency, and total score of bladder spasm symptoms decreased from day 1 to day 3 (P 

  • differential role of opioid receptors in tibial nerve inhibition of nociceptive and nonnociceptive bladder reflexes in cats
    American Journal of Physiology-renal Physiology, 2012
    Co-Authors: Changfeng Tai, James R Roppolo, Bing Shen, Jicheng Wang, Guoqing Chen, Dafe P Ogagan, Jeffrey Larson, William C De Groat
    Abstract:

    Naloxone (an opioid receptor antagonist) was used to examine the role of opioid mechanisms in bladder reflexes and in Somatic Afferent inhibition of these reflexes by tibial nerve stimulation (TNS)...

William C De Groat - One of the best experts on this subject based on the ideXlab platform.

  • superficial peroneal neuromodulation of persistent bladder underactivity induced by prolonged pudendal Afferent nerve stimulation in cats
    American Journal of Physiology-regulatory Integrative and Comparative Physiology, 2021
    Co-Authors: Jialiang Chen, William C De Groat, Bing Shen, Jicheng Wang, Anand Mohapatra, Jun Zhao, Yihua Zhong, Zhijun Shen, Jonathan M Beckel, Changfeng Tai
    Abstract:

    The purpose of this study is to determine if superficial peroneal nerve stimulation (SPNS) can reverse persistent bladder underactivity induced by prolonged pudendal nerve stimulation (PNS). In 16 α-chloralose anesthetized cats, PNS and SPNS were applied by nerve cuff electrodes. Skin surface electrodes were also used for SPNS. Bladder underactivity consisting of a significant increase in bladder capacity to 157.8±10.9% of control and a significant reduction in bladder contraction amplitude to 56.0±5.0% of control was induced by repetitive (4-16 times) application of 30-min PNS. SPNS (1 Hz, 0.2 ms) at 1.5 to 2 times threshold intensity (T) for inducing posterior thigh muscle contractions was applied either continuously (SPNSc) or intermittently (SPNSi) during a cystometrogram (CMG) to determine if the stimulation can reverse the PNS-induced bladder underactivity. SPNSc or SPNSi applied by nerve cuff electrodes during the prolonged PNS inhibition significantly reduced bladder capacity to 124.4±10.7% and 132.4±14.2% of control, respectively, and increased contraction amplitude to 85.3±6.2% and 75.8±4.7%, respectively. Transcutaneous SPNSc and SPNSi also significantly reduced bladder capacity and increased contraction amplitude. Additional PNS applied during the bladder underactivity further increased bladder capacity, while SPNSc applied simultaneously with the PNS reversed the increase in bladder capacity. This study indicates that a non-invasive superficial peroneal neuromodulation therapy might be developed to treat bladder underactivity caused by abnormal pudendal nerve Somatic Afferent activation that is hypothesized to occur in patients with Fowler's syndrome.

  • bladder underactivity after prolonged stimulation of Somatic Afferent axons in the tibial nerve in cats
    Neurourology and Urodynamics, 2018
    Co-Authors: Katherine Theisen, William C De Groat, James R Roppolo, Jeffery Browning, Bing Shen, Jicheng Wang, Changfeng Tai
    Abstract:

    AIMS To establish an animal model of bladder underactivity induced by prolonged and intense stimulation of Somatic Afferent axons in the tibial nerve. METHODS In seven cats under α-chloralose anesthesia, tibial nerve stimulation (TNS) of 30-min duration was repeatedly (3-8 times) applied at 4-6 times threshold (T) intensity for inducing a toe twitch to produce bladder underactivity determined by cystometry. Naloxone (1 mg/kg, i.v.) was administered to examine the role of opioid receptors in TNS-induced bladder underactivity. RESULTS After prolonged (1.5-4 h) and intense (4-6T) TNS, a complete suppression of the micturition reflex occurred in six cats and an increase in bladder capacity to about 150% of control and a decrease in the micturition contraction amplitude to 50% of control occurred in one cat. The bladder underactivity was maintained for at least 1-1.5 h. Naloxone reversed the bladder underactivity, but an additional 30-min TNS removed the naloxone effect. CONCLUSIONS The results indicate that prolonged and intense activation of Somatic Afferent axons in the tibial nerve can suppress the central reflex mechanisms controlling micturition. This animal model may be useful for examining the pathophysiology of neurogenic bladder underactivity and for development of new treatments for underactive bladder symptoms.

  • electrical stimulation of Somatic Afferent nerves in the foot increases bladder capacity in healthy human subjects
    The Journal of Urology, 2014
    Co-Authors: Mang L Chen, Bing Shen, James R Roppolo, Christopher Chermansky, William C De Groat
    Abstract:

    Purpose: We determined whether electrical stimulation of Somatic Afferent nerves in the foot could delay bladder filling sensations and increase bladder capacity in healthy humans without overactive bladder.Materials and Methods: Eight subjects underwent 90-minute foot stimulation using skin surface electrodes connected to a transcutaneous electrical nerve stimulator. The electrodes were attached to the bottom of the foot. Subjects completed a 3-day voiding diary, during which foot stimulation was applied on day 2. Stimulation parameters were pulse frequency 5 Hz, rectangular waveform pulse width 0.2 milliseconds and intensity 2 to 6 times the minimal stimulation current necessary to induce toe twitch. Stimulation intensity was set by each subject to a maximal level without causing discomfort. Subjects were provided with 500 to 1,000 ml of water to drink during stimulation.Results: Average ± SE volume per void was 350 ± 22 ml during the 24 hours before foot stimulation. This voided volume increased to a m...

  • differential role of opioid receptors in tibial nerve inhibition of nociceptive and nonnociceptive bladder reflexes in cats
    American Journal of Physiology-renal Physiology, 2012
    Co-Authors: Changfeng Tai, James R Roppolo, Bing Shen, Jicheng Wang, Guoqing Chen, Dafe P Ogagan, Jeffrey Larson, William C De Groat
    Abstract:

    Naloxone (an opioid receptor antagonist) was used to examine the role of opioid mechanisms in bladder reflexes and in Somatic Afferent inhibition of these reflexes by tibial nerve stimulation (TNS)...

  • post stimulation inhibitory effect on reflex bladder activity induced by activation of Somatic Afferent nerves in the foot
    The Journal of Urology, 2012
    Co-Authors: William C De Groat, James R Roppolo, Bing Shen, Jicheng Wang, Guoqing Chen, Jeffrey A Larson, Dafe P Ogagan, Changfeng Tai
    Abstract:

    Purpose: We determined whether transcutaneous electrical stimulation of Somatic Afferent nerves in the foot of cats would induce a post-stimulation increase in bladder capacity.Materials and Methods: In 12 α-chloralose anesthetized cats electrical stimulation (5 Hz) was applied to the skin of the hind foot for 2, 30-minute periods via dual pad electrodes attached on the plantar and dorsal surfaces (combination 1 and 2) or at 2 sites on the plantar surface (combination 1 and 3). The post-stimulation effect was examined by repeat cystometrogram after 30-minute stimulation. In the control group of 12 cats isovolumetric contractions were allowed to continue during each 30-minute period without stimulation.Results: Stimulation inhibited isovolumetric rhythmic bladder contractions. Bladder capacity was not increased after the first 30-minute foot stimulation via electrodes 1 and 2 but it was significantly increased a mean ± SE of 47.5% ± 2.9% after the second 30-minute stimulation via electrodes 1 and 3. After ...

James R Roppolo - One of the best experts on this subject based on the ideXlab platform.

  • bladder underactivity after prolonged stimulation of Somatic Afferent axons in the tibial nerve in cats
    Neurourology and Urodynamics, 2018
    Co-Authors: Katherine Theisen, William C De Groat, James R Roppolo, Jeffery Browning, Bing Shen, Jicheng Wang, Changfeng Tai
    Abstract:

    AIMS To establish an animal model of bladder underactivity induced by prolonged and intense stimulation of Somatic Afferent axons in the tibial nerve. METHODS In seven cats under α-chloralose anesthesia, tibial nerve stimulation (TNS) of 30-min duration was repeatedly (3-8 times) applied at 4-6 times threshold (T) intensity for inducing a toe twitch to produce bladder underactivity determined by cystometry. Naloxone (1 mg/kg, i.v.) was administered to examine the role of opioid receptors in TNS-induced bladder underactivity. RESULTS After prolonged (1.5-4 h) and intense (4-6T) TNS, a complete suppression of the micturition reflex occurred in six cats and an increase in bladder capacity to about 150% of control and a decrease in the micturition contraction amplitude to 50% of control occurred in one cat. The bladder underactivity was maintained for at least 1-1.5 h. Naloxone reversed the bladder underactivity, but an additional 30-min TNS removed the naloxone effect. CONCLUSIONS The results indicate that prolonged and intense activation of Somatic Afferent axons in the tibial nerve can suppress the central reflex mechanisms controlling micturition. This animal model may be useful for examining the pathophysiology of neurogenic bladder underactivity and for development of new treatments for underactive bladder symptoms.

  • electrical stimulation of Somatic Afferent nerves in the foot increases bladder capacity in healthy human subjects
    The Journal of Urology, 2014
    Co-Authors: Mang L Chen, Bing Shen, James R Roppolo, Christopher Chermansky, William C De Groat
    Abstract:

    Purpose: We determined whether electrical stimulation of Somatic Afferent nerves in the foot could delay bladder filling sensations and increase bladder capacity in healthy humans without overactive bladder.Materials and Methods: Eight subjects underwent 90-minute foot stimulation using skin surface electrodes connected to a transcutaneous electrical nerve stimulator. The electrodes were attached to the bottom of the foot. Subjects completed a 3-day voiding diary, during which foot stimulation was applied on day 2. Stimulation parameters were pulse frequency 5 Hz, rectangular waveform pulse width 0.2 milliseconds and intensity 2 to 6 times the minimal stimulation current necessary to induce toe twitch. Stimulation intensity was set by each subject to a maximal level without causing discomfort. Subjects were provided with 500 to 1,000 ml of water to drink during stimulation.Results: Average ± SE volume per void was 350 ± 22 ml during the 24 hours before foot stimulation. This voided volume increased to a m...

  • differential role of opioid receptors in tibial nerve inhibition of nociceptive and nonnociceptive bladder reflexes in cats
    American Journal of Physiology-renal Physiology, 2012
    Co-Authors: Changfeng Tai, James R Roppolo, Bing Shen, Jicheng Wang, Guoqing Chen, Dafe P Ogagan, Jeffrey Larson, William C De Groat
    Abstract:

    Naloxone (an opioid receptor antagonist) was used to examine the role of opioid mechanisms in bladder reflexes and in Somatic Afferent inhibition of these reflexes by tibial nerve stimulation (TNS)...

  • post stimulation inhibitory effect on reflex bladder activity induced by activation of Somatic Afferent nerves in the foot
    The Journal of Urology, 2012
    Co-Authors: William C De Groat, James R Roppolo, Bing Shen, Jicheng Wang, Guoqing Chen, Jeffrey A Larson, Dafe P Ogagan, Changfeng Tai
    Abstract:

    Purpose: We determined whether transcutaneous electrical stimulation of Somatic Afferent nerves in the foot of cats would induce a post-stimulation increase in bladder capacity.Materials and Methods: In 12 α-chloralose anesthetized cats electrical stimulation (5 Hz) was applied to the skin of the hind foot for 2, 30-minute periods via dual pad electrodes attached on the plantar and dorsal surfaces (combination 1 and 2) or at 2 sites on the plantar surface (combination 1 and 3). The post-stimulation effect was examined by repeat cystometrogram after 30-minute stimulation. In the control group of 12 cats isovolumetric contractions were allowed to continue during each 30-minute period without stimulation.Results: Stimulation inhibited isovolumetric rhythmic bladder contractions. Bladder capacity was not increased after the first 30-minute foot stimulation via electrodes 1 and 2 but it was significantly increased a mean ± SE of 47.5% ± 2.9% after the second 30-minute stimulation via electrodes 1 and 3. After ...

  • suppression of bladder overactivity by activation of Somatic Afferent nerves in the foot
    BJUI, 2011
    Co-Authors: Changfeng Tai, James R Roppolo, Bing Shen, Jicheng Wang, Mang Chen, Hailong Liu, William C De Groat
    Abstract:

    What’s known on the subject? and What does the study add? It is known that electrical stimulation of the sacral root, pudendal nerve, or tibial nerve can inhibit bladder overactivity. These stimulation methods require surgery or repeated clinical visits that are expensive and inconvenient. This study shows for the first time that electrical stimulation of the foot can suppress bladder overactivity. Stimulation of the foot is non-invasive, easily accessible, and convenient, which could be a widely acceptable treatment for bladder overactivity. OBJECTIVE To investigate the possibility of suppressing bladder overactivity by electrical activation of Somatic Afferent nerves in the foot. MATERIALS AND METHODS Cats with an intact spinal cord were studied under α-chloralose anaesthesia. Bladder pressure was recorded via a urethral catheter. Foot stimulation was applied via surface pad electrodes attached to the skin of the front or hind foot. RESULTS Reflex micturition was inhibited by electrical stimulation of the hind foot at either low (5 Hz) or high (20 Hz) frequencies, but stimulation of the front foot was ineffective. The mean (sem) bladder capacity during a saline infusion cystometrogram (CMG) was significantly (P < 0.05) increased to 153.2 (18.2)% and 136.9 (14.3)% of the control bladder capacity by stimulation at frequencies of 5 Hz and 20 Hz, respectively. Intravesical infusion of 0.25% acetic acid (AA) induced bladder overactivity and reduced bladder capacity to 20.3 (8.9)% of the control capacity measured during saline infusion. Foot stimulation inhibited the AA-induced bladder overactivity recorded under isovolumetric conditions, and significantly (P < 0.05) increased bladder capacity during AA infusion. However, it only restored the small bladder capacity caused by AA irritation to 40–50% of the control bladder capacity measured during saline infusion. The effect of foot stimulation did not persist after termination of stimulation during repeated CMG tests. CONCLUSIONS This study shows the potential of noninvasive transcutaneous electrical stimulation of Somatic nerves in the foot to inhibit reflex bladder activity and treat overactive bladder symptoms.

Glenn M. Toney - One of the best experts on this subject based on the ideXlab platform.

  • sensory modalities conveyed in the hindlimb Somatic Afferent input to nucleus tractus solitarius
    Journal of Applied Physiology, 2000
    Co-Authors: Glenn M. Toney, Steve Mifflin
    Abstract:

    To determine the Somatic sensory modalities conveyed by hindlimb Somatic Afferent inputs, the discharge of neurons in the nucleus tractus solitarius was recorded in anesthetized rats after electric...

  • Time-dependent inhibition of hindlimb Somatic Afferent transmission within nucleus tractus solitarius: an in vivo intracellular recording study.
    Neuroscience, 1995
    Co-Authors: Glenn M. Toney, Steven W. Mifflin
    Abstract:

    Abstract In a previous study we demonstrated that hindlimb Somatic Afferent stimulation evokes excitatory responses from neurons in nucleus tractus solitarius. When paired electrical stimuli were delivered to hindlimb Somatic Afferents, the unit response to the second stimulus was significantly reduced compared with responses to the first. This temporal response pattern has been termed time-dependent inhibition since responses to the second stimulus recover as the interval separating the first and second stimuli is increased. To examine possible synaptic mechanisms for Somatic Afferent-evoked time-dependent inhibition, intracellular recordings were made from nucleus tractus solitarius neurons in anesthetized, paralysed rats. Skeletal muscle Afferent fibers were activated by electrically stimulating the right tibial nerve in the hindlimb and neuronal responses recorded in the contralateral nucleus of the solitary tract. Time-dependent inhibition of tibial nerve-evoked unit discharge was studied using a conditioning-test stimulation procedure, with the first (conditioning) and second (test) stimuli separated by intervals of 50, 150 and 250 ms. In 49 units that responded to tibial nerve stimulation, 46 were excited and three were inhibited. Among units excited, 25 displayed a unimodal response that had an onset latency of 21.3 ± 5.9 ms. The remaining 21 units responded with a bimodal discharge pattern characterized by both a short-latency and a long-latency response. The onset latency of the early response was 23.7 ± 5.3 ms and was not statistically different from the unimodal response onset latency. The onset latency of the late response was 143 ± 23.9 ms. Conditioning-test stimulation protocols revealed that short-latency tibial nerve-evoked unit responses to test stimuli were significantly reduced when identical conditioning stimuli were delivered 50 ms earlier. In contrast, the long-latency component of the bimodal response was unaffected by conditioning stimuli. Conditioning-test intervals ≥150 ms were without inhibitory effect. Inhibitions observed in this study occurred without significant membrane hyperpolarization. Furthermore, the magnitude (area) and rate of depolarization of evoked excitatory postsynaptic potentials were both significantly reduced, to 50.7 ± 14.2 and 65.5 ± 15.5% of the control, respectively, at the 50 ms conditioning-test interval. In the present study, time-dependent inhibition of neuronal responses elicited by Somatic Afferent inputs to neurons in the nucleus of the solitary tract occurred without membrane hyperpolarization. Similar results have been reported, but only for visceral Afferent inputs. The consistency of membrane responses to Somatic and visceral inputs suggests that a similar synaptic mechanism(s) likely mediates time-dependent inhibition of both classes of Afferent inputs. Thus, time-dependent inhibition, which appears to be a rather stereotype response among neurons in the nucleus of the solitary tract, could provide a mechanism for integrating functionally heterogenous inputs.

  • Time-dependent inhibition of hindlimb Somatic Afferent inputs to nucleus tractus solitarius.
    Journal of Neurophysiology, 1994
    Co-Authors: Glenn M. Toney, Steven W. Mifflin
    Abstract:

    : 1. In the present investigation, experiments were performed in anesthetized, paralyzed rats (n = 40) to 1) identify and characterize responses of nucleus tractus solitarius (NTS) neurons to hindlimb Somatic Afferent inputs; 2) determine if hindlimb Somatic inputs to NTS undergo time-dependent inhibition similar to that observed among visceral Afferent inputs; and 3) determine if Somatic Afferent-evoked NTS unit discharge is altered by activation of baroreceptor Afferent inputs. 2. Extracellular discharge was recorded from single NTS units following electrical stimulation (approximately 500 microA) of the contralateral tibial nerve (TN) (skeletal muscle Afferents), sural nerve (SN) (cutaneous Afferents), and the ipsilateral aortic nerve (AN) (baroreceptor Afferents). To identify possible time-dependent interactions, a paired pulse or conditioning-test stimulation procedure was employed. The activity of NTS neurons was recorded in response to test stimuli delivered to either TN or SN first in the absence and then in the presence of conditioning stimuli delivered to TN, SN, or AN 50, 150, and 250 ms before the test stimuli. 3. The results indicate that among 31 NTS cells activated by Somatic nerve stimulation, 14 (approximately 50%) received convergent inputs from both the TN and SN, 9 responded to TN stimulation only and 2 were activated by SN stimulation only. These cells were not spontaneously active but showed two distinct patterns of evoked discharge. Some had only a short latency, unimodal response that averaged 25.5 +/- 2.0 (SE) ms for TN inputs (n = 21) and 27.9 +/- 2.8 ms for SN inputs (n = 8).(ABSTRACT TRUNCATED AT 250 WORDS)

Akio Sato - One of the best experts on this subject based on the ideXlab platform.

  • single electrical shock of a Somatic Afferent nerve elicits a and c reflex discharges in gastric vagal efferent nerves in anesthetized rats
    Neuroscience Letters, 1996
    Co-Authors: Atsuko Kimura, Akio Sato, Yuko Sato, Atsuko Suzuki
    Abstract:

    Abstract The possibility that single electrical shock stimulation of Somatic Afferent nerves could evoke a reflex response in vagal efferent nerves innervating the stomach was examined using anesthetized, artificially-ventilated rats. A single shock to a hindlimb Afferent nerve (tibial nerve) produced two distinct reflex components in gastric vagal efferent nerves; namely (1) A-reflex discharges with a latency of about 120 ms and a duration of about 200 ms elicited by stimulation of myelinated A Afferent fibers, and (2) C-reflex discharges with a latency of about 360 ms and a duration of about 200 ms elicited by stimulation of unmyelinated C Afferent fibers. A single shock to a first lumbar spinal Afferent nerve produced only a weak reflex component with a latency of about 120 ms and a duration of about 190 ms in gastric vagal efferent nerves. Limb Afferents appear to have stronger central pathways functionally connecting to gastric vagal efferent preganglionic neurons in the brainstem, than do abdominal Afferents.

  • Somatic Afferent regulation of plasma immunoreactive glucagon in anesthetized rats
    Journal of Physiological Sciences, 1994
    Co-Authors: Mieko Kurosawa, Akio Sato, Nobuo Nagai, Kerstin Uvnasmoberg
    Abstract:

    We examined the neural mechanisms of the effect of noxious and innocuous mechanical stimulation of various segmental skin areas on the plasma glucagon concentration. Experiments were performed using chloralose- and urethane-anesthetized rats, ventilated artificially. The cutaneous stimuli of two different modalities, noxious and innocuous mechanical stimuli by pinching and brushing, were delivered to various segmental areas including the face, forelimb for forepaw, abdomen, and hindlimb or hindpaw. Blood samples were collected from the femoral artery, and plasma glucagon was measured by radioimmunoassay. Cutaneous pinching for 3.5 min of the face, forepaw, abdomen, or hindpaw increased the plasma immunoreactive glucagon (IRG), and the increase was larger following pinching of the abdmen or hindpaw than pinching of the face or forepaw. Brushing for 3.5 min of the face, forelimb, abdomen, or hindlimb did not significantly affect the plasma IRG. The increase in plasma IRG following skin pinching was abolished when both parasympathetic vagal and sympathetic nerves to the pancreas were bilaterally severed. The increase in plasma IRG was not abolished after bilateral severance of either the parasympathetic vagal or sympathetic nerves alone. These findings indicate that excitation of cutaneous nociceptive Afferent information from the various spinal segments can regulate glucagon secretion from the pancreas as a reflex response, whose efferent limb is dually composed of both sympathetic and parasympathetic nerves.

  • Somatic Afferent regulation of cytotoxic activity of splenic natural killer cells in anesthetized rats
    Japanese Journal of Physiology, 1994
    Co-Authors: A Kimura, Nobuo Nagai, Akio Sato
    Abstract:

    The effects of non-noxious and noxious mechanical stimulation of the skin on cytotoxic activity of splenic natural killer (NK) cells and splenic blood flow were examined in anesthetized rats. Bilateral brushing of the body surface between the lateral chest and hindlimb for 30 min did not significantly influence cytotoxic activity of splenic NK cells, splenic blood flow or splenic sympathetic efferent nerve activity. Bilateral pinching stimulation of the skin of the hindpaws for 30 min reduced cytotoxic activity of splenic NK cells and splenic blood flow to 67 +/- 8 and 82 +/- 3% of the control values, respectively. Pinching the hindpaws for 30 min increased splenic sympathetic efferent nerve activity to 143 +/- 15% of control. Electrical stimulation (10 V, 10 Hz) of the splanchnic nerve for 20 min produced a decrease in the cytotoxic activity of splenic NK cells and splenic blood flow. The hindpaw pinching-induced suppression of cytotoxic activity of NK cells was abolished after surgical transection of the splenic sympathetic nerve or the spinal cord at the cervical level. These results indicate that the suppression of cytotoxic activity of NK cells and splenic blood flow following noxious pinching stimulation is a supra-spinal reflex response mediated via the splenic sympathetic nerve.

  • Somatic Afferent regulation of plasma prolactin in anesthetized rats
    Japanese Journal of Physiology, 1993
    Co-Authors: Harumi Hotta, Akio Sato, Yuko Sato, Kerstin Uvnasmoberg
    Abstract:

    The effects of noxious and non-noxious mechanical stimulation of various segmental skin areas (face, forelimb, abdomen, and hindlimb) on the plasma concentrations of prolactin (PRL) were examined in anesthetized rats. The experiments were performed on urethane-anesthetized female Wistar rats, ventilated artificially, on the day of estrus. Blood samples (0.5 ml) were collected from the femoral artery every 20 min. Plasma concentrations of PRL were determined by radioimmunoassay. Noxious mechanical stimulation was delivered by pinching the skin with a surgical clamp, while non-noxious mechanical stimulation was delivered by brushing the skin with a toothbrush. Pinching the hindpaw for 6 min significantly increased plasma PRL concentration during stimulation to about 280% of the prestimulation value (p < 0.05). Pinching the face, the forepaw or the abdomen had no significant effect. Brushing of any skin area for 6 min did not significantly change plasma PRL concentrations. These results indicate that cutaneous, nociceptive sensory information contributes to the reflex regulation of PRL secretion from the anterior pituitary when emotional factors are eliminated by anesthesia, and this effect is highly dependent on the site of stimulation.

  • Somatic Afferent regulation of plasma luteinizing hormone and testosterone in anesthetized rats
    Japanese Journal of Physiology, 1992
    Co-Authors: Toru Tsuchiya, Yasuhisa Nakayama, Akio Sato
    Abstract:

    The effects of cutaneous stimulation on plasma luteinizing hormone (LH) and testosterone were examined in adult male Wistar rats anesthetized with pentobarbital. Under the resting condition without Somatic sensory stimulation, plasma LH and testosterone measured every 30 min between 1400 and 1730 h revealed no significant fluctuations. Nociceptive mechanical stimulation of bilateral hindpaws by pinching for 10 min significantly increased plasma LH and testosterone. Plasma LH was increased 30 and 60 min after stimulation, while plasma testosterone was increased 60-150 min after stimulation. However, innocuous mechanical stimulation of bilateral hindlimbs by brushing for 10 min did not significantly change either plasma LH or testosterone. These results indicate that, when emotional factors were eliminated by anesthetization, cutaneous nociceptive information led to the increased secretion of LH from the anterior pituitary, resulting in an increase in testosterone secretion from the testes into the plasma.