The Experts below are selected from a list of 105 Experts worldwide ranked by ideXlab platform
Neil E. Rowland - One of the best experts on this subject based on the ideXlab platform.
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Comparison of fos-like immunoreactivity induced in rat brain by central injection of angiotensin II and carbachol
American Journal of Physiology-Regulatory Integrative and Comparative Physiology, 1994Co-Authors: Neil E. Rowland, A. K. Rozelle, G. C. SmithAbstract:Rats were given intracerebroventricular injections of either angiotensin II (ANG II) or the cholinomimetic carbachol. Some rats received cotreatment with ANG II antagonists selective for either angiotensin receptor AT1 (losartan) or AT2 (PD-123319, CGP-42112A). One hour later, the rats were killed and the brains processed for immunocytochemical detection of Fos-like immunoreactivity (FLI). ANG II treatment induced strong FLI in the anterior subfornical organ (SFO), median preoptic nucleus (MnPO), organum vasculosum laminae terminalis (OVLT), and supraoptic and paraventricular hypothalamic nuclei (SON, PVH). The AT1 antagonist abolished FLI in all regions normally stimulated by ANG II. The AT2 antagonist PD-123319 reduced FLI in SON and PVH, but CGP-42112A was less effective. Carbachol induced strong FLI in SON, PVH, and MnPO and only moderate FLI in SFO and OVLT. The AT1 antagonist prevented carbachol-induced FLI in the MnPO only. The distributions of FLI are compared between these central Dipsogens and with that previously reported after peripheral infusion of ANG II, and their implications for mapping central thirst pathways are discussed.
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Effect of desalivation on water and sodium chloride intake in rats.
Physiology & behavior, 1994Co-Authors: Tana M. Nicholson, Neil E. RowlandAbstract:Abstract Desalivate rats consumed significantly less water than sham-operated rats in response to acute challenges with a variety of Dipsogens, including polyethelene glycol (PEG), isoproterenol, serotonin, and an angiotensin I converting enzyme inhibitor (CEI). Nonsignificant reductions were recorded after treatments with either angiotensin II or hypertonic NaCl. Meal-related hyperdipsia, and resultant possible hyperhydration, of desalivate rats does not account fully for these reductions in experimental thirsts. The mean 24-h intake of three concentrations of NaCl, in choice with water, showed no difference in the preferences for NaCl of desalivate and sham-operated animals. During chronic administration of CEIs, both desalivate and sham-operated rats showed comparable induction of NaCl appetite.
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Induction of hyperhydration in rats by IP loading with graded concentrations of NaCl solution.
Pharmacology biochemistry and behavior, 1993Co-Authors: Melvin J. Fregly, Neil E. Rowland, J. Robert CadeAbstract:Abstract IP loads of NaCl solution (1% of body weight) varying in concentration from 0.15–1.0 M were used to assess their ability to induce hyperhydration in rats that were allowed access to water for 6 h after loading. The hypertonic concentrations (0.25, 0.50, and 1.0 M) increased water intake in a concentration-related fashion. Only loads of 0.50 and 1.0 M NaCl solution increased urine output above that of water-loaded controls. All hypertonic concentrations increased fluid exchange (i.e., water intake less urine output) significantly. There was a direct concentration-related increase in accumulative mean fluid exchange (ΔFE, fluid exchange of NaCl-loaded group less that of control group). There was also a direct concentration-related increase in the time of hyperhydration. When related to each other, ΔFE was a direct linear function of time of hyperhydration. The slope and intercept of this relationship were compared with those found in an earlier study for angiotensin II (AngII) and isoproterenol (ISO), both potent Dipsogens. Comparison revealed that slopes, but not intercepts, of the relationship between ΔFE and time of hyperhydration for any two of the three treatments differed significantly. These data suggest that a given time of hyperhydration can be achieved at a lower ΔFE with NaCl loads than with administration of either AngII or ISO. This suggests, in turn, that loading with NaCl solutions produces a more effective hyperhydration than is achieved with administration of either AngII or ISO.
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Effect of a nonpeptide angiotensin II receptor antagonist, DuP 753, on angiotensin-related water intake in rats☆
Brain research bulletin, 1991Co-Authors: Melvin J. Fregly, Neil E. RowlandAbstract:The effect of peripheral administration of the nonpeptide angiotensin II-1 (AII) receptor blocker, DuP 753, on the Dipsogenic responses to peripherally administered angiotensins I, II, and III was tested. In all cases, DuP 753 significantly inhibited the drinking response, whether administered 15 or 45 minutes prior to administration of the Dipsogen. These results suggest that the drinking responses to angiotensins I, II, and III are mediated by AII-1 receptors. They also suggest that either AIII acts via the AII-1 receptor or that DuP 753 competes at an AIII-sensitive receptor. These studies also showed that when both AII and DuP 753 were given cerebroventricularly (ICV), potent inhibition of the drinking response occurred. Further, when DuP 753 was administered peripherally and AII ICV, drinking was also inhibited. Hence, DuP 753 must penetrate the brain, at least at the circumventricular sites implicated in angiotensin-related drinking. However, centrally administered DuP 753 failed to inhibit the drinking response to peripherally administered AII. This observation is presently unexplained, but may be related to the possibility that centrally administered DuP 753 is inactivated more quickly than when it is administered peripherally. Additional studies will be required to assess this.
Samuel H.h. Chan - One of the best experts on this subject based on the ideXlab platform.
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Functional characterization of caudal hypoglossal neurons by spectral patterns of neuronal discharges in the rat.
Neuroscience, 1997Co-Authors: Cheryl C.h. Yang, Terry B.j. Kuo, Samuel H.h. ChanAbstract:This study evaluated the spectral characteristics of neuronal discharges in the caudal hypoglossal nucleus and their physiological relevance in adult, male Sprague Dawley rats which were anaesthetized and maintained with pentobarbital sodium. Based on auto-spectral analysis of extracellular single-neuron activity, three spectral patterns were identified in the spontaneous discharges of hypoglossal neurons. Neurons that exhibited a rhythmic pattern manifested a concentrated peak in the auto-spectrogram that corresponded to the mean discharge rate. A majority of hypoglossal neurons displayed the modulated pattern, which was manifested either as scattered power densities (wide-band modulated pattern) or with a peak frequency component that was different from the mean discharge rate (narrow-band modulated pattern). Neurons that exhibited a mixed pattern displayed both rhythmic and modulated spectral patterns. Cross-spectral analysis further revealed that respiratory modulation constituted a major physiological influence on caudal hypoglossal neurons. The respiratory modulated pattern, however, could be converted to a mixed pattern in the presence of a central Dipsogen, angiotensin III. The results suggest that the spectral patterns of neuronal discharges in caudal hypoglossal neurons represent manifestations of multiple physiological information, including that regarding respiration and Dipsogenesis, which is encoded in these neurons. It was also shown that this information may only be revealed by auto-spectral and cross-spectral analysis of neuronal discharge signals.
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Central effect of angiotensin III on caudal hypoglossal neurons in rats
American Journal of Physiology-Regulatory Integrative and Comparative Physiology, 1995Co-Authors: Cheryl C.h. Yang, Julie Y.h. Chan, Samuel H.h. ChanAbstract:We communicated the central effect of angiotensin III (ANG III), a potent signal for extracellular dehydration, on single neurons in the caudal hypoglossal nucleus of Sprague-Dawley rats anesthetized with pentobarbital sodium. A significant number (121 of 168) of caudal hypoglossal neurons responded to intracerebroventricular application of ANG III (80 or 160 pmol), with either an increase (n = 83) or decrease (n = 38) in their spontaneous discharge. These effects of ANG III were significantly reversed by intracerebroventricular application of the nonpeptide angiotensin AT1 receptor antagonist losartan (40 nmol), but not by the AT2 antagonist, PD-123319. The hypoglossal neuronal responses to repeated administration of ANG III (80 pmol), delivered at an interval < or = 18 min, exhibited acute tachyphylaxis. Intracerebroventricular administration of the cholinergic Dipsogen, carbachol (50 ng), or the osmotic stimulant, hypertonic saline (0.5 M), also elicited responses in ANG III-responsive hypoglossal neurons. These results suggest that neurons in the caudal hypoglossal nucleus may serve as the final common pathway for extracellular and, possibly, intracellular thirst in the rat. Furthermore, it is likely that the action of ANG III is mediated by the AT1 subtype of angiotensin receptors.
Melvin J. Fregly - One of the best experts on this subject based on the ideXlab platform.
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Induction of hyperhydration in rats by IP loading with graded concentrations of NaCl solution.
Pharmacology biochemistry and behavior, 1993Co-Authors: Melvin J. Fregly, Neil E. Rowland, J. Robert CadeAbstract:Abstract IP loads of NaCl solution (1% of body weight) varying in concentration from 0.15–1.0 M were used to assess their ability to induce hyperhydration in rats that were allowed access to water for 6 h after loading. The hypertonic concentrations (0.25, 0.50, and 1.0 M) increased water intake in a concentration-related fashion. Only loads of 0.50 and 1.0 M NaCl solution increased urine output above that of water-loaded controls. All hypertonic concentrations increased fluid exchange (i.e., water intake less urine output) significantly. There was a direct concentration-related increase in accumulative mean fluid exchange (ΔFE, fluid exchange of NaCl-loaded group less that of control group). There was also a direct concentration-related increase in the time of hyperhydration. When related to each other, ΔFE was a direct linear function of time of hyperhydration. The slope and intercept of this relationship were compared with those found in an earlier study for angiotensin II (AngII) and isoproterenol (ISO), both potent Dipsogens. Comparison revealed that slopes, but not intercepts, of the relationship between ΔFE and time of hyperhydration for any two of the three treatments differed significantly. These data suggest that a given time of hyperhydration can be achieved at a lower ΔFE with NaCl loads than with administration of either AngII or ISO. This suggests, in turn, that loading with NaCl solutions produces a more effective hyperhydration than is achieved with administration of either AngII or ISO.
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Effect of a nonpeptide angiotensin II receptor antagonist, DuP 753, on angiotensin-related water intake in rats☆
Brain research bulletin, 1991Co-Authors: Melvin J. Fregly, Neil E. RowlandAbstract:The effect of peripheral administration of the nonpeptide angiotensin II-1 (AII) receptor blocker, DuP 753, on the Dipsogenic responses to peripherally administered angiotensins I, II, and III was tested. In all cases, DuP 753 significantly inhibited the drinking response, whether administered 15 or 45 minutes prior to administration of the Dipsogen. These results suggest that the drinking responses to angiotensins I, II, and III are mediated by AII-1 receptors. They also suggest that either AIII acts via the AII-1 receptor or that DuP 753 competes at an AIII-sensitive receptor. These studies also showed that when both AII and DuP 753 were given cerebroventricularly (ICV), potent inhibition of the drinking response occurred. Further, when DuP 753 was administered peripherally and AII ICV, drinking was also inhibited. Hence, DuP 753 must penetrate the brain, at least at the circumventricular sites implicated in angiotensin-related drinking. However, centrally administered DuP 753 failed to inhibit the drinking response to peripherally administered AII. This observation is presently unexplained, but may be related to the possibility that centrally administered DuP 753 is inactivated more quickly than when it is administered peripherally. Additional studies will be required to assess this.
Tomoki Naoe - One of the best experts on this subject based on the ideXlab platform.
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a new diagnostic kit odk 1201 for the quantitation of low major bcr abl mrna level in chronic myeloid leukemia correlation of quantitation with major bcr abl mrna kits
International Journal of Hematology, 2015Co-Authors: Hirohisa Nakamae, Chikashi Yoshida, Yasuhiko Miyata, Michihiro Hidaka, Naokuni Uike, Daisuke Koga, Takayuki Sogabe, Itaru Matsumura, Yuzuru Kanakura, Tomoki NaoeAbstract:The current first-line therapy of chronic myeloid leukemia (CML) is based on tyrosine kinase inhibitors. Diagnostic kits that are capable of identifying at least a 4.5 log reduction in the international scale % BCR-ABL/ABL (IS % BCR-ABL/ABL) are needed for use in the clinical evaluation of deeper molecular response to treatment and to determine the timing of dose selection or treatment interruption during the course of treatment. In this study, we evaluated the performance of a new diagnostic kit, ODK-1201, designed to be capable of performing reverse transcription and quantitative PCR in a single tube for the quantitation of major BCR-ABL mRNA. The kit demonstrated excellent assay performance (limit of detection 0.0007 %) and a broader detection range of BCR-ABL mRNA in peripheral blood compared to a commercially available kit for CML (Amp-CML). ODK-1201 was also shown to be as sensitive as Ipsogen and Molecular MD kits in the same assay. Results obtained in this study indicate evidences that ODK-1201 was capable of identifying at least a 4.5 log reduction in the IS % BCR-ABL/ABL.
Cheryl C.h. Yang - One of the best experts on this subject based on the ideXlab platform.
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Functional characterization of caudal hypoglossal neurons by spectral patterns of neuronal discharges in the rat.
Neuroscience, 1997Co-Authors: Cheryl C.h. Yang, Terry B.j. Kuo, Samuel H.h. ChanAbstract:This study evaluated the spectral characteristics of neuronal discharges in the caudal hypoglossal nucleus and their physiological relevance in adult, male Sprague Dawley rats which were anaesthetized and maintained with pentobarbital sodium. Based on auto-spectral analysis of extracellular single-neuron activity, three spectral patterns were identified in the spontaneous discharges of hypoglossal neurons. Neurons that exhibited a rhythmic pattern manifested a concentrated peak in the auto-spectrogram that corresponded to the mean discharge rate. A majority of hypoglossal neurons displayed the modulated pattern, which was manifested either as scattered power densities (wide-band modulated pattern) or with a peak frequency component that was different from the mean discharge rate (narrow-band modulated pattern). Neurons that exhibited a mixed pattern displayed both rhythmic and modulated spectral patterns. Cross-spectral analysis further revealed that respiratory modulation constituted a major physiological influence on caudal hypoglossal neurons. The respiratory modulated pattern, however, could be converted to a mixed pattern in the presence of a central Dipsogen, angiotensin III. The results suggest that the spectral patterns of neuronal discharges in caudal hypoglossal neurons represent manifestations of multiple physiological information, including that regarding respiration and Dipsogenesis, which is encoded in these neurons. It was also shown that this information may only be revealed by auto-spectral and cross-spectral analysis of neuronal discharge signals.
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Central effect of angiotensin III on caudal hypoglossal neurons in rats
American Journal of Physiology-Regulatory Integrative and Comparative Physiology, 1995Co-Authors: Cheryl C.h. Yang, Julie Y.h. Chan, Samuel H.h. ChanAbstract:We communicated the central effect of angiotensin III (ANG III), a potent signal for extracellular dehydration, on single neurons in the caudal hypoglossal nucleus of Sprague-Dawley rats anesthetized with pentobarbital sodium. A significant number (121 of 168) of caudal hypoglossal neurons responded to intracerebroventricular application of ANG III (80 or 160 pmol), with either an increase (n = 83) or decrease (n = 38) in their spontaneous discharge. These effects of ANG III were significantly reversed by intracerebroventricular application of the nonpeptide angiotensin AT1 receptor antagonist losartan (40 nmol), but not by the AT2 antagonist, PD-123319. The hypoglossal neuronal responses to repeated administration of ANG III (80 pmol), delivered at an interval < or = 18 min, exhibited acute tachyphylaxis. Intracerebroventricular administration of the cholinergic Dipsogen, carbachol (50 ng), or the osmotic stimulant, hypertonic saline (0.5 M), also elicited responses in ANG III-responsive hypoglossal neurons. These results suggest that neurons in the caudal hypoglossal nucleus may serve as the final common pathway for extracellular and, possibly, intracellular thirst in the rat. Furthermore, it is likely that the action of ANG III is mediated by the AT1 subtype of angiotensin receptors.