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Mohammad-reza Zarrindast - One of the best experts on this subject based on the ideXlab platform.
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Effect of dextromethorphan on antinociception and tolerance induced by swim-stress in the Formalin Test.
Archives of Iranian medicine, 2008Co-Authors: Soheila Fazli-tabaei, Amir Maghsoudi, Avid Bazaz, Navid Bazaz, Azadeh Modirzadeh, Mohammad-reza ZarrindastAbstract:Background: In the present study, the effect of dextromethorphan on antinociception and tolerance induced by water swim-stress in the Formalin Test was investigated. Methods: Swim- stress at 8oC induces antinociception in both phases of the Formalin Test. Intraperitoneal administration of dextromethorphan (60 mg/kg) also induces antinociception in the second phase of the Formalin Test. The lower doses of dextromethorphan (1.25, 2.5, and 5 mg/kg) which did not induce antinociception alone, but did so in combination with swim- stress (40 second), showed antinociceptive effect in both phases of the Test. Exposure to water swimming stress with a period of 20 sec, once daily for three days, altered swim- stress- induced antinociception in the Formalin Test, when Tested on the fourth day. Results: In these animals, exposure to either water swimming stress alone or water swimming stress in combination with dextromethorphan showed potentiation of antinociception induced by swim- stress up to 20 second and decreased the response induced by 40 and 60 second swimstress, indicating a tolerance induction. Dextromethorphan (20 mg/kg) did not alter the changes induced by three days exposure to swim- stress. Conclusion: The results may indicate a possible involvement of n-methyl-d-aspartate receptor mechanism in the antinociception but not tolerance induced by swim- stress at 8oC.
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ON THE MECHANISM OF CARBAMAZEPIN-INDUCED ANTINOCICEPTION IN THE Formalin Test
The International journal of neuroscience, 2006Co-Authors: Mousa Sahebgharani, Ahmad Abdi Hossein-abad, Mohammad-reza ZarrindastAbstract:In the present study, the effect of lidocaine (a sodium channel blocker) on carbamazepine-induced antinociception, in Formalin Test was investigated. Intraperitoneal (i.p.) administration of different doses of carbamazepine (3.5, 7, 15, and 30 mg/kg) induced a dose-dependent antinociception in mice, in the first and second phases of the Test. Different doses of lidocaine as a sodium channel blocker (5, 10, and 20 mg/kg, i.p.) also induced antinociception in both phases of the Formalin Test. It is noted that lidocaine could potentiate the response of carbamazepine in the first, but not in the second, phase of the Formalin Test. Meanwhile i.p. administration of different doses of Prazosin, α1 adrenoceptor antagonist (0.125, 0.25, and 0.5 mg/kg), Yohimbine, α2 adrenoceptor antagonist (0.25, 0.5, and 1 mg/kg), Bicuculline, GABAA receptor antagonist (1.5 and 3 mg/kg), and CGP 35348, GABAB receptor antagonist (100 and 200 mg/kg) exert dose-dependent antinociceptive effect in both phases of the Formalin Test. It...
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Dopamine receptor mechanism(s) and antinociception and tolerance induced by swim stress in Formalin Test.
Behavioural pharmacology, 2006Co-Authors: Soheila Fazli-tabaei, Seyed Hossein Yahyavi, Maryam Nouri, Hamed Zartab, Golrokh Javid, Sanam Loghavi, Mohammad-reza ZarrindastAbstract:In the present study, involvement of D1 and D2 dopamine receptors in the antinociception and tolerance induced by water swim stress in the Formalin Test has been investigated. Water swim stress at 20 degrees C temperature induced antinociception in both phases of the Formalin Test. Intraperitoneal administration of the D2 dopamine receptor antagonist, sulpiride (25 and 50 mg/kg) reduced swim stress-induced antinociception in the second phase of the Formalin Test. A higher dose of the D1 dopamine receptor antagonist, SCH23390 (0.1 mg/kg, intraperitoneal) also reduced swim stress-induced antinociception in both phases of the Test. Exposure to 3 min water swimming stress, once daily for 3 days, induced tolerance to swim stress-induced antinociception in the second phase of the Formalin Test. Administration of sulpiride (12.5, 25 and 50 mg/kg), during exposure to water swimming stress (once daily for 3 days), decreased tolerance in the second phase, whereas the antagonist (12.5 and 50 mg/kg) increased pain scores in the first phase of the Formalin Test. Sulpiride (25 mg/kg) treatment however, once daily for 3 days with no water swimming stress, did not alter swim stress-induced antinociception (0.5, 1 and 3 min Tests). Similarly, repeated treatment with SCH23390 (0.05 mg/kg) and water swimming stress did not alter tolerance induced by water swimming stress. Repeated administration of the antagonist in the absence of water swimming stress also did not change swim stress-induced antinociception. The results may indicate a possible involvement of both dopamine D1 and D2 receptors in the antinociception induced by swim stress and D2 receptor mechanism in the tolerance induced by repeated swim stress.
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DIFFERENTIAL ANTINOCICEPTIVE EFFECTS OF YOHIMBINE IN THE RAT Formalin Test
DARU, 2005Co-Authors: Mohammad Javad Khodayar, Mohammad-reza Zarrindast, Nima Naderi, Bijan ShafaghiAbstract:Although many pharmacological studies indicate that yohimbine antagonize the antinociceptive effects of α2-adrenoceptor agonists, there are evidences that yohimbine by itself produces antinociceptive effects in the Formalin Test. However, its site of action on nociceptive processing is not fully understood. In this investigation, a series of experiments were designed to study the antinociceptive effects of intraperitoneal (i.p.), intraplantar (i.pl.) and intrathecal (i.t.) administration of yohimbine in the nociceptive processing.Yohimbine (2 and 4 mg/kg, i.p.) induced antinociception in the early phase (0-5 min) as well as in the late phase (10-60 min) of Formalin Test. While i.pl. yohimbine (5-100 µg) decreased the response in the early phase, i.t. yohimbine (30 µg) decreased pain behavior in the late phase of Formalin Test in rats. In conclusion, our findings show that yohimbine induces antinociception in both phases of Formalin Test and its effects are produced at least in part through actions at the peripheral terminal of primary afferents or at the spinal level.
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Adenosine receptor mediates nicotine-induced antinociception in Formalin Test.
Pharmacological research, 2005Co-Authors: Homayoun Homayounfar, Mousa Sahebgharani, Nida Jamali-raeufy, Mohammad-reza ZarrindastAbstract:Abstract In this study, the effect of adenosine receptor agents on nicotine induced antinociception, in Formalin Test, has been investigated. Intraperitoneal (i.p.) administration of different doses of nicotine (0.1, 1, 10 and 100 μg kg −1 ) induced a dose-dependent antinociception in mice, in the both first and second phases of the Test. Adenosine receptor antagonist, theophylline (5, 10, 20 and 80 mg kg −1 , i.p.) also induced antinociception in the both phases, while a dose of the drug (40 mg kg −1 , i.p.) did not induce any response. Theophylline reduced antinociception induced by nicotine in both phases of Formalin Test. The A 2 receptor agonist, 5′- N -ethylcarboxamide adenosine (NECA; 1 and 5 μg kg −1 , i.p.) also produced antinociception, which was reversed with different doses of theophylline (5, 10, 20 and 40 mg kg −1 , i.p.). But administration of the adenosine receptor agonist, NECA did not potentiate the response of nicotine. It is concluded that adenosine system may be involved in modulation of antinociception induced by nicotine.
Yaghoub Fathollahi - One of the best experts on this subject based on the ideXlab platform.
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orexin a microinjection into the rostral ventromedial medulla causes antinociception on Formalin Test
Pharmacology Biochemistry and Behavior, 2014Co-Authors: Hassan Azhdarizarmehri, Saeed Semnanian, Yaghoub FathollahiAbstract:Abstract Orexins are produced from neurons which are restricted to a few regions of the lateral hypothalamus (LH), where they are important in pain modulation. The orexin receptors and orexinergic projections are localized in regions previously shown to play a role in pain modulation such as rostral ventromedial medulla (RVM). The effect of orexin-A (ORXA) microinjection into the RVM on nociceptive behaviors was examined using the Formalin Test. Microinjection of ORXA into the RVM, but not adjacent reticularis gigantocellularis (Gi) nucleus, decreased Formalin induced nociceptive behaviors. Pretreatment with a selective OX1R antagonist, SB-334867 inhibited the antinociception produced by ORXA, while the administration of SB-334867 alone had no effect. These data demonstrate that ORXA-induced antinociception in the Formalin Test is mediated in part through orexin1 receptors in the RVM.
Hassan Azhdarizarmehri - One of the best experts on this subject based on the ideXlab platform.
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orexin a microinjection into the rostral ventromedial medulla causes antinociception on Formalin Test
Pharmacology Biochemistry and Behavior, 2014Co-Authors: Hassan Azhdarizarmehri, Saeed Semnanian, Yaghoub FathollahiAbstract:Abstract Orexins are produced from neurons which are restricted to a few regions of the lateral hypothalamus (LH), where they are important in pain modulation. The orexin receptors and orexinergic projections are localized in regions previously shown to play a role in pain modulation such as rostral ventromedial medulla (RVM). The effect of orexin-A (ORXA) microinjection into the RVM on nociceptive behaviors was examined using the Formalin Test. Microinjection of ORXA into the RVM, but not adjacent reticularis gigantocellularis (Gi) nucleus, decreased Formalin induced nociceptive behaviors. Pretreatment with a selective OX1R antagonist, SB-334867 inhibited the antinociception produced by ORXA, while the administration of SB-334867 alone had no effect. These data demonstrate that ORXA-induced antinociception in the Formalin Test is mediated in part through orexin1 receptors in the RVM.
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orexin receptor type 1 antagonist sb 334867 decreases morphine induced antinociceptive effect in Formalin Test
Pharmacology Biochemistry and Behavior, 2013Co-Authors: Hassan Azhdarizarmehri, Mohammadhossein Esmaeili, Mohammad Sofiabadi, Hashem HaghdoostyazdiAbstract:Abstract Orexin-A and orexin-B are two neuropeptides selectively synthesized in the lateral hypothalamus (LH), a region involved in morphine induced analgesia and pain modulation. Furthermore, orexin-A has been reported to produce an analgesic effect in pain models, which was blocked by orexin-1 receptor antagonist SB-334867, but not naloxone. We studied the effects of intracerebroventricular (ICV) injection of SB-334867, a selective orexin receptor type-1 antagonist, on morphine-induced antinociceptive effect in Formalin Test in rats. Morphine injection at a dose of 1.5 mg/kg caused a significant decrease in the Formalin-induced nociceptive behaviors in phase 1, interphase, and phase 2A, whereas at doses of 3, 6, and 10 mg/kg, a significant reduction in the Formalin-induced nociceptive behaviors was observed in all phases. The ICV injection of SB-334867 alone had no effect on the Formalin-induced nociceptive behaviors. Pre-treatment with SB-334867 at a dose of 0.5 nmol significantly attenuated the analgesia induced by morphine (at dose 1.5 mg/kg of morphine; interphase and phase 2B and at dose 3 mg/kg of morphine just phase 2B of Formalin Test). Also, pre-treatment with SB-334867 at a dose of 5 nmol considerably attenuated the morphine-induced analgesia (at dose 1.5 mg/kg of morphine; phase 1, interphase, and phase 2, at dose 3 and 6 mg/kg of morphine just phase 2 of Formalin Test). Pre-treatment with SB-334867 at a dose of 50 nmol remarkably attenuated the morphine-induced analgesia (at dose 1.5 and 3 mg/kg of morphine; in phase 1, interphase, and phase 2 and also at dose 6 mg/kg of morphine; phase 1 and phase 2B of Formalin Test). These data suggest that the antinociceptive effects of morphine in Formalin Test might be associated with orexin receptor type-1. Our findings reveal a new role for the lateral hypothalamus orexin neurons in the morphine-induced analgesia.
Patrick Raboisson - One of the best experts on this subject based on the ideXlab platform.
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The orofacial Formalin Test.
Neuroscience and biobehavioral reviews, 2004Co-Authors: Patrick Raboisson, Radhouane DallelAbstract:The subcutaneous injection of Formalin into the rat upper lip generates behavioral responses that last several minutes. The time course of the response is similar to what is observed following Formalin injection into the paw, i.e. biphasic, with an early and short-lasting first phase followed, after a quiescent period by a second, prolonged (tonic) phase. The applied chemical stimulus (Formalin) can be qualified as noxious since it produces tissue injury, activates Adelta and C nociceptors as well as trigeminal and spinal nociceptive neurons and is felt as painful in man. In addition, increasing the concentration of Formalin causes a parallel aggravation of histological signs of tissue inflammation and injury. The measured behavioral response (face rubbing) is a relevant end-point: prolonged face rubbing is evoked by Formalin but not saline injection and a positive relationship between the amplitude of the response and the Formalin concentration is observed, at least up to 2.5%. At higher Formalin concentrations, the use of other or additional end-points should be considered. Finally, the behavioral response in the orofacial Formalin Test is sensitive to various opioid and non-opioid analgesics. The orofacial Formalin Test can then be considered as a reliable way of producing and quantifying nociception in the trigeminal region of the rat.
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The orofacial Formalin Test in rats : effects of different Formalin concentrations
Pain, 1995Co-Authors: Pierre Clavelou, Radhouane Dallel, Thierry Orliaguet, Alain Woda, Patrick RaboissonAbstract:In this study of the orofacial Formalin Test in rats, the effects of different Formalin concentrations (0.2%, 0.5%, 1.5%, 2.5%, 5% and 10%) on the behavioural nociceptive response (face rubbing) was investigated. The histological responses of the skin were also evaluated. Increasing the concentration of Formalin caused a parallel aggravation of histological signs of tissue inflammation and injury. All concentrations provoked an early phase of nociceptive response, but its intensity was not concentration-dependent. The 2nd phase of response to Formalin only occurred for concentrations of 1.5% and higher. A positive relationship between the Formalin concentration and the amplitude of the rubbing activity measured between 12 and 45 min after injection could be observed until 2.5% but with the highest concentrations (5 and 10%), the amplitude of the response decreased. Our findings indicate that the orofacial Formalin Test should be carried out using concentration between 0.5 and 2.5%. This is essential to assess increase as well as decrease in pain intensity. Moreover, this will have the effect of minimizing the suffering of the experimental animal.
Vinicio Granados-soto - One of the best experts on this subject based on the ideXlab platform.
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Synergistic antinociceptive interaction between acetaminophen or metamizol and B vitamins in the Formalin Test
Drug Development Research, 2005Co-Authors: Flavio Terán-rosales, Roberto Medina-santillán, Gerardo Reyes-garcía, Vinicio Granados-sotoAbstract:There is evidence that B vitamins produce antinociception in animals. However, potentiation of NSAID-induced antinociception by B vitamins is unclear. The current study was designed to investigate the antinociceptive interaction between a mixture of B vitamins and either acetaminophen or metamizol. Acetaminophen (56-316 mg/kg), metamizol (32-178 mg/kg), and the mixture of B vitamins (32-178 mg/kg of thiamine, pyridoxine, and cyanocobalamin in a 100:100:1 proportion, respectively) or a combination of each drug with the B vitamins mixture was administered orally to female Wistar rats, and the antinociceptive effect determined in the Formalin Test. Isobolographic analyses were used to define the nature of the interaction between NSAIDs and B vitamins. Oral administration of either drug produced a dose-related antinociceptive effect. Isobolographic analyses revealed that both acetaminophen or metamizol and the B vitamins mixture interacted synergistically in the Formalin Test, suggesting that these two combinations could be useful in treating inflammatory pain states. Drug Dev. Res. 66:286-294, 2006. � c 2006 Wiley-Liss, Inc.
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Pinacidil increases diclofenac antinociception in the Formalin Test.
Proceedings of the Western Pharmacology Society, 2005Co-Authors: Gilberto Castañeda-hernández, Vinicio Granados-soto, Mario I. OrtizAbstract:Evidence suggests that the ATP-sensitive K+ channels are important in the peripheral antinociceptive effect of diclofenac. Combinations of nonsteroidal anti-inflammatory drugs (NSAIDs) with other different drugs are currently used in clinical practice to increase the analgesic efficacy and to reduce adverse events. We evaluated the effect of the combination of diclofenac and the activator of K+ channels pinacidil in the Formalin Test. Female Wistar rats (180-200 g) were injected in the dorsal surface of the right hind paw with 50 microl of Formalin (1%). Nociception was quantified as the number of flinches of the injected paw during the next 60 mins, while reduction of flinches was considered antinociception. Ipsilateral, but not contralateral, pretreatment with diclofenac (25-200 microg/paw) or pinacidil (5-50 microg/paw) significantly reduced, in a dose-dependent manner the Formalin-induced flinching behavior during the second phase of the Test. To determine if pinacidil was able to increase the effect of diclofenac, noneffective increasing doses of pinacidil were coadministered with an ineffective dose of diclofenac (25 microg). The local co-administration of pinacidil and diclofenac produced a significant reduction in the number of flinches during phase 2, but not during phase 1 of the Test compared to the effect of either drug alone. In conclusion, the combination of individually ineffective doses of diclofenac and pinacidil produce an antinociceptive effect in the Formalin Test. In addition, pinacidil increased the action of diclofenac, probably through the activation of K+ channels.
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Pharmacological evidence for the activation of Ca2+-activated K+ channels by meloxicam in the Formalin Test.
Pharmacology biochemistry and behavior, 2005Co-Authors: Mario I. Ortiz, Gilberto Castañeda-hernández, Vinicio Granados-sotoAbstract:The possible participation of K+ channels in the antinociceptive action of meloxicam was assessed in the 1% Formalin Test. Local peripheral administration of meloxicam produced a dose-dependent antinociception only during the second phase of the Formalin Test. K+ channel blockers alone did not modify Formalin-induced nociceptive behavior. However, local peripheral pretreatment of the paw with charybdotoxin and apamin (large- and small-conductance Ca2+-activated K+ channel inhibitors, respectively), 4-aminopyridine and tetraethylammonium (non-selective voltage-dependent K+ channel inhibitors), but not glibenclamide or tolbutamide (ATP-sensitive K+ channel inhibitors), dose-dependently prevented meloxicam-induced antinociception. It is concluded that meloxicam could open large- and small-conductance Ca2+-activated K+ channels, but not ATP-sensitive K+ channels, in order to produce its peripheral antinociceptive effect in the Formalin Test. The participation of voltage-dependent K+ channels was also suggested, but since non-selective inhibitors were used the data await further confirmation.
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Sildenafil increases diclofenac antinociception in the Formalin Test.
European journal of pharmacology, 2001Co-Authors: Raquel Asomoza-espinosa, Rosario Alonso-lópez, Teresa Mixcoatl-zecuatl, Patricia Aguirre-bañuelos, Jorge E Torres-lópez, Vinicio Granados-sotoAbstract:The antinociceptive activity of an inhibitor of phosphodiesterase 5, alone or combined with diclofenac, was assessed in the Formalin Test. Local administration of diclofenac produced a significant antinociception in both phases of the Formalin Test in female Wistar rats. In contrast, 1-[4-ethoxy-3-(6,7-dihydro-1-methyl-7-oxo-3-propyl-1H-pyrazolo [3,4-d]pyrimidin-5-yl)phenylsulfonyl]-4-methyl piperazine (sildenafil, an inhibitor of phosphodiesterase 5) produced significant antinociception, only during the second phase of the Formalin Test. Non-effective doses of sildenafil (25-100 microg/paw) significantly increased the antinociceptive effect of an inactive dose of diclofenac (25 microg) in both phases of the Test. The antinociception produced by the drugs alone or the combination was due to a local action, as its administration in the contralateral paw was ineffective. Since sildenafil is a potent and selective inhibitor of phosphodiesterase 5, our results suggest that this drug produced its antinociceptive activity, and increased that of diclofenac, probably through the inhibition of cyclic GMP degradation.