Open AccessRisperidone and 5-HT2A Receptor Antagonists Attenuate and Reverse Cocaine-Induced Hyperthermia in Rats
Author(s) -
Tsuyoshi Okada,
Katsutoshi Shioda,
Akiko Makiguchi,
Shiro Suda
Publication year - 2020
Publication title -
international journal of neuropsychopharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.897
H-Index - 107
eISSN - 1469-5111
pISSN - 1461-1457
DOI - 10.1093/ijnp/pyaa065
Subject(s) - ketanserin , ritanserin , pharmacology , risperidone , hyperthermia , sulpiride , haloperidol , medicine , dopamine antagonist , microdialysis , dopamine , serotonin , anesthesia , 5 ht receptor , antagonist , receptor , endocrinology , schizophrenia (object oriented programming) , psychiatry
Background Cocaine (benzoylmethylecgonine) is one of the most widely used illegal psychostimulant drugs worldwide, and mortality from acute intoxication is increasing. Suppressing hyperthermia is effective in reducing cocaine-related mortality, but a definitive therapy has not yet been found. In this study, we assessed the ability of risperidone to attenuate acute cocaine-induced hyperthermia and delineated the mechanism of its action. Methods Rats were injected i.p. with saline, risperidone, ketanserin, ritanserin, haloperidol, or SCH 23 390 before and after injection of cocaine (30 mg/kg) or with WAY-00 635, SB 206 553, or sulpiride before cocaine injection; thereafter, the rectal temperature was measured every 30 minutes for up to 4 hours. In vivo microdialysis was used to reveal the effect of risperidone on cocaine-induced elevation of dopamine (DA), serotonin (5-HT), and noradrenaline concentrations in the anterior hypothalamus. For post-administration experiments, saline or risperidone (0.5 mg/kg) were injected into rats, and cocaine (30 mg/kg) was injected 15 minutes later. For every 30 minutes thereafter, DA, 5-HT, and noradrenaline levels were measured for up to 240 minutes after cocaine administration. Results Risperidone, 5-HT2A receptor antagonists, and D1 receptor antagonistic drugs prevented and reversed cocaine-induced hyperthermia. In contrast, receptor antagonists for 5-HT1A, 5-HT2B/2C, and D2 did not alter cocaine-induced hyperthermia. Risperidone treatment further attenuated cocaine-induced elevation of DA. Conclusions Our results indicate that risperidone attenuates cocaine-induced hyperthermia primarily by blocking the activities of the 5-HT2A and D1 receptors and may be potentially useful for treating cocaine-induced acute hyperthermia in humans.