Involvement of serotonin receptors in methionine sulfoximine-induced hypothermia in the rat.
L-Methionine-D,L-sulfoximine (MSO), intraperitoneally (i.p.) or intracerebroventricularly (i.c.v.) (third ventricle) injected at a convulsant dose, induced a centrally mediated body hypothermia in the restrained rat maintained at an ambient temperature of 23 degrees C. Pretreatment with (+/-)-pindolol (1.5-3 mg/kg s.c.) significantly attenuated MSO-induced hypothermia, but at a dose of 6 mg/kg s.c. hypothermia developed without any modification of its characteristics. Pretreatment with (-)-propranolol (16-25 mg/kg i.p.) potentiated MSO-induced hypothermia, but pretreatment of MSO-treated rats with ketanserin (0.7-4 mg/kg i.p.) did not significantly modify hypothermia. Selective antagonists for beta-adrenoceptors were used and their effects on MSO-induced hypothermia were compared with those of pindolol and propranolol. Pretreatment with betaxolol (1.5-4 mg/kg s.c.) did not modify the hypothermia following administration of MSO, but potentiation of hypothermia was recorded in rats pretreated with ICI 118,551 (2.26 mg/kg i.p.) then i.p. injected with MSO. These findings favour a control exerted by 5-HT1 receptors in the central development of MSO-induced hypothermia in the restrained rat.
Laboratoire de Physiologie générale, Faculté des Sciences, Université de Nancy 1, France.
M
M
Ginefri-Gayet
J
J
Gayet
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D015784:Betaxolol / Q000494:pharmacology; D001831:Body Temperature / Q000187:drug effects / Q000502:physiology; D002490:Central Nervous System / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D004305:Dose-Response Relationship, Drug; D007036:Hypothermia, Induced; D007650:Ketanserin / Q000494:pharmacology; D008297:Male; D008717:Methionine Sulfoximine / Q000494:pharmacology*; D010869:Pindolol / Q000494:pharmacology; D011412:Propanolamines / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D011985:Receptors, Serotonin / Q000187:drug effects / Q000502:physiology*
D000319:Adrenergic beta-Antagonists; D011412:Propanolamines; D011985:Receptors, Serotonin; D008717:Methionine Sulfoximine; C026777:ICI 118551; D007650:Ketanserin; D011433:Propranolol; D010869:Pindolol; D015784:Betaxolol