Effect of reserpine on behavioural responses to agonists at 5-HT1A, 5-HT1B, 5-HT2A, and 5-HT2C receptor subtypes.
Rats were given a single dose of reserpine (5 mg/kg s.c.) and behavioural responses to agonists at 5-HT receptor subtypes compared with those of control animals 21 days later. The following effects of activating postsynaptic 5-HT1A receptors by the agonist 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT) were significantly increased: tail-flick, reciprocal forepaw treading, flat body posture. The hyperphagic effect of activating presynaptic 5-HT1A receptors by 8-OH-DPAT tended to increase and hypothermia on activating postsynaptic 5-HT1A sites tended to decrease. The hyperlocomotor effect of activating 5-HT1A sites also tended to decrease possibly as a result of a dependence of this response on the known depletion of catecholamines by reserpine. Head shakes on activating 5-HT2A receptors by 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) and two effects of activating 5-HT2C receptors by 1-(3-chlorophenyl) piperazine (mCPP) were significantly increased (hypophagia, anxiety) and a third effect, hypolocomotion tended to increase but hypophagia on activating postsynaptic 5-HT1B receptors by CP-94, 253 was significantly attenuated. The results are discussed with particular reference to altered 5-HT function in depression.
Heslop
K E
KE
Department of Neurochemistry, Institute of Neurology, London, UK.
Curzon
G
G
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000662:Amphetamines / Q000494:pharmacology; D000818:Animals; D001007:Anxiety / Q000188:drug therapy; D001522:Behavior, Animal / Q000187:drug effects*; D001833:Body Temperature Regulation / Q000187:drug effects; D005247:Feeding Behavior / Q000187:drug effects; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D010147:Pain Measurement; D010879:Piperazines / Q000494:pharmacology; D011187:Posture; D051381:Rats; D017207:Rats, Sprague-Dawley; D012110:Reserpine / Q000494:pharmacology*; D017366:Serotonin Receptor Agonists / Q000494:pharmacology*
D000662:Amphetamines; D010879:Piperazines; D017366:Serotonin Receptor Agonists; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D012110:Reserpine; C015952:4-iodo-2,5-dimethoxyphenylisopropylamine; C015068:1-(3-chlorophenyl)piperazine