The pharmacology of the behavioural and hypothermic responses of rats to 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT).
The hypothermic and motor behavioural responses to 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) have been investigated in the rat. The dose-effect relationship showed that hypothermia appeared at a lower dose than a definite motor syndrome. The hypothermic response to 8-OH-DPAT was attenuated following depletion of 5-hydroxytryptamine (5-HT) by repeated intraperitoneal (IP) administration of parachlorophenylalanine (200 mg/kg) or by injection of 5,7-dihydroxytryptamine (5,7-DHT, 100 micrograms) into the region of the third ventricle; the motor behavioural response produced simultaneously was not. Indeed, after 5,7-DHT, it was increased. Quipazine (1 mg/kg, IP) antagonised the hypothermic response and facilitated the motor behaviour. Clenbuterol (2.5 mg/kg, IP) increased both hypothermic and motor responses. (+/-)-propranolol was without effect on the simple hypermotility produced by 8-OH-DPAT, although it is known to antagonise the hypothermic and stereotyped motor responses. It is concluded that 8-OH-DPAT probably produces its hypothermic effects by actions at 5-HT receptors located presynaptically on 5-HT neurones, while the stereotyped components of the serotonin syndrome appear to be mediated by post-synaptic receptors.
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D001831:Body Temperature / Q000187:drug effects*; D001923:Brain Chemistry / Q000187:drug effects; D002976:Clenbuterol / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D008297:Male; D009281:Naphthalenes / Q000494:pharmacology*; D009498:Neurotoxins / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D011814:Quipazine / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013764:Tetrahydronaphthalenes / Q000494:pharmacology*
D009281:Naphthalenes; D009498:Neurotoxins; D013764:Tetrahydronaphthalenes; D011814:Quipazine; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D011433:Propranolol; D002976:Clenbuterol