title: The beta 2-adrenoceptor agonists clenbuterol and salbutamol enhance the hypothermic action of 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) in mice by a central mechanism.
abstract: The hypothermic response of mice to injection of 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) was enhanced by injection of the beta 2-adrenoceptor agonist clenbuterol with an ED50 of 0.4 mg/kg. This effect of clenbuterol is through a central mechanism since salbutamol, a beta 2-adrenoceptor agonist with poor penetration into the brain, had no effect at a dose of 2 mg/kg, whereas intracerebroventricular injection of clenbuterol (3 micrograms) or salbutamol (2 micrograms), produced a significant enhancement. The enhancing effect of clenbuterol was unaffected by pretreatment with the beta 1-adrenoceptor antagonist metoprolol but was totally antagonised by the beta 2-adrenoceptor antagonist ICI 118,551 and to a lesser extent by butoxamine. Clenbuterol therefore enhances the function of the presynaptic 5-HT1 receptor through a beta 2-adrenoceptor mechanism.
mesh_terms: D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000420:Albuterol / Q000008:administration & dosage*; D000818:Animals; D001831:Body Temperature / Q000187:drug effects*; D001921:Brain / Q000187:drug effects*; D002976:Clenbuterol / Q000008:administration & dosage*; D004357:Drug Synergism; D004983:Ethanolamines / Q000008:administration & dosage*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009281:Naphthalenes / Q000008:administration & dosage*; D013268:Stimulation, Chemical; D013764:Tetrahydronaphthalenes / Q000008:administration & dosage*
chemical_list: D004983:Ethanolamines; D009281:Naphthalenes; D013764:Tetrahydronaphthalenes; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000420:Albuterol; D002976:Clenbuterol