[An analysis of the hypothermic action of 8-hydroxy-2-(di-N-propylamino)tetralin, 1-(2-pyrimidinyl)piperazine and its derivatives].

The hypothermic activity of 8-OH-DRAT, 1-(2-pyrimidinyl) piperazine (1-PP), buspirone and its structure analogues tightly correlates with the degree of inhibition of 3H-serotonine release by electrically stimulated dorsal raphe slices (r = 0.84), but not cerebral cortex slices (r = 0.66). The pretreatment of mice with p-chlorphenylalanine decreased the hypothermic effects evoked by 8-OH-DRAT, buspirone, campirone (but not 1-PP) only in first 30 min after there injection. It was concluded that hypothermic effects of 8-OH-DRAT, buspirone and its structure analogues were bound with preferable influence as partial agonists on the postsynaptic serotonine 1A receptors. Ipsapirone as a partial agonist has maximal antagonistic activity.