The effects of sexual maturation on alpha-adrenoceptors in female rabbits.

alpha-Adrenoceptor number and function were examined in brain, platelets, and other peripheral tissues of young (2-3 months) and mature (6-8 months) non pregnant female rabbits. alpha1-Adrenoceptor number was significantly higher in forebrain, hindbrain, spleen and heart of mature rabbits. alpha2-Adrenoceptor number, on the other hand, was found to be significantly lower in platelets, forebrain and spleen but not changed in hindbrain and kidney of mature animals compared to young females. There was a significant reduction in platelet aggregation with maturation. However, no change in in vivo pressor or depressor responses to alpha-adrenoceptor agonists was observed in vivo.