Adrenergic and cholinergic muscarinic receptors in the prostate of young and old rabbits.

We measured the autonomic receptors in prostate homogenates of young (6 months) and old (4.5-5 years) rabbits in order to study the effect of age on the prostatic autonomic receptors using radioligand binding techniques. Saturation studies with 3H-prazosine, 3H-yohimbine, 3H-dihydroalprenolol and 3H-quinuclidinyl benzilate demonstrated a significant amount of alpha 1-, alpha 2-, beta-adrenergic and muscarinic cholinergic receptors in prostatic tissues of both young and old rabbits. There were more alpha 1- and alpha 2-receptors in the prostate of old rabbits, although these differences were not statistically significant. There was no difference in the amount of beta-adrenergic and muscarinic receptors in the prostates of young and old rabbits. But there was a difference in the distribution of these autonomic receptors in the prostates of young and old rabbits. These results suggest that aging may affect the distribution of autonomic receptors, but not significantly the amount of autonomic receptors in the rabbit prostate.