The effect of age, castration and androgen-replacement therapy upon the stimulatory activity of the beta-adrenergic agonist isoproterenol on cyclic AMP accumulation was determined in rat prostatic epithelial cells. The potency of isoproterenol was similar in all the experimental models (ED50 = 0.3-0.4 microM). Mature animals showed a lower efficiency of isoproterenol than that of pubertal rats. Pubertal rats (which are absolutely dependent on androgens) exhibited an increase of the responsiveness of prostatic cyclic AMP to isoproterenol after castration, normalization being reached after subsequent testosterone treatment; this feature could be reproduced by in vitro incubation of the corresponding cells with testosterone or dihydrotestosterone. Mature rats (which are relatively dependent on androgens) maintained the efficiency of isoproterenol upon prostatic cyclic AMP after castration, and testosterone therapy elicited an increase of this activity. The present study contributes original observations mainly in the puberty period and supports the importance of the androgenic status not only for direct actions of androgens but also for the regulation of many other hormone/neurotransmitter/growth factor receptor-effector systems.