VENTRAL PROSTATE STRUCTURE AND SERUM TESTOSTERONE LEVELS AFTER CHRONIC TREATMENT WITH ISOPROTERENOL IN ADULT RATS WITH DIFFERENT ANDROGEN STATUS

The effects of chronic administration of the beta-adrenergic agonist i soproterenol (ISO) (120 mu g/kg per day; subcutaneously) on the ventra l prostate structure and serum testosterone concentrations were examin ed in adult rats with different androgen status: intact, intact testos terone-injected (1 mg/rat), surgically and chemically castrated rats. Chemical castration was evoked by an intraperitoneal injection of etha ne dimethanesulfonate (EDS) (75 mg/kg). A ventral prostate response wa s only observed in intact and chemically castrated animals. Stereologi cal analysis revealed atrophic changes in the glandular compartment of the prostate of ISO-treated intact rats, but they were probably the c onsequence of significantly decreased serum testosterone levels. In ad dition, in these animals alterations were found in the morphometrical parameters of the ventral prostate blood vessels, their relative and t otal volumes being increased. In chemically castrated rats, administra tion of ISO from the day of EDS application partially prevented the po stcastrational regression of the ventral prostate without affecting bl ood testosterone level. However, it seems that the discharge of glandu lar secretion was attenuated at the same time. These results show that chronic treatment with ISO may have both stimulatory and inhibitory e ffects on the rat ventral prostate depending on the androgen status of the animals and, accordingly, on the site of ISO-action.