PREPUBERTAL DEVELOPMENT OF RAT PROSTATE AND SEMINAL-VESICLE FOLLOWINGCHEMICAL SYMPATHECTOMY WITH GUANETHIDINE

1. The internal genital organs of prepubertal, 21-day old male Wistar rats were sympathectomized by ip injection of guanethidine (G), at dos es of 5 mg/kg per day (N = 10) or 10 mg/kg per day (N = 10), for 20 da ys. Controls (N = 10) received saline. 2. Plasma testosterone level (m easured by radioimunoassay) decreased significantly in sympathectomize d rats from 4.11 +/- 0.57 to 1.76 +/- 0.37 ng/ml (5 mg/kg G) and to 1. 17 +/- 0.26 ng/ml (10 mg/kg G). Plasma levels of luteinizing and folli cle-stimulating hormones and of prolactin were unaltered. 3. Chemical denervation caused a significant decrease in ventral prostate wet weig ht from 74.3 +/- 5.5 to 59.3 +/- 4.7 mg (5 mg/kg G) and to 54.6 +/- 4. 1 mg (10 mg/kg G) and in seminal vesicle wet weight from 36.5 +/- 6.8 to 31.7 +/- 5.2 mg (5 mg/kg G) and to 21.3 +/- 1.6 mg (10 mg/kg G). 4. The potential secretory activity of the prostate (measured in terms o f fructose content) decreased significantly in guanethidine-treated ra ts from 0.38 +/- 0.02 to 0.30 +/- 0.02 mg/g (5 mg/kg G) and to 0.20 +/ - 0.02 mg/g (10 mg/kg G). The seminal vesicle fructose content (0.33 /- 0.04 mg/g for controls), however, was not altered by chemical dener vation. 5. Our data suggested that sympathetic neurons may be involved in the control of LH receptors, at least in the prepubertal phase of sexual development. They may also be directly related to growth and se cretory activity of the male accessory sex glands.