Critical comment on the "trophic" influence of the effector organ on the sympathetic nerves of the male sex accessories of the guinea-pig

A further contribution to the question of trophic and hormonal influences on the noradrenaline content of the male reproductive tract: effect of combined androgen and estrogen treatment of prepuberally castrated rats

58 days old, prepuberally castrated, male rats were treated with estrogen, testosterone or a combination of both hormones for 18 days. The total noradrenaline (NA)-content of the male accessory glands was increased by the hormone treatments. This increase was smallest in the estrogen treated group and largest in the group treated with both estrogen and testosterone. The NA-concentration, however, followed the reversed picture i.e. it was largest in untreated castrated rats and smallest in the rats receiving both estrogen and testosterone. Neither treatment brought the NA-amount up to the level of uncastrated controls of the same age although the weights of the secondary sex glands of rats receiving both estrogen and testosterone exceeded those of uncastrated controls. Similar, but less definite changes were observed in vas deferens and cauda epididymidis. It is concluded that a developing target area exerts some trophic influence on the adrenergic neurons innervating it. However, the trophic influence exerted by the effector organ on the nerves is not of the kind, that the innervation density and NA-concentration of the organ always are maintained at a constant level.

Influence of age, growth, castration and testosterone treatment on the noradrenaline levels of the ductus deferens and the auxiliary male reproductive glands of the rat

The total amount of noradrenaline (NA) in the male accessories increases with normal growth of the organs and also with the age of the rat. The ductus deferens of the old rat has about twice as high NA concentration as that of the young rat. Castration of the prepuberal rat or the puberal rat leads to retardation or cessation, respectively, of the increase in NA amount of the male genital tract. Only in the old rat does castration produce a definite decrease in NA amount of the tract. Castration always raises the NA concentration of the sex accessories. Testosterone treatment of the puberal rat or the old rat produces minor or no increase, respectively, in total amount of NA of the male sex accessories. Testosterone treatment of old prepuberally castrated rats produces a marked increase in NA content of the male organs. It is concluded that androgens have no substancial direct effect on the adrenergic innervation per se, but affects the transmitter levels of the male organs indirectly through changes in number, size and relative proportion of the target cells of the adrenergic nerves i.e. the smooth muscle cells.