Publisher Summary This chapter discusses gonadotropins and plasma testosterone in
senescence. An investigation described in the chapter showed that the testis was capable of …

Extensive biologic and clinical investigations of the process of aging have demonstrated a
general decrease in testicular activity with increasing age. With the recent elaboration of …

To determine the basis for the decline in testosterone production by the aged testis,
intratesticular unconjugated steroids, including testosterone, pregnenolone (3β-hydroxy-5 …

Measurements of testosterone concentrations in peripheral and spermatic venous blood
have yielded conflicting results concerning testosterone production in elderly men. To further …

The relation of neuroendocrine functions to the reproductive decline was compared in
human subjects and in rats of both sexes. The ovaries of rats remain potentially functional …

The concentration of sex and gonadotropic hormones in blood plasma of 280 reasonably
healthy men aged 20–105 was determined using radioimmunoassay kits. Compared to men …

In order to clarify the age-related functional changes of the hypothalamic-pituitary-gonadal
axis in men, the negative feedback control of serum gonadotrophin by sex steroids was …

Abstract Androstenedione (Δ), Testosterone (T) and Dihydrotestosterone (DHT) have been
measured by radioimmunoassay in spermatic venous plasma from 38 men aged from 17 to …

" If the degenerations, if the senile alterations are disease, a day will come when it is
possible to cure them.... the question is certainly not whether the injections [of aqueous …

Although alterations of circulating sex steroids have been reported in aging men, it is not
known to what extent reported changes may represent effects of variables other than aging …