Serum testosterone (T) levels in men decline with age while serum LH levels, as measured
by RIA, increase. To assess if the decline in serum T levels in healthy aging men is …

OBJECTIVE The mechanism underlying the slight hypoandrogenism associated with normal
ageing remains unclear. We have therefore examined age related changes in the activity of …

The influence of aging on the responsiveness to sex steroid hormones in men was studied
by comparing circulating gonadotropin concentrations, pulsatile LH release, and sex …

Testicular function declines with normal aging, while serum immunoreactive LH and FSH
levels increase. Since there are reports of an age-related decrease in the ratio of bioactivity …

Many studies have shown cross-sectional (and two small studies, longitudinal) declines in
total and/or free testosterone (T) levels, with age, in men. The extent to which decline in T is …

The influence of aging on serum LH and testosterone (T) pulse frequency and gonadotroph
sensitivity to an-drogen and estrogen feedback was studied in young (< 55 yr old) and …

Decreased testicular function occurs as a concomitant of aging in men and is accentuated
by the presence of systemic illness. Previous studies identified an intrinsic Leydig cell defect …

Cross-sectional studies have demonstrated a decline in testosterone and free and
bioavailable testosterone with age. This occurs in a majority of older persons without an …

Tissue available (bioavailable) testosterone (T) includes circulating free T (FT) and albumin-
bound T. A reasonable assessment of bioavailable T can be made by using 50% ammonium …

The influence of aging on episodic LH secretion and the release of LH and FSH after LRH
administration was studied in 14 healthy men, aged 65–80 yr. Mean morning serum …