Origin of Estrogen in Normal Men and in Women with Testicular Feminization*

Abstract

The purpose of this study was to quantify the various sources of estrone (E1) and 17 beta-estradiol (E2) production in normal men and in women with testicular feminization. The mean production rate of E1 in four young adult men was 58 micrograms/24 h, while that of E2 was 44 micrograms/24 h. In these men, E1 production could be accounted for totally by extraglandular formation through 1) aromatization of plasma androstenedione, 2) conversion of E2 which was formed from the aromatization of plasma testosterone, and 3) conversion of secreted E2. In these men, only 12 micrograms or less of E2 production could not be accounted for by extraglandular formation from plasma C19 precursors, and is presumed to have arisen by testicular secretion. In six women with testicular feminization, the mean production rate of E1 was 99 micrograms/24 h, while that of E2 was 77 micrograms/24 h. THe amount of E2 production that arose by glandular secretion could be computed in four of these women and was considerably greater than that found in the young adult men. In these women with testicular feminization, an average of 44 micrograms/24 h E2 could not be accounted for by extraglandular formation and is presumed to have arisen by testicular secretion. The mean plasma production rate of testosterone in the normal men was 5.7 mg/24 h, while that in the women with testicular feminization was 8.3 mg/24 h. However, the range of plasma production rates of testosterone in the women with testicular feminization was large (1.3--17.0 mg/24 h).

A direct approach to the estimation of the origin of oestrogens and androgens in elderly men by comparison with hormone levels in postmenopausal women

“…These estimates agree with the results of earlier experiments using radiolabelled hormone infusion techniques. MacDonald et al (24) calculated that the daily urinary E2 excretion in men aged 26 -35 years originates from direct secretion by the testes (13%) and from peripheral production from circulating testosterone (38%) or androstenedione (49%). Urinary E1 is only peripherally produced via conversion of testosterone (32%) or androstenedione (68%).…”

Social regulation of adult neurogenesis in a eusocial mammal

“…Most work on estrogens and neurogenesis has been done with estradiol, a potent estrogen synthesized in the ovaries, adrenal glands, brain, and Leydig cells of the testis (Grodin et al, 1973;MacDonald et al, 1979;GarcieSegura et al, 1999). In line with the presence of estrogen receptor alpha and beta in the dentate hilus and GCL respectively (Blurton-Jones et al, 2004), the female bias in hippocampal cell proliferation may depend on estradiol, with suppressed proliferation seen immediately after ovariectomy .…”

Familial gynecomastia with increased extraglandular aromatization of plasma carbon19-steroids.

“…Gynecomastia is a common finding among pubertal boys; usually, it is limited to a nodule of subareolar tissue, and ordinarily the breast enlargement begins during the early stages of the pubertal process and thereafter regresses within [6][7][8][9][10][11][12][13][14][15][16][17][18] mo. Levels of plasma testosterone (T),' estradiol-17# (E2), serum luteinizing hormone (LH), and follicle-stimulating hormone (FSH) in boys with pubertal gynecomastia are not significantly different from those in unaffected boys (1), although a relative increase in the level of plasma E2 compared with that of T during certain times of the day has been found (2).…”