TESTICULAR FEMINIZATION: CLINICAL, MORPHOLOGICAL AND BIOCHEMICAL STUDIES

Steroid metabolism in testes of patients with incomplete masculinization due to androgen insensitivity or 17 beta-hydroxysteroid dehydrogenase deficiency and normally differentiated males

For purposes of establishing suitable controls in studies of patients with a suspected enzyme deficiency, activities of enzymes involved in the biosynthesis of testosterone were compared in testes of patients with androgen insensitivity syndrome (AIS) and normally differentiated males with carcinoma of the prostate (Ca prostate) or testis (Ca testis). Activities of 17,20-desmolase and of 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) were higher in the testes of pre-, peri- or postpubertal patients with AIS than in elderly men (58-80 yr) with Ca prostate. Activities of 17 beta-HSD (reductive direction) and 3 beta-HSD tended to be higher in peri- or postpubertal than in prepubertal patients with AIS. Activity of 3 beta-HSD was low in the patient with Ca testis. In a peripubertal (12 yr) patient with incomplete masculinization due to a severe deficiency of 17 beta-HSD, reductive activity of 17 beta-HSD was very low compared with that of patients with Ca prostate, Ca testis or AIS. In contrast, in testes from the younger sibling (4 yr), in whom the deficiency of 17 beta-HSD was less severe, 17 beta-HSD reduction of dehydroepiandrosterone was as high as that of men with Ca prostate, yet deficient in comparison with that of more closely age-matched patients with AIS. This emphasizes the desirability of using age-matched tissue for control purposes in enzyme studies.

Steroids in spermatic and peripheral vein blood in testicular feminization

Steroid secretion by the testes in three postpubertal patients with testicular feminization was studied by comparing the steroid concentrations in spermatic and peripheral blood samples obtained prior to gonadectomy. Testosterone, dehydroepiandrosterone (DHEA), and androstenedione were the predominant steroids secreted by these testes. Values for spermatic vein testosterone (60 to 700 nmoles/liter) were lower than those previously reported for normal men, but values for DHEA (20 to 240 nmoles/liter) and androstenedione (30 to 250 nmoles/liter) were within the range found in normal men. The testes of these three patients also secreted pregnenolone, progesterone, 17 alpha-hydroxyprogesterone, dihydrotestosterone, testosterone sulfate, and estradiol. After gonadectomy, the plasma concentration of estradiol declined considerably less than that of testosterone, indicating that estrogen formation from adrenal precursors continued after gonadectomy in these patients.

Early cytodifferentiation of human prostatic urethra and Leydig cells

The ultrastructure of the urethral epithelium and mesenchyme of the 6- to 9-week-old human embryos was studied in order to reveal early morphological signs of prostatic development. The morphological changes of the urethral wall were correlated with the cytodifferentiation of the Leydig cells of the same embryos. Throughout the study the urethral epithelium had two or more layers of cuboidal cells. The ultrastructure of the cells was primitive and they did not achieve characteristics of the secretory prostatic cell. The surface cells had well developed apical junctions and slender cytoplasmic processes projecting into widened intercellular spaces appeared during the developmental period. The urethral mesenchyme showed the most salient changes. The mesenchymal cells adjacent to the urethral epithelium differentiated in the ninth week inot fibroblast-like cells with an elongated shape and cytoplasmic processes. Granular endoplamic reticulum appeared in the cytoplasm and collagen fibers were seen in the intercellular space. Mesenchymal cell processes contacting the continuous basal lamina under the epithelium were present. No direct epithelio-mesenchymal cellular contacts could be seen. The differentiation of the mesenchyme before the epithelial outgrowths that the mesenchyme has an essential role in the glandular development. Electron microscopic study of the Leydig cells showed that the amount of agranular endoplasmic reticulum increased considerably in the ninth week. This agrees with earlier biochemical findings on the capability of Leydig cells to produce androgens by this time. The temporal relationship between the cytodifferentiation of Leydig cells and the urethral wall is consistent with the idea that in the human, fetal androgens induce prostatic development.

Effects of two structurally different antispermatogenic compounds on the synthesis of steroids in rat testes

The influence of two drugs with antispermatogenic properties on steroid biosynthesis has been studied in rat testes in vitro with pregnenolone as the substrate. 20-438, an indenopyridine derivative increased the relative conversion of pregnenolone to progestins and estradiol, whilst decreasing the conversion of substrate to testosterone and androstenedione. PMHI, a pipecolinoindane derivative, reduced testosterone levels in the testes without altering the relative conversion of pregnenolone to various steroids. This suggests that the agent is partially inhibiting the biosynthesis of androgen precursors leading to a testosterone deficiency in testicular tissue which may result in reduced spermatogenesis.

Ultrastructural study of testis in testicular feminization

Testicular tissue was investigated by electron microscopy in a case of testicular feminization. The seminiferous tubules were lined by spermatogonia and by Sertoli cells. Spermatocytic maturation was not observed. Leydig cells were numerous and contained well developed, abundant vesicular smooth-surfaced endoplasmic reticulum and large mitochondria with tubulovesicular cristae. Reinke crystalloids were absent. The ultrastructural findings were consistent with the assumption that Leydig cells were under adequate stimulation and were in a stage of active secretion. Hence, the results seem to indicate that testicular endocrine function was maintained in the studied case.

Steroid excretion and metabolism by gonadal tissue from a subject with testicular feminization syndrome

The initial clinical, pathological, and hormonal investigation of a patient with testicular feminization syndrome is described. Incubation of gonadal tissue with various radioactive substrates, together with the isolation and identification of the resulting metabolites, was demonstrated a high capacity to synthesize testosterone. Two biosynthetic pathways were demonstrated, originating from progesterone and pregnenolone. These are essentially similar to those of the normal adult testes. Low levels of activity were found in the phenolic fractions and no measurable production of oestrone, oestradiol, or oestriol was found.

Estradiol and testosterone secretion by human, simian, and canine testes, in males with hypogonadism and in male pseudohermaphrodites with the feminizing testes syndrome

The role of the human testis in the production of 17beta-estradiol (E(2)) was investigated by determining the concentration of E(2) and testosterone in peripheral and spermatic vein plasma samples. Specimens were obtained from eight normal men, three men with hypogonadism, and two patients with the incomplete form of the feminizing testes syndrome. For comparison, similar studies were performed in four monkeys, 10 mongrel dogs, and 4 additional dogs who were given 1000 IU of human chorionic gonadotropin/day for 5 days. Plasma E(2) was measured by radioimmunoassay utilizing sheep anti-E(2) serum preceded by ether extraction and thin layer chromatographic separation of plasma steroids. Procedural blanks, which were subtracted from all reported values were 14.1+/-0.74 (SEM) pg for deionized water and 13.1+/-0.66 pg for charcoaladsorbed pooled male plasma. Pooled male and pooled female control plasmas averaged 17+/-0.71 pg/ml and 95+/-6.9 pg/ml, respectively; individual adult male specimens ranged between 8 and 28 with a mean of 18+/-1.4 pg/ml. In the eight normal men, the mean peripheral vein E(2) concentration was 20+/-1.6 pg/ml, while the spermatic vein concentration was 50 times as great, 1049+/-57 pg/ml. All three patients with testicular abnormalities had low spermatic vein E(2) concentrations (160, 280, and 416 pg/ml). Lesser E(2) gradients were found across the simian (3-fold) and canine (approximately 12-fold) testes. Testicular testosterone gradients (human 110-, simian 10-, and canine 77-fold) were greater than the E(2) gradients in all three species. In four dogs, HCG treatment elicited a 6-fold increase in peripheral and a 9-fold increase in spermatic vein testosterone concentrations; however, peripheral and spermatic vein E(2) concentrations did not differ from control values. Spermatic vein E(2) concentrations were > 4600 and 2210 pg/ml (post-HCG) in two patients with the incomplete form of the feminizing testes syndrome. Postorchiectomy, peripheral E(2) and testosterone concentrations fell precipitously in both patients, confirming the major contribution of the testes, in this syndrome, to circulating E(2) and testosterone. These studies provide direct evidence that the human testic secretes estradiol.

Conversion of blood androgens to estrogens in normal adult men and women

Continuous infusions of Delta(4)-androstenedione-7-(3)H and testosterone-7-(3)H have been used to demonstrate that these androgens are converted to estrone and 17beta-estradiol, and contribute to the circulating blood levels of these estrogens in normal males and females. The conversion ratio (ratio of concentrations of radioactivity of free product steroid [chi(-PRO)] and free precursor steroid [chi(-PRE)], both corrected for recoveries, after an infusion of radioactive precursor steroid) for androstenedione (precursor) to estrone (product) is 0.013 in males and 0.007 in females, and the conversion ratio for testosterone (precursor) to estradiol (product) is 0.0018 in males and 0.005 in females. The transfer constant, [rho](BB) (AE1), for androstenedione conversion to estrone ([rho](BB) (AE1) = per cent of infused androstenedione, precursor, converted to estrone, product, when infusion and measurement are both in blood) is 1.35% in males and 0.74% in females, and the transfer constant, [rho](BB) (TE2), for testosterone conversion to estradiol is 0.39% in males and 0.15% in females. Whether measured as conversion ratio or transfer constant, the peripheral aromatization of androstenedione takes place to a greater degree than that of testosterone, and, for the respective androgens, both the conversion ratio and [rho](BB) value are greater in males than females. For the androgen interconversions, [rho](BB) (AT) is 4.5% in males and 2.2% in females; [rho](BB) (TA) is 8.2% in males and 12.0% in females. Studies on the distribution coefficients (effective concentration in red cells/plasma) for precursor radioactivity were also made. In both males and females the distribution coefficient for androstenedione is 0.16-0.17 while that of testosterone is 0.01-0.03.