The relationships between plasma gonadotropins, testicular gonadotropin receptors, and plasma testosterone were examined during neonatal life and throughout sexual maturation in the rat. The binding affinity of testicular LH receptors (2.4 X 10(10) M-1) was significantly higher than that of FSH receptors (2.1 X 10(9) M-1) at all stages of development. The concentration of FSH receptors in the testis reached a peak between 10-15 days of age, then fell to a constant level from 25-90 days. However, the testis content of FSH receptors increased continually with age and reached a plateau at day 60. Plasma FSH declined after birth to a nadir at 15 days, then rose rapidly to a peak at day 38, and fell to a plateau from day 50 through adult life. In contrast to the rapidly changing profile of plasma FSH during early maturation, alterations in plasma LH were less marked throughout development. Although a progressive rise in plasma LH concentration was observed between days 36-51, the simultaneous changes in testicular LH receptors and plasma testosterone were much more prominent. Testicular LH receptors showed a continuous increase in concentration and total number with advancing age and testis growth. The major rise in LH receptor concentration occurred between 15-38 days age, at the same time as the rise in plasma FSH concentration and the phase of rapid testicular growth. Plasma testosterone fell during the 8th-24th days after birth, then rose rapidly between days 35-55. The pubertal rise in plasma testosterone occurred about 15 days after testicular LH receptors began to increase and was coincident with the continuing rise in LH receptor content from day 35 until day 55 and with the progressive increase in plasma LH during this period. These observations have demonstrated that the early development of testicular FSH receptors in followed by a prominent rise in plasma FSH, with concomitant increases in testicular growth and LH receptor concentration. The resulting increase in gonadal sensitivity to LH could be responsible for the marked increase in secretion of testosterone which occurs during puberty in the presence of a relatively small change in the circulating LH concentration. The sequence of changes observed in gonadotropins and their testicular receptors is consistent with the view that FSH-induced testicular sensitivity to LH is an important factor in sexual maturation in the male rat.

No abstract

Testicular and ovarian functions were assessed in 33 patients with Hodgkin's disease 1 to 17 years after cessation of COPP chemotherapy with cyclophosphamide, vincristine, procarbazine, prednisone. Diagnostic procedures consisted of hormone measurements, interviews, and semen analyses. In women serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), 17 beta-estradiol, progesterone, prolactin, and in men FSH, LH, 17 beta-estradiol, testosterone, and prolactin were determined. Semen analyses were performed in all men. Information concerning pregnancies, pregnancy outcome, future fertility wishes, sexual functions, menstrual pattern, and incidence of premature menopausal symptoms was ascertained by interview and questionnaire. Nineteen of 19 (100%) men showed elevated serum FSH levels between 715 and 1910 (median 1095) ng/ml and azoospermia, 1 to 11 years after therapy. Serum levels of testosterone were within normal limits in 18/19 (95%) of the men, and LH values were normal in all men. Permanent ovarian failure occurred in 8/14 (57%) women, causing infertility and premature menopausal symptoms. The incidence of ovarian failure in women over 24 years was 86% (6/7) versus 28% (2/7) in those under 24 years at the time of treatment. In women receiving estrogen replacement, incidence and severity of these symptoms were significantly reduced. Of 14 women 3 (21%) became pregnant and delivered 5 healthy children after treatment. Our results suggest irreversible sterility and normal Leydig cell function after COPP chemotherapy in all men. Drug-induced ovarian failure was age-related and caused premature menopausal symptoms, detracting from the quality of the patient's life. To reduce premature menopausal symptoms and to prevent adverse cardiovascular and metabolic late sequelae, hormonal replacement is indicated. Pregnancies ending in normal live births can be achieved after COPP chemotherapy in young women. In both men and women, serum FSH and LH levels proved to be feasible markers to determine degree and duration of endocrine and reproductive gonadal injury after chemotherapy.

The impact of aggressive chemotherapy on reproductive and endocrine gonadal function was studied in ten women and ten men with acute lymphoblastic leukemia (ALL) or acute undifferentiated leukemia (AUL) in complete remission. Hormone determinations, sperm analyses, measurements of basal body temperature, and interviews with a standardized questionnaire were used for diagnostic evaluation. Elevated serum follicle-stimulating hormone (FSH) levels and azoospermia were seen in all male patients after completion of induction and consolidation therapy as a result of germ cell and stem cell loss. Recovery of spermatogenesis, as indicated by normalization of serum FSH values and sperm density, occurred in the second year of maintenance therapy in all men. Serum testosterone and luteinizing hormone (LH) values remained within normal limits indicating resistance of Leydig cells to chemotherapy. All female patients showed normal serum levels of gonadal steroids and gonadotropins, as well as an adequate increase in basal body temperature after intensified chemotherapy, indicating intact follicle function and ovulation. Most patients reported normal sexual functions after induction and consolidation therapy. These results demonstrate that multidrug chemotherapy induced significant impairment of reproductive function in all male patients with early and complete recovery. In contrast, endocrine gonadal function was unaffected in men treated with ALL/AUL. In female patients, neither reproductive nor endocrine functions were influenced by aggressive chemotherapy.