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To evaluate the effects of active immunization against gonadotropin-releasing hormone (GnRH) on the ultrastructure of the rat ventral prostate, male Sprague-Dawley rats received three consecutive intramuscular injections of 10 μg/100g body weight (D-Lys)-GnRH-diphtheria toxoid conjugate (GnRH-DT vaccine). Following immunization, test animals developed sufficiently high antibody titres to block the pituitary gonadal axis. Consequently testosterone values dropped to the levels in castrates. This therapy leads to atrophy of the prostate. Following immunization a strong immunological response, indicating the presence of considerable amounts of a GnRH-like peptide, was observed in the ventral prostates as early as 14 days after the first injection of GnRH-DT. Immunoneutralisation of GnRH-like activity may contribute to the effects observed. [ABSTRACT FROM AUTHOR]

The present study examines the ultrastructure of ejaculated spermatoza from bonnet monkey, Macaca radiata under noraml conditions, with gossypol treatment and during recovery from such treatment. Monkeys were fed orally with gossypol acetic acid (GAA) for 3 months (4 mg/monkey/5 days a weak). Semen samples collected by electroejaculation, and the spermatozoa were examined using both light and electron microscopy. The degree of motility was also noted by Kalla et al. [12]. Ejaculated spermatoza were immotile 90 days after GAA treatment, but little evidence for any abnormality in the spermatozoa could be seen by light microscopy. Some ultrastructural changes were observed, but not to the extent previously reported in spermatozoa of Macaca fascicularis [23]. After termination of treatment, semen samples were obtained every 5th day until sperm count and motility recovered to the normal level. After 90 days only a small proportion of spermatozoa showed abnormal structure. We conclude that in a subhuman animal model gossypol induced effects on sperm motility and morphology are reversible. [ABSTRACT FROM AUTHOR]

In this study we investigated the effect of low and high dosages of a potent LHRH agonist on the pituitarygonadal axis with special consideration to the effect on the tubular compartment of the testis. Included were 3 treatment groups: the probands in Group I were treated with 3 x 50μg HOE 766/week intranasally for 5 months; in Group II with 3 x 100 μg HOE 766 intranasally/day for 6 months and in Group III with 3x200μg HOE 766 intranasally plus 5mg fluoxymesterone orally/day for 5 months. With the low dose (Group I) no changes in the seminal parameters measured could be observed whereas LH and FSH levels increased in plasma, testosterone showed no change compared to preatreatment values. When high dosages/day of a potent LHRH agonist were administered without androgen replacement (Group II) pronounced decrease of LH and FSH took place, the testosterone plasma levels approached the female range. Spermatogenesis was arrested. The agonist plus androgen replacement (Group III) counteracted the suppression of spermatogenesis. [ABSTRACT FROM AUTHOR]

Gossypol acetic acid in a concentration of 1,000 μg/ml solvent is able to immobilize 1 ml of native bull semen (sperm concentration: 8.5×10/ml; motility rate: 87.4%) within 30 min. After GAA treatment the spermatozoa show severe morphological damage on the membrane system, on the acrosomal complex and on the tubular complex of the end piece. The working mechanism of GAA can be assumed to be inactivation of enzyme activities or in direct reactions with plasma membrane material. [ABSTRACT FROM AUTHOR]

The present investigations were carried out to show the histological and ultrastructural alterations in rat testes 10 weeks after gossypol acetic acid treatment (dose: 30 mg gossypol acetic acid/kg/day). The morphological findings in the interstitial compartment were compared with the data from studies carried out to investigate the testosterone biosynthesis in gossypol acetic acid treated rats. No morphological changes in the epididymal and vasal epithelia were found; however, the germinal epithelial cells showed vacuolisation, pycnosis, disconnections of junctions, cytolysis and exfoliation of germ cells from the epithelium. The Sertoli cells were affected, too. Gossypol acetic acid seemed to stimulate the physiological activity pathologically; cellular organelles as mitochondria, endoplasmic reticulum, lysosomal vacuoles, pigment granules and nuclei were either enlarged in size and number or malformed in shape. The cellular contact was often restricted to spots or completely disconnected. If gossypol acetic acid was administered for a longer period of time some Sertoli cells were found to be unable to withstand the toxic stimulus, and the cells became necrotic too. In contrast to the toxic process in the germinal and Sertoli cells the Leydig cell compartment did not show any changes in fine structure, and therefore testosterone biosynthesis is presumed to be intact. [ABSTRACT FROM AUTHOR]

The effect of BCG-induced orchitis on the structure of the seminiferous tubules in rats and rabbits was investigated by light and electron microscopy. The formation of cavities between Sertoli cells and the displacement of the cells of the spermatogenic cycle are the earliest changes to be observed. Individual Sertoli cells degenerate and separate from spermatocytes and spermatids. The latter form multinuclear complexes by a broadening of the intercellular bridges. The nuclei of spermatids undergo ring-like chromatin condensation in the rat and swelling in the rabbit. After the loss of spermatocytes and spermatids from the germinal epithelium, the remaining Sertoli cells have a very irregular shape and contain many residual bodies, which are probably derived from previously phagocytosed spermatids. They often contain crystalline inclusions. The nuclei of Sertoli cells show small chromatin condensations. In the rabbit, the tubular wall increases considerably in diameter. In the vicinity of a granuloma in the interstitium caused by BCG inflammatory cells accumulate around the wall of the seminiferous tubules. Although the basal lamina seems to be an obstacle, penetration of macrophages into the tubular lumen could be observed. However, this occurred only after the degeneration of the germinal epithelium. [ABSTRACT FROM AUTHOR]

Collagenase activity in human bladder carcinomas was measured against C-labeled collagen as substrate. Enzyme activity in vivo increased with the degree of penetration of the bladder wall. It was not detectable or low in the cases of superficially infiltrating tumours (A, B1, B2) and high in the cases of deeply infiltrating tumours (C, D). These results suggest that collagenase activity of advanced tumours is predominantly expressed in the perivesical layer of the bladder wall. A quantitative estimate of this enzyme may thus help to distinguish between Stage B and Stage C tumours. [ABSTRACT FROM AUTHOR]

Radioimmunoassays for 2 synthetic progestins (Ethinyl-norgestrienone, R 2323 and medroxyprogesterone acetate, MPA) are demonstrated. 10 patients aged 31 to 72 years were treated with ethinyl-norgestrienone with different schedules and 3 men suffering from benign prostatic hypertrophy were treated with medroxyprogesterone acetate. Plasma levels of testosterone, LH, FSH were monitored before, during and after treatment. [ABSTRACT FROM AUTHOR]