[Morphofunctional state of reproductive system of ageing male rats in case of using nanocerium].

The influence of nanocrystalline cerium dioxide (NCD, 1 and 100 mg/kg per os daily for 10 days) on morphofuctional state of reproductive system was investigated in ageing male rats. It has been established that activation of hormone-producing testicular Leydig's cells, as well as of secretory and proliferative processes in prostate, underlies the stimulating effect of NCD at a dose 1 mg/kg on hormonal function of testis and spermatogenesis of ageing male rats. NCD used at a dose 100 mg/kg had no significant effect on the assessed indices of morphofuctional state of reproductive system.

[Effects of cytokine-like polypeptide EMAP II and flutamide on the testosterone-stimulated prostate of castrated rats].

The effects of separate and combined administration of cytokine-like polypeptide EMAP II and flutamide, a nonsteroid antiandrogen, on morphology and function of the accessory sexual glands in castrated rats stimulated with testosterone propionate were studied. We found antiangiogenic, procoagulating and proapoptotic effects of EMAP II in the ventral prostate. Combined administration of the preparations enhanced their antiprostatic effects, which were manifested in inhibition of the androgen-dependent processes in prostate tissues, changes in proliferation and apoptosis, DNA, RNA and protein contents. We conclude that combined administration of EMAP II and flutamide can be used for development of new therapeutic modalities in prostate cancer.

[Effect of chronic stress during puberty on the reproductive system of female rats with experimental hyperandrogenicity].

Effects of chronic stress (daily 30-min immobilization) on 35-45 days of life and its combination with androgenization (implantation of testosterone-containing capsules on 33rd day of life) on reproductive system of 2.5 month old female rats were studied. The term of sexual maturation, estrous cycles regularity and structure, blood plasma levels of testosterone, progesterone and androstenedione as well as ovarian histology were examined. Androgenization resulted in the blood plasma testosterone level increase and the androstenedione level decrease, development of oligo- or anovulatory condition characterized by disorders or discontinuation in estrous cyclicity. We also detected abrupt reduction or absence of postovulatory luteal bodies, cysts formation and ovarian interstitial tissue overgrowth. All experimental animals had normal blood plasma corticosterone level. Stressed rats had no considerable changes in reproductive system except of some cyclicity disorders. Stressed against androgenization rats demonstrated delayed pubescence, an increased number of ovarian cysts along with attenuation ofandrogenization-caused negative effects on the sexual cyclicity.

[Enhancing effect of androgen receptor antagonist on gonadotropic inductors of ovulation in rats with polycystic ovaries].

Hormonal indices, phase pattern of estrous cycles, and histological structure of the ovaries were studied in female rats with polycystic ovaries caused by subcutaneous implantation of Silastic capsules with testosterone after consecutive treatment with non-steroid antiandrogen, flutamide (flutafarm), urinary FSH (menopur) and HCG (choragon). It was shown that while the plasma testosterone level was increased, administration of the drugs in subtherapeutical doses interrupted persistent diestrus, renewed estrous cycle, gonadal and uterine weights, induced appearance of postovulatory luteal bodies and restored fertility. Therefore, antiandrogen potentiation of pharmnnaco-dynamic effect of the gonadotropins with regard to their ability to ovulation induction was found out.

[Sex characteristics of neuroendocrine effects of prenatal exposure to exogenous glucocorticoids].

The effects of hydrocortisone acetate treatment of rats during the last gestational week on neurochemical and morphological characteristics of the brain in early postnatal and mature offspring were studied. Disappearance of sexual differences both in aromatase and 5alpha-reductase activities and noradrenaline concentration in the preoptic area in 10-day old rats was found. Meanwhile a sexual dimorphism in serotonin metabolism emerged. In adult offspring, the prenatal exposure to glucocorticoids resulted in disappearance of sexual differences in neurocytes' nuclei volume in medial preoptic and suprachiasmatic nuclei. The adrenocortical reaction to noradrenaline infusion to the 3rd brain ventricle was absent in the experimental males and intensified in females. In males, adrenocortical reaction to restraint decreased while post-stress changes in hypothalamic noradrenaline concentration and hippocampal glutamate decarboxylase activity were not observed. In the similar experiments in females both the augmentation of adrenocortical reaction and inhibition of GABA-ergic system were revealed. The results obtained indicate the modifying effect of prenatal exposure to glucocorticoids on sexual dimorphism of neuroendocrine system.