The objective of the present study was to investigate endocrine control of LH in postpubertal boars with large testes. Eight boars with the highest estimated paired testis weights from a line selected for large testes and nine boars from a line selected at random were used. Blood samples were collected over a 13-h period at weekly intervals for 4 wk. Samples were collected at 12-min intervals f...

Cissus populnea are plants associated with a myriad of medicinal uses in different parts of the world and are good sources of carotenoids, triterpenoids, and ascorbic acid. The antioxidant properties and inhibitory effect of water extractible phytochemicals from stem bark of C. populnea on FeSO(4) and sodium nitroprusside- (SNP-) induced lipid peroxidation in rat testes were investigated in vit...

Quantitative histology of the descended testis of unilateral cryptorchid bucks was compared with testis of normal bucks to evaluate the reproductive potentials of the scrotal testis in unilateral cryptorchids, using light microscopy techniques. The contralateral scrotal testes of the unilateral cryptorchids and the testes of the normal bucks contained profiles of seminiferous epithelium and eac...

The recently discovered estrogen receptor-beta (ERbeta) is expressed in rodent and human testes. To obtain insight in the physiological role of ERbeta we have investigated the cell type-specific expression pattern of ERbeta messenger RNA (mRNA) and protein in the testis of rats of various ages by in situ hybridization and immunohistochemistry. In fetal testes of rats 16 days postcoitum and test...

The aim of this study was to investigate the effects of acute and repeated immobilization stress on oxygen consumption of the isolated interstitial rats' testes cells (ISC). The ISC testes cells were isolated acording to Anakwe et al. The oxygen consumption by ISC testes was measured polarographically in vitro with a Clark-type oxygen electrode (YSI-5331, Yellow Springs Instrument), which was d...

Testicular cell transplantation has been widely used to investigate the biology of spermatogonial stem cells, production of transgenic animals, and restoration of fertility in rodent models. One critical step in successful transplantation is the preparation of the recipient testes. Busulfan has been widely used, but irradiation has been often suggested as an alternative. There have only been li...

The effects of the proopiomelanocortin-derived opioid peptide, beta-endorphin (beta-EP), and of the opioid antagonist, naloxone (NAL), on both basal and pituitary-stimulated androgen secretion from superfused quiescent and active testes were assessed in the adult lizard, Podarcis sicula. In the absence of the homologous pituitary, in vitro treatment with beta-EP and/or NAL did not affect basal ...

Comparative analyses suggest that a variety of ecological and behavioural factors contribute to the tremendous variability in extrapair mating among birds. In an analysis of 1010 species of birds, we examined several ecological and behavioural factors in relation to testes size; an index of sperm competition and the extent of extrapair mating. In univariate and multivariate analyses, testes siz...

Testicular teratomas can be experimentally induced in some strains of mice by grafting 12.5-day male genital ridges to the testes of adults. The grafts develop into testes and most of them have teratomas. The cells of 12.5-day foetal gonads were dissociated and the germ cells and somatic cells were separated. When germ cells were reaggregated with somatic cells and implanted in adult testes, th...

The formation of testes or ovaries in the mammalian embryo is critical in determining sexual identity and the ability to reproduce. Recent studies have begun to illuminate the cellular signalling events required for development of functional testes.