Topic:Leydig Cells
Leydig cells are specialized cells located in the testes of horses, responsible for the production of testosterone and other androgens. These cells play a role in the development and maintenance of male reproductive tissues and influence secondary sexual characteristics. Leydig cells are involved in the regulation of reproductive function by responding to luteinizing hormone (LH) stimulation, which triggers the synthesis and secretion of testosterone. This page compiles peer-reviewed research studies and scholarly articles that explore the structure, function, and regulatory mechanisms of Leydig cells in horses, as well as their impact on equine reproductive health and performance.
Effect of seasonal changes in Leydig cell number on the volume of smooth endoplasmic reticulum in Leydig cells and intratesticular testosterone content in stallions. Testes from 47 adult (4-20 years) stallions obtained in November-January (non-breeding season) and 41 adult stallions obtained in May-July (breeding season) were perfused with glutaraldehyde, placed in osmium and embedded in Epon 812. Percentage Leydig cell cytoplasm or nuclei in the testis was determined by point counting of 0.5 micron sections under bright-field microscopy. Testes from 6 randomly selected horses per season were processed for electron microscopy. The volume (ml) of SER/testis was calculated from the % SER in the cytoplasm % Leydig cell cytoplasm, and parenchymal volume. Numbe...
Impaired estrogen production by Leydig cells of the naturally retained testis in unilaterally cryptorchid boars and stallions. Estrogen production in vitro was compared for Leydig cells from cryptorchid and scrotal testes in boars and stallions. Animals with natural and experimental cryptorchidism were used. Purified Leydig cells were prepared from testes of mature animals by collagenase treatment and Percoll density gradients. After incubation for 3 hours (1 X 10(6) cells), estrone sulfate and estrone in the media were measured by direct radioimmunoassay. Androstenedione and testosterone in media extracts also were determined. Cells from the abdominal testis of unilateral cryptorchid boars and stallions showed impair...