Response of Adult Rat Sertoli Cells and Leydig Cells to Depletion of Luteinizing Hormone and Testosterone

Publisher Website
Google Scholar
Abstract
Antisera to purified ovine LH (courtesy of Dr. H. Papkoff, potency-2.7X NIH-LH-S1) were prepared in rabbits and made monospecific by suitable absorption. In an initial experiment rats were sacrificed 1, 5 and 9 days after daily intraperitoneal injections of anti-LH serum. Rats from a second experiment were bled 3, 6, 12 and 24 h after a single injection. Normal rabbit serum (NRS) was injected into other rats as controls. Rete testis fluid was collected from the rats in the first experiment at the 5 day interval. As early as 3 h after injection of anti-LH, serum testosterone (T) levels fell to 17 percent of control values and they remained at this low basal level up to 24 h. Following 5 daily injections of anti-LH, serum T values were 0.20 ± 0.02 ng/ml vs 1.80 ± 0.31 in the controls. At this interval rete testis fluid T was 14.08 ± 1.2 ng/ml compared to 41.75 ± 8.0 in the NRS group. Twenty-four hours after one injection of anti-LH serum Leydig cell area was reduced by 29 percent. The most striking fine structural alteration was a marked diminution in the amount of smooth endoplasmic reticulum. In the seminiferous epithelium the first sign of damage following T reduction was a retention of late spermatids by the Sertoli cells. This was noted at the 5 day interval. Thus, the sperm release function of Sertoli cells appeared to be compromised. Mid-pachytene spermatocytes in various phases of degeneration were also noted. The Sertoli cell function of phagocytosis was not visibly affected since the degenerating germ cells were quickly engulfed and phagocytized. Fluid production by Sertoli cells continued as well. Within the Sertoli cell itself there was an apparent de-differentiation of the nucleus after T depletion. Normally the adult Sertoli cell nucleus exhibits numerous deep nuclear envelope infoldings imparting to it a highly irregular appearance. At the 9-day interval, the nuclei assumed a more spherical shape, although it was still possible to find nuclear membrane indentations. Other cytoplasmic Sertoli cell alterations included an increase in the amount of lipid droplets, an increase in the number of cup-shaped mitochondria and an apparent decrease in the amount of smooth endoplasmic reticulum. These results demonstrate that the Sertoli cells are visibly affected at early intervals following hormonal depletion and suggest that the damage upon the germinal elements may be secondarily transmitted.