Effects of Acute Graded Reductions in Testicular Blood Flow on Testicular Morphology in the Adult Rat1

Abstract

The effect of moderate reductions in testicular blood flow has not been studied systematically. The aim of this study was, therefore, to examine the effects of different degrees of blood flow reduction on testicular morphology and to determine how much flow can be reduced before damage occurs. The subcapsular testicular artery was partially ligated in the left testes of adult rats. Testicular blood flow was measured before, immediately after, and 5 h after the ligation using laser Doppler flowmetry. After 5 h of partial ligation, the testes were removed, and their morphology was examined and related to the degree of blood flow reduction. The number of in situ end-labeled- or TUNEL-positive (i.e., dying) germ cells and the volume density of intravascular polymorphonuclear (PMN) leukocytes were measured. When flow was reduced to approximately 70% or less of its pretreatment value, a dose-related increase in the number of dying spermatogonia and early spermatocytes was seen. The PMN leukocytes accumulated in testicular blood vessels after partial ligation, and the maximum number was observed in testes where flow was reduced by approximately 50% of the pretreatment value. In conclusion, early stages of spermatogenesis are sensitive to a moderate, acute reduction in blood flow. Discrete reductions in flow may, therefore, have a large impact on sperm production.

Serotoninergic system blockage in the prepubertal rat inhibits spermatogenesis development

“…As mentioned above, serotonin inhibits testosterone synthesis (Tinajero et al 1993), functions as a potent vasoconstrictor of the testicular subcapsular artery at physiological and elevated transmural pressures (Davis 1992) and decreases the blood flow and vasomotion (Collin et al 1996). The effects of an elevated testicular blood pressure include focal apoptosis of spermatogonia and primary spermatocytes (Bergh et al 2001); whereas, a reduction in testicular blood flow could induce testicular hyperemia and edema (Davis 1992). In the present study we did not observe testicular edema and apoptosis occurring in round spermatids.…”

The effects of carbon dioxide pneumoperitoneum on ovarian blood flow, oxidative stress markers, and morphology during laparoscopy: a rabbit model

“…As a result, laparoscopic procedures may cause a model of ischemia-reperfusion injury in the organs and tissues (4). In an experimental study on testes, it was shown that the testes are highly sensitive to ischemia, and germ cells may be severely hypoxic even after short-term microcirculatory disturbances, which affects testicular function (4,22). Similarly, the ovaries are also highly sensitive to ischemia.…”

Testicular Blood Flow and Plasma Concentrations of Testosterone and Total Estrogen in the Stallion after the Administration of Human Chorionic Gonadotropin

“…Testicular tissue is very sensitive to disruption of its nutritive supply, which is primarily via the hematogenous route. Several investigations in humans [1][2][3][4] and rats [5,6] have demonstrated an association between testicular blood flow and sperm quality. In addition to local mediators, hormones appear to be involved in regulation of testicular blood flow [6].…”