Effects of TNF-α Injection into the Ovarian Parenchyma on Luteal Blood Vessels in Rabbits

Abstract

It has been reported that tumor necrosis factor-α (TNF-α) derived from luteal macrophage is concerned with luteolysis. In the present study, to evaluate the correlation between TNF-α and regression of luteal blood vessels, recombinant human TNF-α (rh-TNF) was injected into the parenchyma of pseudopregnant rabbit ovaries. These injections were performed on day 7 of pseudopregnancy (functional luteal phase). Only Mg⁺⁺ and Ca⁺⁺ free phosphate buffer saline (PBS-) as the solvent was injected in the control group. Estimations of conditions in the luteal vessels after the injections was performed by observations of luteal vascular corrosion casts under a scanning electron microscope. Concentrations of serum progesterone before or after the injection were also assayed. In the control group, no change in the structure of luteal vessels was observed after PBS- injection, but regressing blood vessels with strictures, obstructions and rugged surfaces on the vessels were observed, and also concentrations of serum progesterone decreased noticeably after rh-TNF injection. These findings suggest that TNF-α plays a role in angiolysis through luteolysis in the rabbit corpus luteum.