Presence of Bacteria in Porcine Follicular Fluid and Their Ability to Generate an Inhibitor of Follicle-Stimulating Hormone Binding to Receptor

Follicular fluid obtained from porcine ovaries collected at slaughter and distributed by the National Institutes of Health was contaminated by bacteria which appeared to be of intestinal origin. This follicular fluid showed increased follicle-stimulating hormone binding inhibition (FSH-BI) activity following incubation under conditions which facilitated bacterial growth. No such increase in FSH-BI activity was observed following incubation of follicular fluid from which bacteria were removed by repeated filtration. Our data suggest that bacteria found in the follicular fluid were capable of generating a substance with FSH-BI activity. This substance has an apparent molecular weight greater than 6000, based on membrane diafiltration studies. The possible presence of bacteria in follicular fluid and their ability to generate a substance which interferes with FSH binding to receptor should be considered in studies on factors in follicular fluid that are considered to regulate ovarian function or development.