TRANSFERENCE OF CIRCULATING LABELED SERUM PROTEINS TO THE FOLLICLE OF THE RAT OVARY

Rat whole serum, albumin, globulins and fibrinogen fractions were labeled with fluorescent dyes (sulforhodamine B, CI No. 45100, and fluorescein isothiocyanate); albumin was also tagged with radioactive iodine (I131). Labeled serum fractions were intravenously injected in adult female albino rats and their decay in the circulation and histological distribution in the ovaries was studied. As a complement histoimmunological techniques using labeled fluorescent antibodies against rat serum fractions were also applied to the ovary sections of intact rats as well as of rats previously injected with unlabeled serum fractions. It was observed : 1) Labeled whole serum, albumin and globulins decay in the circulation with a half-life value of 2.8 days for the first, 2.6 days for the second and 3.1 days for the last. 2) Parallel with the fast component of this time decline curve, serum fractions diffuse extravascularly in the ovary and appear in the zona pellucida and cytoplasm of the oocyte in the growing follicles, via thecal capillaries, intercellular spaces of granulosa layer and antrum. 3) Histoimmunological techniques suggest that also endogenous circulating serum fractions may be transmitted to the follicles following the same route.