Effects of Antisera on Fertilization of Mouse, Rat and Hamster Eggs

The effects of rabbit antisera against denuded eggs (anti-egg) and isolated zona-pellucidae (anti-zona) on fertilization were studied in different strains of mice, rats and hamsters. Treatment of denuded eggs with either anti-egg or anti-zona serum caused a more pronounced precipitate on the zona pellucida of the mouse than on that of the rat or hamster eggs. The time required to dissolve the zona pellucida by Pronase was different between the two antisera treatments and the species studied. In the mouse, in vitro fertilization was completely inhibited by unabsorbed antizona or anti-egg serum absorbed with liver and kidney but not by anti-egg serum absorbed with ovary. Fertilization in vitro was not significantly inhibited in the rat and hamster by anti-egg serum, but was inhibited in hamster eggs in cumulus or in denuded rat and hamster eggs by anti-zona serum. A complete inhibition of in vivo fertilization in different strains of mice was observed after a single injection of anti-zona or anti-egg serum. A single injection of female rats with 10–30 mg of unabsorbed anti-egg serum or 0.3 ml anti-zona serum resulted in complete to partial inhibition of fertilization, however, similar treatment failed to inhibit fertilization in hamsters. It seems that rabbit antiserum to denuded eggs or isolated zona pellucida of mice is neither strain nor species specific.