INTRAOCULAR OVARIAN ISOGRAFTS IN MALE MICE AND THEIR RESPONSE TO HUMAN PLACENTAL LACTOGEN

The luteotrophic activity of human placental lactogen (HPL) in non-primates was demonstrated by its ability to maintain the induced decidual reaction in hypophysectomized pseudopregnant rats (Josimovich, Atwood & Goss, 1963). In the mouse, HPL has been reported to induce hyperaemia of corpora lutea of ovulation in non-parous mice (Kavocic, 1968). However, because of the design of the study, it was not possible to determine the duration of hyperaemia in those HPL-induced corpora lutea. Ovarian isografts in male mice develop mature follicles that only rarely luteinize spontaneously. Such follicles luteinize upon the administration of luteinizing hormone (LH) and the resultant corpora lutea only show hyperaemia of function if a luteotrophic hormone is then given (Browning, 1968). The present investigation was undertaken to examine the hyperaemic response of ovarian isografts in male mice to HPL and to compare its luteotrophic activity with that of ovine pituitary prolactin. Male BALB/cCrl mice, 2 months old, received bilateral intraocular isografts of ovary from donors of the same age. Each ovary, when removed from the donor, was maintained in a Petri dish moistened with 0-9 % saline and was cut into eight approximately equal fragments. Eac