The agonist (d-leu-6,des-gly-10)-LHRH-ethylamide does not protect the fecundity of rats exposed to high dose unilateral ovarian irradiation

Attempts to protect the ovary from the toxic effects of radiation and chemotherapy are relevant to the management of the young patient with cancer. Previous studies in a variety of animal species with several types of agonists of GnRH have shown promise in affording gonadal protection using indirect indices of reproductive function. The current investigations are based on these observations. Female rats were treated with (d-leu-6,des-gly-10) LHRH-ethylamide (GnRHa) from day 22 to day 37 of life. Sham-irradiation or unilateral irradiation of the left ovary was performed on day 30. The animals were mated following resumption of cycles and sacrificed on day 21 of pregnancy. There was no significant effect of ovarian artery ligation. Radiation reduced ovarian function ipsilateral to the radiation. GnRHa alone did not affect reproductive performance significantly. GnRHa and radiation combined resulted in no reproductive protection but augmented the damage done to the ipsilateral ovarian weight and to numbers of corpora lutea and fetuses. Under these experimental circumstances the agonist provided no protection.