Biomedical subjects

K M Ataya

Publications and source records attributed to K M Ataya.

25 records · Page 2Linked to original sources

PubMed1988

Effect of "activated" cyclophosphamide on mouse oocyte in vitro fertilization and cleavage.

To investigate the involvement of oocytes in the mechanism of chemotherapy-induced ovarian failure, ovulation was induced in mice using pregnant mares' serum gonadotropin and human chorionic gonadotropin. Oocytes (with cumulus) were incubated for 4 hours with "activated" cyclophosphamide, 4-hydroperoxycyclophosphamide (PCTX) at 0, 1, 10, 100, and 500 micrograms/mL. Oocytes were then washed, fertilized with sperm obtained from nontreated male proven breeders, and incubated for 4 days. "Activated" cyclophosphamide inhibited dissolution of the cumulus and reduced fertilization and early cleavage rates in a dose-related manner. The data demonstrate that exposure of oocytes to cyclophosphamide metabolites in vitro adversely affects oocyte function. Oocytes may be involved in the mechanism of cyclophosphamide-induced ovarian failure.

Animals↗

PubMed1988

Clinical value of prolactin bioassay in euprolactinemic reproductive disorders.

To examine the disparity between clinical presentation and prolactin (PRL) measured by radioimmunoassay (RIA), serum samples from 128 patients with galactorrhea and/or reproductive disorders were evaluated by RIA for immunoassayable PRL (RIA-PRL) and by Nb2 lymphoma cell proliferation assay for bioassayable PRL (bioassay-PRL). One hundred fifteen patients had normal RIA-PRL and 13 patients had high RIA-PRL (greater than 25 ng/ml). Twenty patients had galactorrhea, two of whom had hyperprolactinemia. The reproductive disorders in female patients included infertility, amenorrhea, oligomenorrhea, irregular menstrual cycles, and luteal phase defects. Six oligospermic males also were studied. Twenty-three male and female volunteers with no evidence of reproductive disorders served as controls. Appropriate comparisons showed that PRL bioassay/RIA ratio, an index of agreement between the two assay systems, did not differ for the various patient groups compared with controls. It is concluded that Nb2 lymphoma bioassay does not provide additional diagnostic value to RIA in defining the cause of euprolactinemic galactorrhea and/or reproductive disorders.

Biological Assay↗

PubMed1985

A luteinizing hormone-releasing hormone agonist for the prevention of chemotherapy-induced ovarian follicular loss in rats.

In an attempt to prevent chemotherapy-induced ovarian follicular loss, [D-Leu6, des-Gly10-NH2]-luteinizing hormone-releasing hormone ethylamide (LHRHa) was given subcutaneously to Sprague-Dawley cycling female rats in two daily doses of 2.5 micrograms starting 2 days prior to and concomitant with cyclophosphamide (CTX) (5 mg/kg/day for 21 days). Four groups of female cycling rats (10 in each) received either no treatment, CTX alone, CTX + LHRHa, or LHRHa alone. One ovary from each animal was serially sectioned, stained, and examined for the number and size of follicles. CTX produced a significant reduction in the total number of follicles. The pool of growing follicles (medium to large, greater than 30 microns in diameter) appeared to be vulnerable to the cytotoxic effect of CTX. LHRHa resulted in a significant reduction in the number of medium-to-large follicles and an increase in the number of small follicles. When given in combination with CTX, LHRHa significantly further reduced the number of medium-to-large follicles, significantly increased the number of small follicles, and resulted in an increase in the total number of follicles. Chronic LHRHa treatment resulted in functional deprivation of follicles from gonadotropins, thus halting the process of recruitment from the quiescent pool of primordial follicles into the CTX sensitive pool and thereby preserving the functional potential of the ovary.

Animals↗

PubMed1983