Altered ovarian progesterone secretion induced by cadmium fails to interfere with embryo transport in the oviduct of the rat.
The effect of Cadmium (Cd) on embryo transport through the oviduct and on ovarian progesterone (P) secretion were studied in the rat. Animals were given 2.5, 5, 10 mg/kg CdCl2 or 1.0 mL/kg NaCl sc on day 1 of pregnancy. On days 1, 2, 3, 4, and 5, they were anesthetized with pentobarbital, cannulae were inserted in one of the utero-ovarian veins, and 5-minute blood samples were taken from the ovary. Ovarian venous outflow was recorded, P was determined from the blood fractions, and secretion rates were calculated. P levels were determined in peripheral blood. Body weights and the wet weight of adrenals, ovaries, and oviducts were checked; oviducts and uterine horns were flushed; and number, location, and developmental stage of embryos were observed. Cd content of the oviducts was measured. Cd accumulated dose and time dependently in oviducts and induced a dose-dependent depression and delay in the rise of ovarian P secretion during days 1 through 5 of pregnancy. In the peripheral blood, P levels also failed to rise until day 4 of pregnancy in Cd-treated rats. In embryo transfer, however, no alteration could be observed. It is hypothesized that lack of vascular contact in the oviduct makes it possible for the preimplantation embryos to escape toxic effects of Cd.
Paksy
K
K
National Institute of Occupational Health, Semmelweis University Medical School, 2, Department of Obstetrics and Gynecology, Budapest, Hungary.
Varga
B
B
Náray
M
M
Olajos
F
F
Folly
G
G
D000818:Animals; D002105:Cadmium Poisoning / Q000503:physiopathology*; D004622:Embryo, Mammalian / Q000187:drug effects*; D047108:Embryonic Development / Q000187:drug effects; D005187:Fallopian Tubes / Q000187:drug effects*; D005260:Female; D009929:Organ Size / Q000187:drug effects; D010053:Ovary / Q000187:drug effects* / Q000378:metabolism; D010066:Ovum Transport / Q000187:drug effects*; D011247:Pregnancy; D011374:Progesterone / Q000097:blood / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012039:Regional Blood Flow / Q000187:drug effects; D015430:Weight Gain / Q000187:drug effects
D011374:Progesterone