Altered ovarian responsiveness to gonadotropins in neonatally irradiated immature rats

Journal Article · Fri Jan 01 00:00:00 EST 1988 · Endocr. Res.; (United States)

DOI:https://doi.org/10.1080/07435808809036338· OSTI ID:6895918

Freud, A; Sod-Moriah, U A

Female rats which were exposed to a single low dose of gamma irradiation (6R or 15R) at the age of 8 days produce smaller litters when mature than untreated controls. In order to study the possibility that such an impaired reproductive performance could result from a reduced ovulation rate, neonatally irradiated females were treated with PMSG (12 iu/rat) at the age of 26 days. Another group of rats, similarly treated, was further injected with hCG (5 iu/rat) 48 hours later. Animals were killed 48, 55, 60 and 72 hours after PMSG treatment or 72 and 120 after hCG injection. The results indicated that PMSG treatment increased the ovarian weight of non-irradiated controls as well as of irradiated rats and in all animals induced a proestrus like profile of LH. Only a combined treatment of PMSG and hCG resulted in ovulation and corpora lutea formation with significantly increased numbers of corpora lutea in the ovaries of the irradiated rats. The latter was associated with higher progesterone plasma levels not correlated to the number of corpora lutea. The gradual decrease in the number of ovarian binding sites for hCG with increased radiation dose and the increased association constant in the 15R group could not explain the increased sensitivity of the ovary to exogenous gonadotropins which results from neonatal exposure to low doses of gamma irradiation.

• Research Organization: Nuclear Research Center-Negev, Beer Sheva (Israel)
• OSTI ID: 6895918
• Journal Information: Endocr. Res.; (United States), Vol. 14:1
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
GONADOTROPINS
RADIOSENSITIVITY EFFECTS
NEONATES
RADIOSENSITIVITY
OVARIES
BIOLOGICAL RADIATION EFFECTS
ACUTE IRRADIATION
ESTRADIOL
GAMMA RADIATION
LH
OVULATION
PROGESTERONE
RADIATION DOSES
RATS
TESTOSTERONE
ACUTE EXPOSURE
ANDROGENS
ANDROSTANES
ANIMALS
BIOLOGICAL EFFECTS
BODY
DOSES
ELECTROMAGNETIC RADIATION
ESTRANES
ESTROGENS
FEMALE GENITALS
GONADS
HORMONES
HYDROXY COMPOUNDS
IONIZING RADIATIONS
IRRADIATION
KETONES
MAMMALS
ORGANIC COMPOUNDS
ORGANS
PEPTIDE HORMONES
PITUITARY HORMONES
PREGNANES
RADIATION EFFECTS
RADIATIONS
RODENTS
STEROID HORMONES
STEROIDS
VERTEBRATES
560151* - Radiation Effects on Animals- Man