Role of luteinizing hormone in luteotropic complex of pregnant hamster

Journal Article · Wed Apr 01 04:00:00 EST 1987 · Am. J. Physiol.; (United States)

OSTI ID:5767121

Tamura, H; Greenwald, G S

Hamsters were hypophysectomized on day 4 of pregnancy and injected subcutaneously on days 4-7 with various combinations of 200 ..mu..g prolactin (Prl), 10 ..mu..g follicle-stimulating hormone (FSH), and 20 ..mu..g luteinizing hormone (LH) in polyvinylpyrrolidone (PVP) to decrease its rate of absorption or in saline. End points for luteal function on day 8 were maintenance of pregnancy, serum progesterone (P/sub 4/), luteal weight, and luteal binding for human chorionic gonadotropin, FSH, and Prl. After hypophysectomy, a drastic decline occurred in all parameters including an 89% decrease in luteal weight. Injection of Prl did not maintain pregnancy nor serum P/sub 4/ but partially maintained luteal weight and human chorionic gonadotropin binding sites per corpus luteum. The minimal luteotropic complex of Prl and FSH was effective in maintaining pregnancy and significantly increased serum P/sub 4/ and Prl and FSH receptors but not to control levels. Thus, the luteotropic activity of LH was only demonstrable when it was injected in a long-acting form; when delivered as a bolus, LH (saline) was luteolytic. P/sub 4/ and estradiol were measured by radioimmunoassay. Radioiodinated gonadotropins were prepared. The percentage of tracer reacting with an excess of receptor were 51% of /sup 125/I-FSH and 45.9% of /sup 125/I-hCG using whole homogenates of hamster ovaries.

• Research Organization: Univ. of Kansas, Kansas City
• OSTI ID: 5767121
• Journal Information: Am. J. Physiol.; (United States), Journal Name: Am. J. Physiol.; (United States) Vol. 252:4; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ANIMALS
BETA DECAY RADIOISOTOPES
BODY
CELL CONSTITUENTS
CELL MEMBRANES
CONFIGURATION INTERACTION
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
ELECTRON CAPTURE RADIOISOTOPES
ESTRADIOL
ESTRANES
ESTROGENS
FEMALE GENITALS
FSH
GLANDS
GONADOTROPINS
GONADS
HAMSTERS
HORMONES
HYDROXY COMPOUNDS
IMMUNOASSAY
IMMUNOLOGY
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
KETONES
LABELLED COMPOUNDS
LH
LIVER
LTH
MAMMALS
MEMBRANES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANS
OVARIES
PEPTIDE HORMONES
PITUITARY HORMONES
PREGNANCY
PREGNANES
PROGESTERONE
RADIOASSAY
RADIOIMMUNOASSAY
RADIOIMMUNOLOGY
RADIOISOTOPES
RODENTS
STEROID HORMONES
STEROIDS
TRACER TECHNIQUES
VERTEBRATES