Studies on LHRBI of sheep corpora lutea--a preliminary report on in vivo administration to rhesus monkeys.
An LH-receptor binding inhibitor (LHRBI), previously isolated from sheep corpora lutea in a partially purified form was subjected to wheat germ lectin chromatography. The unadsorbed fraction (UM-2R-III A) thus obtained had maximum LHRBI activity. This preparation was utilized to develop polyclonal antibodies. The purified fraction could be radioiodinated, suggesting its peptide nature. Intravenous injections of UM-2R-IIIA at 200 microg protein per dose in two doses per day at 9.30 h and 16.30 h on days 1 and 2 of the menstrual cycle to regularly cycling monkeys resulted in a shortening of the length of the cycle by 2 to 3 days. In addition, serum levels of progesterone increased prior to ovulation and remained high through the cycle of all three treated monkeys. It is possible that LHRBI induced enhanced synthesis and/or secretion of progesterone by the ovarian follicles thus suggesting a role for LHRBI in ovarian function.
Dhir
Ravindra N
RN
Department of Reproductive Biomedicine, National Institute of Health and Family Welfare, New Delhi, India. dhir2@vet.upenn.edu
Kumari
G L
GL
D000818:Animals; D003338:Corpus Luteum; D005260:Female; D007275:Injections, Intravenous; D036341:Intercellular Signaling Peptides and Proteins; D008253:Macaca mulatta; D008597:Menstrual Cycle / Q000187:drug effects; D010053:Ovary / Q000502:physiology; D010455:Peptides / Q000008:administration & dosage* / Q000302:isolation & purification; D011374:Progesterone / Q000097:blood; D012756:Sheep
D036341:Intercellular Signaling Peptides and Proteins; C011898:LH receptor binding inhibitor; D010455:Peptides; D011374:Progesterone