Effects of Gonadotropic Hormones on Rat Ovarian Lysosomes

• Published in: Biology of reproduction Vol. 8; no. 5; pp. 523 - 530
• Main Authors: Dimino, M J, Reece, R P
• Format: Journal Article
• Language: English
• Published: United States Society for the Study of Reproduction 01.06.1973
• Subjects: Acid Phosphatase - metabolism; Animals; Cathepsins - metabolism; Chorionic Gonadotropin - pharmacology; Clinical Enzyme Tests; Female; Follicle Stimulating Hormone - pharmacology; Glucuronidase - metabolism; Gonadotropins, Pituitary - pharmacology; Hydrolases - analysis; Luteinizing Hormone - pharmacology; Lysosomes - drug effects; Ovary - enzymology; Ovulation - drug effects; Rats; Ribonucleases - metabolism
• ISSN: 0006-3363; 1529-7268
• DOI: 10.1093/biolreprod/8.5.523

Changes in lysosomal hydrolases (cathepsin, β-glucuronidase, acid phosphatase, and acid ribonuclease) were studied in ovaries of gonadotropic treated immature rats. As compared to nontreated controls, ovaries of PMSG-treated rats (20 IU of PMSG, killed 54 h later) decreased in their percent nonsedimentable acid hydrolase activities (i.e., the enzyme activities remaining in the supernatant after sedimenting ovarian homogenates at 31,000 g x 120 min). Ovaries from PMSG-HCG-treated rats (20 IU of PMSG, 40 IU of HCG 54 h later, and killed 16 h after HCG injection) increased in their percent nonsedimentable hydrolase activities over the PMSG-treatment values. Free hydrolase activities (i.e., the nonsedimentable activities plus that part of the sedimentable activities accessible to the enzyme assay systems) without Triton X-100 treatment were determined by introducing homogenates containing intact lysosomes directly into the enzyme assay systems. With PMSG treatment, all acid hydrolases, except acid phosphatase, decreased from control levels in percent free activities. With PMSG-HCG treatment, only cathepsin increased over the PMSG treatment value. In vitro incubations of isolated ovarian lysosomes with gonadotropins showed that PMSG decreased acid phosphatase and acid ribonuclease release, FSH had no effect, HCG increased cathepsin release, and LH increased cathepsin,β -glucuronidase, and acid ribonuclease release but decreased acid phosphatase release. These changes in lysosomal enzymes with gonadotropic treatments are discussed in terms of follicular growth and ovulation.