Importance of glutathione in the acquisition and maintenance of sperm nuclear decondensing activity in maturing hamster oocytes

• Published in: Developmental biology Vol. 125; no. 1; pp. 181 - 186
• Main Authors: Perreault, Sally D., Barbee, Randy R., Slott, Valerie L.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 1988; Elsevier
• Subjects: Animals; Biological and medical sciences; Buthionine Sulfoximine; Cricetinae; Disulfides - metabolism; Early stages. Segmentation. Gastrulation. Neurulation; Embryology: invertebrates and vertebrates. Teratology; Female; Fundamental and applied biological sciences. Psychology; Glutathione - physiology; Male; Mesocricetus; Methionine Sulfoximine - analogs & derivatives; Methionine Sulfoximine - pharmacology; Oocytes - drug effects; Oocytes - growth & development; Spermatozoa - metabolism; Zygote - analysis; Zygote - drug effects; Gamete; Vertebrata; Regulation(control); Mammalia; Rodentia; Fecundation; Hamster; Oocyte; Glutathione; Oocyte maturation
• ISSN: 0012-1606; 1095-564X
• DOI: 10.1016/0012-1606(88)90070-X

Sperm nuclear decondensing activity in mammalian oocytes is dependent upon the maturational state of the oocyte. It is maximal in mature, metaphase II oocytes and minimal or absent in immature germinal vesicle (GV) and fertilized pronuclear oocytes. Previous studies suggested that this difference may be due to the relative ability of an oocyte to reduce the protamine disulfide bonds in the sperm nucleus. The results of this study show that mature hamster oocytes contain significantly more glutathione (GSH), about 8 m
M, and hence more disulfide reducing power, as compared with GV (4 m
M) or pronuclear (6 m
M) oocytes. Furthermore, the acquisition of sperm nuclear decondensing activity by maturing oocytes can be prevented or delayed by blocking GSH synthesis with
l-buthionine-
S,R-sulfoximine during the early stages of oocyte maturation. This is the first evidence that modulation of GSH levels during oocyte maturation and fertilization may be a mechanism by which sperm nuclear decondensing activity is regulated.