DISSOCIATION BETWEEN LH-INDUCED AEROBIC GLYCOLYSIS AND OOCYTE MATURATION IN CULTURED GRAAFIAN FOLLICLES OF THE RAT

1976 ◽  
Vol 81 (2) ◽  
pp. 362-366 ◽  
Author(s):  
A. Tsafriri ◽  
M. E. Lieberman ◽  
K. Ahrén ◽  
H. R. Lindner
Keyword(s):  
Energy Source ◽  
Luteinizing Hormone ◽  
Oocyte Maturation ◽  
Aerobic Glycolysis ◽  
Follicle Cells ◽  
Meiotic Arrest ◽  
Lactate Accumulation ◽  
Glycolytic Activity ◽  
Stimulation Of

ABSTRACT Luteinizing hormone (NIH-LH-S18; 5 μg/ml) stimulated aerobic glycolysis in cultured Graafian follicles explanted from pro-oestrous rats before the preovulatory gonadotrophin surge: lactate accumulation in the medium was 70 % above control levels during 6 h incubations. Iodoacetate (2.5× 10-5 m) prevented this effect, without impairing the ability of LH to induce resumption of oocytic meiosis. Enrichment of the medium with pyruvate (3.3 × 10-4 m) or lactate (2.5 × 10-2 m) did not in itself cause ovum maturation. The results do not support the hypothesis that termination of meiotic arrest by LH is due to stimulation of glycolytic activity in the follicle cells, resulting in increased availability of an energy source readily utilizable by the oocyte.

scholarly journals Stops and starts in mammalian oocytes: recent advances in understanding the regulation of meiotic arrest and oocyte maturation

Reproduction ◽  
2005 ◽  
Vol 130 (6) ◽  
pp. 791-799 ◽  
Author(s):  
Lisa M Mehlmann
Keyword(s):  
G Protein ◽  
Oocyte Maturation ◽  
Cumulus Cells ◽  
Follicle Cells ◽  
Meiotic Maturation ◽  
Meiotic Arrest ◽  
Epidermal Growth ◽  
High Level ◽  
G Protein Coupled ◽  
Stimulation Of

Mammalian oocytes grow and undergo meiosis within ovarian follicles. Oocytes are arrested at the first meiotic prophase, held in meiotic arrest by the surrounding follicle cells until a surge of LH from the pituitary stimulates the immature oocyte to resume meiosis. Meiotic arrest depends on a high level of cAMP within the oocyte. This cAMP is generated by the oocyte, through the stimulation of the GsG-protein by the G-protein-coupled receptor, GPR3. Stimulation of meiotic maturation by LH occurs via its action on the surrounding somatic cells rather than on the oocyte itself. LH induces the expression of epidermal growth factor-like proteins in the mural granulosa cells that act on the cumulus cells to trigger oocyte maturation. The signaling pathway between the cumulus cells and the oocyte, however, remains unknown. This review focuses on recent studies highlighting the importance of the oocyte in producing cAMP to maintain arrest, and discusses possible targets at the level of the oocyte on which LH could act to stimulate meiotic resumption.

OOCYTIC MEIOSIS IN CULTURED RAT FOLLICLES DURING INHIBITION OF STEROIDOGENESIS

1976 ◽  
Vol 83 (1) ◽  
pp. 151-157 ◽  
Author(s):  
M. E. Lieberman ◽  
A. Tsafriri ◽  
S. Bauminger ◽  
W. P. Collins ◽  
K. Ahrén ◽  
...  
Keyword(s):  
Luteinizing Hormone ◽  
Oocyte Maturation ◽  
Prostaglandin E ◽  
Steroid Secretion

ABSTRACT Steroid release by cultured Graafian follicles explanted from rat ovaries on the morning of pro-oestrus was measured by radioimmunoassay. Addition of cyanoketone (10−4m) or aminoglutethimide (10−3m) to the medium reduced the basal level of steroid secretion (progesterone, androstenedione and oestradiol-17β) and abolished the steroidogenic effects of luteinizing hormone (LH; 5μg/ml) and prostaglandin E2 (PGE2; 10 μg/ml). However, the induction of oocyte maturation by either LH or PGE2 was not impaired by total suppression of the steroidogenic response of the follicles to these hormones by cyanoketone or aminoglutethimide. It is concluded that the meiosis-inducing action of LH on the mammalian egg is not mediated by the effect of the hormone on the rate and pattern of follicular steroidogenesis.

Zinc mediates the action of androgen in acting as a downstream effector of luteinizing hormone on oocyte maturation in zebrafish†

2018 ◽  
Vol 100 (2) ◽  
pp. 468-478 ◽  
Author(s):  
Jianzhen Li ◽  
Duo Huang ◽  
Xiao Sun ◽  
Xuehui Li ◽  
Christopher H K Cheng
Keyword(s):  
Luteinizing Hormone ◽  
Oocyte Maturation ◽  
Downstream Effector

scholarly journals Photoperiodic regulation of glutamatergic stimulation of secretion of luteinizing hormone in male Syrian hamsters

Reproduction ◽  
1992 ◽  
Vol 95 (3) ◽  
pp. 935-946 ◽  
Author(s):  
Y. Hui ◽  
M. H. Hastings ◽  
E. S. Maywood ◽  
F. J. P. Ebling
Keyword(s):  
Luteinizing Hormone ◽  
Syrian Hamsters ◽  
Photoperiodic Regulation ◽  
Stimulation Of
Sign in / Sign up

Export Citation Format

Share Document