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Luteinizing hormone depletes ascorbic acid in preovulatory follicles
M M Guarnaccia1, M Takami, E E Jones
1Reproductive Biology Section, Yale University School of Medicine, New Haven, Connecticut 06520-8063, USA.
Fertility and Sterility
|November 1, 2000
Summary
Luteinizing hormone (LH) significantly depletes ascorbic acid in preovulatory follicles, with levels reduced by 40% within 2 hours. Oxygen radicals also contribute to this depletion, impacting follicular health.
Area of Science:
- Reproductive Biology
- Endocrinology
- Biochemistry
Background:
- Ascorbic acid is crucial for follicular development and oocyte quality.
- The role of luteinizing hormone (LH) in regulating follicular ascorbic acid levels remains unclear.
Purpose of the Study:
- To investigate the effect of LH on ascorbic acid levels in preovulatory follicles.
- To determine if LH-induced ovulation is associated with ascorbic acid depletion.
Main Methods:
- A controlled, prospective experimental study was conducted using Sprague-Dawley female rats.
- Follicular growth and ovulation were induced with gonadotropin treatment.
- Ascorbic acid levels in ovaries, follicles, and oocytes were analyzed using colorimetric analysis and high-pressure liquid chromatography.
Main Results:
- LH treatment maximally depleted ovarian ascorbic acid by 50% within 2 hours, sustained for 8 hours.
- Follicular ascorbic acid levels significantly decreased by 40% within 2 hours post-LH injection.
- Incubation with hCG or menadione reduced follicular ascorbic acid, while oocytes rapidly depleted it, enhanced by cumulus cells.
Conclusions:
- LH elevation and oxygen radical production are key factors in depleting preovulatory follicular ascorbic acid.
- This depletion may have implications for ovulation and oocyte quality.
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