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Updated: Jun 25, 2026
08:44
The Utility of Stage-specific Mid-to-late Drosophila Follicle Isolation
Published on: December 3, 2013
Follicle selection in monovular species
O J Ginther1, M A Beg, D R Bergfelt
1Department of Animal Health and Biomedical Sciences, University of Wisconsin, 1656 Linden Drive, Madison, WI 53706, USA. ojg@ahabs.wisc.edu
Biology of Reproduction
|August 22, 2001
Summary
Follicle deviation, a key event in selecting a dominant follicle, is driven by a follicle-coupling mechanism. This process involves follicle-stimulating hormone (FSH) and luteinizing hormone (LH) interactions, ensuring only the largest follicle matures.
Area of Science:
- Reproductive Biology
- Endocrinology
- Veterinary Science
Background:
- Follicle selection is crucial for reproduction in monovular species.
- The deviation phase, where one follicle becomes dominant, is critical.
- Existing hypotheses suggest a complex interplay of hormones and follicle development.
Purpose of the Study:
- To elucidate the mechanism of follicle selection in cattle, focusing on the deviation phase.
- To investigate the role of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in dominant follicle selection.
- To understand the hormonal and cellular events leading to the establishment of follicular dominance.
Main Methods:
- Analysis of follicle diameters and hormonal profiles (FSH, inhibin, estradiol) during the deviation period.
- Investigation of luteinizing hormone (LH) surge characteristics and LH receptor presence in granulosa cells.
- Correlation of intrafollicular factors (estradiol, insulin-like growth factor-1) with FSH responsiveness.
Main Results:
- Follicle deviation in cattle is established within 8 hours, initiated by the largest follicle's dominance.
- An FSH:follicle-coupling hypothesis is supported, involving FSH decline modulated by inhibin and estradiol.
- LH surge and LH receptor appearance precede deviation, with LH stimulating estradiol and IGF-1 production in the dominant follicle.
Conclusions:
- Follicle selection is established through a dynamic hormonal interplay, primarily involving FSH and LH.
- The dominant follicle's advanced development allows it to utilize low FSH concentrations, while smaller follicles become susceptible.
- This mechanism ensures the selection of a single dominant follicle capable of ovulation.
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