Related Experiment Videos
Polyol pathway along the bovine epididymis
Gilles Frenette1, Carl Lessard, Robert Sullivan
1Centre de Recherche en Biologie de la Reproduction and Département d'Obstétrique-Gynécologie, Faculté de Médecine, Université Laval, Canada.
Molecular Reproduction and Development
|October 1, 2004
Summary
Male gametes gain fertilizing proteins via epididymosomes during epididymal transit. This study reveals aldose reductase and sorbitol dehydrogenase in the epididymis, suggesting the polyol pathway modulates sperm motility.
Area of Science:
- Reproductive biology
- Sperm physiology
- Biochemistry
Background:
- Spermatozoa acquire fertilizing ability during epididymal transit through protein transfer via epididymosomes.
- Aldose reductase (AKR1B5) is a major protein found on epididymosomes and in epididymal epithelial cells.
Purpose of the Study:
- To investigate the distribution and activity of aldose reductase and sorbitol dehydrogenase in the epididymis.
- To explore the potential role of the polyol pathway in sperm motility modulation.
Main Methods:
- Western and Northern blot analysis to determine enzyme and mRNA distribution.
- Enzyme activity assays at varying pH.
- Immunohistological studies to localize enzyme synthesis.
Main Results:
- Cytosolic aldose reductase activity and AKR1B5 mRNA were highest in proximal and middle epididymis segments, with optimal activity at pH 6.0-6.5.
- Sorbitol dehydrogenase and its mRNA were more abundant in proximal and distal segments.
- Both enzymes are synthesized by epididymal epithelial cells.
Conclusions:
- The polyol pathway, involving aldose reductase and sorbitol dehydrogenase, is present and active within the epididymis.
- The distribution patterns suggest a role for this pathway in regulating sperm motility during epididymal transit.