Biol Reprod Keystone Symposia Conference on Frontiers in Reproductive Biology & Regulation of Fertility.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by DILLS, W. L.
Right arrow Articles by ONUMA, E. K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by DILLS, W. L., JR.
Right arrow Articles by ONUMA, E. K.
Agricola
Right arrow Articles by DILLS, W. L.
Right arrow Articles by ONUMA, E. K.

Biology of Reproduction, Vol 25, 458-465, Copyright © 1981 by Society for the Study of Reproduction

Inhibitory Effects of Substrate Analogs on Lactate Production from Fructose and Glucose in Bovine Spermatozoa

WILLIAM L. DILLS JR. 1, LINDA SCHAFFER BELL 1, , and EDWARD K. ONUMA 1

1 Division of Nutritional Sciences and Section of Biochemistry, Cell and Molecular Biology, Division of Biological Sciences, Cornell University, Ithaca, New York 14853


A number of substrate analogs were tested as inhibitors of bovine sperm lactate formation from glucose and from fructose. When 1 mM glucose was the substrate, lactate production was inhibited by 5-thioglucose, 2-deoxyglucose, 2,5-anhydromannitol, and 5-ketofructose while no inhibition was observed with 1-deoxyfructose, 4,6-ethylideneglucose, N-acetylglucosamine, or 3-0 methylglucose at concentrations up to 10 mM. 5-Thioglucose was most effective, producing complete inhibition at a 10 mM concentration. Inhibition by the other inhibitory analogs was not complete at 10 mM. All of the observed inhibitions could be overcome by increasing glucose concentration to 10 mM.

When 10 mM fructose was used as a substrate, lactate production was inhibited by 5-thioglucose, 2-deoxyglucose, 2,5-anhydromannitol, 5-ketofructose, and 4,6-ethylideneglucose while 1-deoxyfructose, 3-0-methylglucose, and N-acetylglucosamine were not inhibitory. Complete inhibition could be produced by either 2 mM 5-thioglucose or 3 mM 2-deoxyglucose. Inhibition by the other three analogs was only partial at analog concentrations of 10 mM. Except for the inhibition produced by 4,6-ethylideneglucose, all of the inhibitions could be overcome in full or in part by increasing fructose concentrations to 100 mM.

The inhibitory patterns observed with most of the analogs are consistent with the involvement of a hexokinase phosphorylation step. 2-Deoxyglucose, a good hexokinase substrate, was a strong inhibitor; 2,5-anhydromannitol and 5-ketofructose, which are less effective hexokinase substrates, were partial inhibitors, and 1-deoxyfructose, which is a poor substrate, and 3-0-methylglucose and N-acetylglucosamine, which are not substrates, were not inhibitory. 5-Thioglucose and 4,6-ethylideneglucose do not inhibit in a manner consistent with their previously observed interactions with either uptake systems or with hexokinases.

Note:
ACKNOWLEDGMENTS We wish to thank Drs. Robert Foote and Robert Wall of the Dept. of Animal Sciences, Cornell University, and Dr. Peter Kingsley of the Division of Nutritional Sciences, Cornell University, for helpful discussions. Drs. Foote and Wall also assisted in the arrangements for the supply of bovine spermatozoa from Eastern Artificial Insemination Co-op. Dr. Wall’s assistance with spermatozoan methodology in early parts of this study was particularly helpful. The technical assistance of Gerry McDonough and Tom Covey is gratefully acknowledged.

Submitted on December 17, 1980
Accepted on May 6, 1981






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1981 by the Society for the Study of Reproduction.