Header

UZH-Logo

Maintenance Infos

Tolerance of spermatozoa to hypotonic stress: role of membrane fluidity and correlation with cryosurvival


Oldenhof, Harriëtte; Heutelbeck, Anna; Blässe, Anne-Kathrin; Bollwein, Heinrich; Martinsson, Gunilla; Wolkers, Willem F; Sieme, Harald (2015). Tolerance of spermatozoa to hypotonic stress: role of membrane fluidity and correlation with cryosurvival. Reproduction, Fertility and Development, 27(2):285-93.

Abstract

The aim of this study was to evaluate inter-individual variability in osmotic properties of stallion spermatozoa and its correlation with cryosurvival. In addition, temperature dependency of hypo-osmotic tolerance and membrane fluidity were studied. Stallion sperm membranes exhibited good resistance towards hypotonic stress in the 15-30 °C temperature range, whereas membrane stability was found to be decreased at 4 and 37 °C. Bull spermatozoa showed greater hypo-osmotic tolerance compared with stallion spermatozoa, especially at temperatures above 30 °C, which coincided with decreased membrane fluidity of bovine spermatozoa in this temperature range. The critical osmolality at 22 °C, at which half of the sperm population survived exposure to hypotonic saline solution, was found to vary between 55 and 170 mOsm kg(-1) among different stallions. Clear correlations were found for pre- versus post-freeze sperm motility and membrane integrity. Pre-freeze percentages of membrane-intact spermatozoa after exposure to hypotonic stress showed a weak correlation with sperm motility after cryopreservation. This correlation, however, was not found when data were corrected for initial numbers of membrane-intact spermatozoa in the sample. We thus conclude that studies on pre-freeze tolerance towards hypotonic stress cannot be used to predict sperm cryosurvival rates for individual stallions.

Abstract

The aim of this study was to evaluate inter-individual variability in osmotic properties of stallion spermatozoa and its correlation with cryosurvival. In addition, temperature dependency of hypo-osmotic tolerance and membrane fluidity were studied. Stallion sperm membranes exhibited good resistance towards hypotonic stress in the 15-30 °C temperature range, whereas membrane stability was found to be decreased at 4 and 37 °C. Bull spermatozoa showed greater hypo-osmotic tolerance compared with stallion spermatozoa, especially at temperatures above 30 °C, which coincided with decreased membrane fluidity of bovine spermatozoa in this temperature range. The critical osmolality at 22 °C, at which half of the sperm population survived exposure to hypotonic saline solution, was found to vary between 55 and 170 mOsm kg(-1) among different stallions. Clear correlations were found for pre- versus post-freeze sperm motility and membrane integrity. Pre-freeze percentages of membrane-intact spermatozoa after exposure to hypotonic stress showed a weak correlation with sperm motility after cryopreservation. This correlation, however, was not found when data were corrected for initial numbers of membrane-intact spermatozoa in the sample. We thus conclude that studies on pre-freeze tolerance towards hypotonic stress cannot be used to predict sperm cryosurvival rates for individual stallions.

Statistics

Citations

5 citations in Web of Science®
6 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

0 downloads since deposited on 16 Feb 2016
0 downloads since 12 months

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:05 Vetsuisse Faculty > Veterinary Clinic > Department of Farm Animals
Dewey Decimal Classification:570 Life sciences; biology
630 Agriculture
Language:English
Date:January 2015
Deposited On:16 Feb 2016 11:01
Last Modified:08 Dec 2017 18:11
Publisher:C S I R O Publishing
ISSN:1031-3613
Publisher DOI:https://doi.org/10.1071/RD13177
PubMed ID:25482034

Download