title: Estrogen attenuates HSP 72 expression in acutely exercised male rodents.
abstract: Estrogen has been shown to reduce post-exercise skeletal muscle damage. Exercise-induced muscle damage may be a factor in the elevated post-exercise expression of heat-shock proteins (HSPs). Thus, the present investigation was conducted in order to examine the influence of estrogen on post-exercise levels of HSP 72 and heat-shock cognate, HSC 73, in male and female rodents. Prior to an acute bout of treadmill running, male and female Sprague-Dawley rats received daily injections of either 40 microg x kg(-1) of beta-estradiol 3-benzoate or olive oil vehicle for 2 weeks. A two- to fourfold reduction in post-exercise HSP 72 content was observed in the heart, liver, lung and red and white vastus muscles of estradiol-treated males compared with their vehicle-injected counterparts (P < 0.05). Compared to the males, the females had significantly lower post-exercise HSP 72 levels which were not affected by estradiol supplementation. Moreover, estradiol administration in male rodents resulted in a HSP response similar to that of females following exercise. Thus, the results of the present investigation suggest that estrogen is the factor responsible for the observed differences in post-exercise HSP 72 levels between males and females.
authors.affiliation: School of Kinesiology, Faculty of Health Sciences, The University of Western Ontario, London, Canada.
authors.forename: Z
authors.initials: Z
authors.lastname: Paroo
authors.forename: P M
authors.initials: PM
authors.lastname: Tiidus
authors.forename: E G
authors.initials: EG
authors.lastname: Noble
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000187:drug effects* / Q000378:metabolism; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D050883:HSC70 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D050884:HSP72 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D010805:Physical Conditioning, Animal / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012737:Sex Factors
chemical_list: D002352:Carrier Proteins; D050883:HSC70 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D050884:HSP72 Heat-Shock Proteins; D006360:Heat-Shock Proteins; C494373:Hspa8 protein, rat; D004958:Estradiol