Stage of the Estrous Cycle Does Not Influence Myocardial Ischemia–Reperfusion Injury in Rats (Rattus norvegicus)
Abstract:Even though cardiovascular disease is the leading cause of death for men and women, the vast majority of animal studies use male animals. Because female reproductive hormones have been associated with cardioprotective states, many investigators avoid using female animals because these hormones are cyclical and may introduce experimental variability. In addition, no studies have investigated the specific effects of the estrous cycle on cardiac ischemic injury. This study was conducted to determine whether the estrous cycle stage influences the susceptibility to ischemic injury in rat hearts. Estrous cycle stage was determined by using vaginal smear cytology, after which hearts underwent either in vivo (surgical) or ex vivo (isolated) ischemia–reperfusion injury. For in vivo studies, the left anterior coronary artery was ligated for 25 min of ischemia and subsequently released for 120 min of reperfusion. Infarct sizes were 42% ± 6%; 49% ± 4%; 40% ± 9%; 47% ± 9% of the zone-at-risk for rats in proestrus, estrus, metestrus, and diestrus, respectively. For ex vivo studies, isolated, perfused hearts underwent global ischemia and reperfusion for 25 and 120 min, respectively. Similar to our in vivo studies, the ex vivo rat model showed no significant differences in susceptibility to infarction or extent of cardiac arrhythmia according to estrous stage. To our knowledge, these studies provide the first direct evidence that the stage of estrous cycle does not significantly alter cardiac ischemia–reperfusion injury in rats.
Document Type: Research Article
Affiliations: 1: Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA 2: Department of Kinesiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA 3: Department of Comparative Medicine, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA. firstname.lastname@example.org
Publication date: 2013-10-01
Comparative Medicine (CM), an international journal of comparative and experimental medicine, is the leading English-language publication in the field and is ranked by the Science Citation Index in the upper third of all scientific journals. The mission of CM is to disseminate high-quality, peer-reviewed information that expands biomedical knowledge and promotes human and animal health through the study of laboratory animal disease, animal models of disease, and basic biologic mechanisms related to disease in people and animals.
Attention Members: To access the full text of the articles, be sure you are logged in to the AALAS website.
Attention: please note, due to a temporary technical problem, reference linking within the content is not available at this time
- Editorial Board
- Information for Authors
- Submit a Paper
- Subscribe to this Title
- Membership Information
- Information for Advertisers
- For issues prior to 1998
- Institutional Subscription Activation
- Ingenta Connect is not responsible for the content or availability of external websites