A Role for the alpha1-Adrenergic Signalling Pathway in the Response of Papillary Muscles from Type 2 Diabetic Hearts to Anoxia-Reoxygenation

Authors: Barbara Huisamen1; Jeanne Upton2; Amanda Lochner2

Source: Cardiovascular Drugs and Therapy, Volume 18, Number 4, July 2004 , pp. 247-255(9)

Publisher: Springer

Key:
Free Content - Free Content
New Content - New Content
Subscribed Content - Subscribed Content
Free Trial Content - Free Trial Content

Abstract:

Hearts from animal models of type 2 diabetes present with abnormal contractility patterns. The role of altered alpha1-adrenergic signalling in this is not understood. In this study we report overexpression and altered regulation of alpha1-adrenergic receptors in two models of type 2 diabetic rat hearts. In combination with reduced contractile performance, papillary muscles from these hearts presented with an enhanced ability to react to alpha1-adrenergic stimulation. Concurrently, these muscles were protected against anoxia/reoxygenation induced damage. This protection could be abolished by pretreatment with the alpha1-adrenergic antagonist, prazosin. Overexpression of alpha1-adrenergic receptors may therefore be a two-edged sword: supplying a contractile reserve that can protect against anoxia/reoxygenation induced effects on inotropic ability on the one hand but also predisposing the hearts to elevated induction of intracellular Ca2+ release and possible arrhythmic effects on the other hand.

Keywords: alpha-adrenergic signalling; type 2 diabetes; myocardium; anoxia/reoxygenation; papillary muscle

Document Type: Research article

DOI: 10.1023/B:CARD.0000041244.50971.ae

Affiliations: 1: MRC Diabetes & Heart Research Group, Department of Medical Physiology and Biochemistry, Faculty of Health Sciences, University of Stellenbosch, P.O. Box 19063, Tygerberg 7505, Republic of South Africa., Email: bh3@sun.ac.za 2: MRC Diabetes & Heart Research Group, Department of Medical Physiology and Biochemistry, Faculty of Health Sciences, University of Stellenbosch, P.O. Box 19063, Tygerberg 7505, Republic of South Africa

The full text electronic article is available for purchase. You will be able to download the full text electronic article after payment.

$47.00 plus tax      Refund Policy

 

OR

Back to top

Key:
Free Content - Free Content
New Content - New Content
Subscribed Content - Subscribed Content
Free Trial Content - Free Trial Content
Share this item with others: These icons link to social bookmarking sites where readers can share and discover new web pages.
Page Help Click here for Page Help
Shopping cart
Tools
Sign in






Need to register?
Sign up here
Text size: A | A | A | A