| Differential effects of diet-induced obesity on BKCa {beta}1-subunit expression and function in rat skeletal muscle arterioles and small cerebral arteries. | |
| | |
MedLine Citation:
|
PMID: 21536854 Owner: NLM Status: Publisher |
Abstract/OtherAbstract:
|
Mechanisms underlying obesity-related vascular dysfunction are unclear. This study examined the effect of diet-induced obesity on expression and function of large conductance Ca(2+)-activated potassium channel (BK(Ca)) in rat pressurized small resistance vessels with myogenic tone. Male Sprague-Dawley rats fed a cafeteria-style high fat diet (HFD; ~30% energy from fat) for 16-20 weeks were ~30% heavier than controls fed standard chow (~13% fat). Obesity did not alter BK(Ca) α-subunit function, or α-subunit protein or mRNA expression in vessels isolated from the cremaster muscle or middle-cerebral circulations. In contrast, BKCa β(1)-subunit protein expression and function were significantly reduced in cremaster muscle arterioles, but increased in middle-cerebral arteries from obese animals. Immunohistochemistry showed α- and β(1)-subunits were present exclusively in the smooth muscle of both vessels. Cremaster muscle arterioles from obese animals showed significantly increased medial thickness, media-to-lumen ratio and pressurized arterioles showed increased myogenic tone at 30mmHg, but not 50-120 mmHg. Myogenic tone was not affected by obesity in middle-cerebral arteries. The BK(Ca) antagonist iberiotoxin constricted both cremaster muscle and mid cerebral arteries from control rats; this effect of iberiotoxin was abolished in cremaster muscle arteries only from obese rats. Diet-induced obesity has contrasting effects on BKCa function in different vascular beds, through differential effects on β(1)-subunit expression. However, these alterations in BK(Ca) function had little effect on overall myogenic tone, suggesting that the mechanisms controlling overall myogenic tone can be altered and compensate for altered BK(Ca) expression and function. |
| | |
Authors:
|
Lauren Howitt; Shaun L Sandow; T Hilton Grayson; Zoe E Ellis; Margaret J Morris; Timothy V Murphy |
Related Documents
:
|
18991244 - Biochemical effects of consumption of eggs containing omega-3 polyunsaturated fatty acids. 951384 - The effect of the duration of starvation of the assay bird on true metabolizable energy... 21058064 - Effects of enterococcus faecium m 74 strain on selected blood and production parameters... 11495474 - Effects of dietary 1, 4-diaminobutane (putrescine) on eggshell quality and laying perfo... 9696414 - Potentiated beta-cell response to non-glucose stimuli in insulin-resistant c57bl/6j mice. 6707294 - Milk composition and yield of the black bedouin goat during dehydration and rehydration. |
Publication Detail:
|
Type: JOURNAL ARTICLE Date: 2011-5-2 |
Journal Detail:
|
Title: American journal of physiology. Heart and circulatory physiology Volume: - ISSN: 1522-1539 ISO Abbreviation: - Publication Date: 2011 May |
Date Detail:
|
Created Date: 2011-5-3 Completed Date: - Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 100901228 Medline TA: Am J Physiol Heart Circ Physiol Country: - |
Other Details:
|
Languages: ENG Pagination: - Citation Subset: - |
Affiliation:
|
1. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
|
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: sGC{alpha}1 mediates the negative inotropic effects of NO in cardiac myocytes independent of changes...
Next Document: Comparative Effects of Nesiritide and Nitroglycerin on Renal Function, and Incidence of Renal Injury...