Cholesterol depletion disrupts caveolae and differentially impairs agonist-induced arterial contraction.
(2002) In Arteriosclerosis, Thrombosis and Vascular Biology 22(8). p.1267-1272- Abstract
- OBJECTIVE: This study assessed the role of cholesterol-rich membrane regions, including caveolae, in the regulation of arterial contractility. Methods and Results- Rat tail artery devoid of endothelium was treated with the cholesterol acceptor methyl-beta-cyclodextrin, and the effects on force and Ca2+ handling were evaluated. In cholesterol-depleted preparations, the force responses to alpha1-adrenergic receptors, membrane depolarization, inhibition of myosin light chain phosphatase, and activation of G proteins with a mixture of 20 mmol/L NaF and 60 micro mol/L AlCl3 were unaffected. In contrast, responses to 5-hydroxytryptamine (5-HT), vasopressin, and endothelin were reduced by >50%. The rise in global intracellular free Ca2+... (More)
- OBJECTIVE: This study assessed the role of cholesterol-rich membrane regions, including caveolae, in the regulation of arterial contractility. Methods and Results- Rat tail artery devoid of endothelium was treated with the cholesterol acceptor methyl-beta-cyclodextrin, and the effects on force and Ca2+ handling were evaluated. In cholesterol-depleted preparations, the force responses to alpha1-adrenergic receptors, membrane depolarization, inhibition of myosin light chain phosphatase, and activation of G proteins with a mixture of 20 mmol/L NaF and 60 micro mol/L AlCl3 were unaffected. In contrast, responses to 5-hydroxytryptamine (5-HT), vasopressin, and endothelin were reduced by >50%. The rise in global intracellular free Ca2+ concentration in response to 5-HT was attenuated, as was the generation of Ca2+ waves at the cellular level. By electron microscopy, cholesterol depletion was found to disrupt caveolae. The 5-HT response could be restored by exogenous cholesterol, which also restored caveolae. Western blots showed that the levels of 5-HT2A receptor and of caveolin-1 were unaffected by cholesterol extraction. Sucrose gradient centrifugation showed enrichment of 5-HT2A receptors, but not alpha1-adrenergic receptors, in the caveolin-1-containing fractions, suggesting localization of the former to caveolae. CONCLUSIONS: These results show that a subset of signaling pathways that regulate smooth muscle contraction depends specifically on cholesterol. Furthermore, the cholesterol-dependent step in serotonergic signaling occurs early in the pathway and depends on the integrity of caveolae. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/109885
- author
- Dreja, Karl LU ; Voldstedlund, Marianne ; Vinten, Jørgen ; Tranum-Jensen, Jørgen ; Hellstrand, Per LU and Swärd, Karl LU
- organization
- publishing date
- 2002
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- 5-hydroxytryptamine, intracellular calcium, endothelin, smooth muscle, caveolae
- in
- Arteriosclerosis, Thrombosis and Vascular Biology
- volume
- 22
- issue
- 8
- pages
- 1267 - 1272
- publisher
- Lippincott Williams & Wilkins
- external identifiers
-
- pmid:12171786
- wos:000177530500007
- scopus:0036344517
- ISSN
- 1524-4636
- DOI
- 10.1161/01.ATV.0000023438.32585.A1
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Department of Experimental Medical Science (013210000), Unit on Vascular Diabetic Complications (013241510), Vascular Physiology (013212034)
- id
- c7502464-e7e1-405c-831f-f2f68b018db6 (old id 109885)
- date added to LUP
- 2016-04-01 11:50:28
- date last changed
- 2022-05-14 05:48:11
@article{c7502464-e7e1-405c-831f-f2f68b018db6,
abstract = {{OBJECTIVE: This study assessed the role of cholesterol-rich membrane regions, including caveolae, in the regulation of arterial contractility. Methods and Results- Rat tail artery devoid of endothelium was treated with the cholesterol acceptor methyl-beta-cyclodextrin, and the effects on force and Ca2+ handling were evaluated. In cholesterol-depleted preparations, the force responses to alpha1-adrenergic receptors, membrane depolarization, inhibition of myosin light chain phosphatase, and activation of G proteins with a mixture of 20 mmol/L NaF and 60 micro mol/L AlCl3 were unaffected. In contrast, responses to 5-hydroxytryptamine (5-HT), vasopressin, and endothelin were reduced by >50%. The rise in global intracellular free Ca2+ concentration in response to 5-HT was attenuated, as was the generation of Ca2+ waves at the cellular level. By electron microscopy, cholesterol depletion was found to disrupt caveolae. The 5-HT response could be restored by exogenous cholesterol, which also restored caveolae. Western blots showed that the levels of 5-HT2A receptor and of caveolin-1 were unaffected by cholesterol extraction. Sucrose gradient centrifugation showed enrichment of 5-HT2A receptors, but not alpha1-adrenergic receptors, in the caveolin-1-containing fractions, suggesting localization of the former to caveolae. CONCLUSIONS: These results show that a subset of signaling pathways that regulate smooth muscle contraction depends specifically on cholesterol. Furthermore, the cholesterol-dependent step in serotonergic signaling occurs early in the pathway and depends on the integrity of caveolae.}},
author = {{Dreja, Karl and Voldstedlund, Marianne and Vinten, Jørgen and Tranum-Jensen, Jørgen and Hellstrand, Per and Swärd, Karl}},
issn = {{1524-4636}},
keywords = {{5-hydroxytryptamine; intracellular calcium; endothelin; smooth muscle; caveolae}},
language = {{eng}},
number = {{8}},
pages = {{1267--1272}},
publisher = {{Lippincott Williams & Wilkins}},
series = {{Arteriosclerosis, Thrombosis and Vascular Biology}},
title = {{Cholesterol depletion disrupts caveolae and differentially impairs agonist-induced arterial contraction.}},
url = {{http://dx.doi.org/10.1161/01.ATV.0000023438.32585.A1}},
doi = {{10.1161/01.ATV.0000023438.32585.A1}},
volume = {{22}},
year = {{2002}},
}