Linked Life Data

15709690

Source:http://linkedlifedata.com/resource/pubmed/id/15709690

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2005-2-15
pubmed:abstractText
Control of smooth muscle is vital for health. The major route to contraction is a rise in intracellular [Ca2+], determined by the entry and efflux of Ca2+ and release and re-uptake into the sarcoplasmic reticulum (SR). We review these processes in myometrium, to better understand excitation-contraction coupling and develop strategies for preventing problematic labours. The main mechanism of elevating [Ca2+] is voltage-gated L-type channels, due to pacemaker activity, which can be modulated by agonists. The rise of [Ca2+] produces Ca-calmodulin and activates MLCK. This phosphorylates myosin and force results. Without Ca2+ entry uterine contraction fails. The Na/Ca exchanger (NCX) and plasma membrane Ca-ATPase (PMCA) remove Ca2+, with contributions of 30% and 70% respectively. Studies with PMCA-4 knockout mice show that it contributes to reducing [Ca2+] and relaxation. The SR contributes to relaxation by vectorially releasing Ca2+ to the efflux pathways, and thereby increasing their rates. Agonists binding produces IP3 which can release Ca from the SR but inhibition of SR Ca2+ release increases contractions and Ca2+ transients. It is suggested that SR Ca2+ targets K+ channels on the surface membrane and thereby feedback to inhibit excitability and contraction.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0716-9760
pubmed:author
pubmed:issnType
Print
pubmed:volume
37
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
617-24
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Ca2+ entry, efflux and release in smooth muscle.
pubmed:affiliation
Department of Physiology, The University of Liverpool, Liverpool L69 3BX, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't