Cellular physiology of retinal and choroidal arteriolar smooth muscle cells.

Norman Scholfield, Graham McGeown, Timothy Curtis

Research output: Contribution to journalArticlepeer-review

26 Citations (Scopus)

Abstract

Control of ocular blood flow occurs predominantly at the level of the retinal and choroidal arterioles. The present article provides an overview of the Ca2 + handling mechanisms and plasmalemmal ion channels involved in the regulation of retinal and choroidal arteriolar smooth muscle tone. Increases in global intracellular free Ca2 + ([Ca2 +]i) involve multiple mechanisms, including agonist-dependent release of Ca2 + from intracellular stores through activation of the inositol trisphosphate (IP3) pathway. Ca2 + enters by voltage-dependent L-type Ca2 + channels and novel dihydropyridine-sensitive store-operated nonselective cation channels. Ca2 + extrusion is mediated by plasmalemmal Ca2 +-ATPases and through Na+/Ca2+ exchange. Local Ca2 + transients (Ca2 + sparks) play an important excitatory role, acting as the building blocks for more global Ca2 + signals that can initiate vasoconstriction. K+ and Cl- channels may also affect cell function by modulating membrane potential. The precise contribution of each of these mechanisms to the regulation of retinal and choroidal perfusion in vivo warrants future investigation.
Original languageEnglish
Pages (from-to)11-24
Number of pages14
JournalMicrocirculation (New York, N.Y. : 1994)
Volume14
Issue number1
DOIs
Publication statusPublished - Jan 2007

ASJC Scopus subject areas

  • Genetics
  • Physiology
  • Cardiology and Cardiovascular Medicine

Fingerprint Dive into the research topics of 'Cellular physiology of retinal and choroidal arteriolar smooth muscle cells.'. Together they form a unique fingerprint.

Cite this