Science Links Japan | Effects of combined increase in [H+] and [ADP] on resting tension and Ca2+ sensitivity of contraction in membrane permeabilized cerebral artery.

Effects of combined increase in [H+] and [ADP] on resting tension and Ca2+ sensitivity of contraction in membrane permeabilized cerebral artery.

Accession number;01A0901052

Title;Effects of combined increase in [H+] and [ADP] on resting tension and Ca2+ sensitivity of contraction in membrane permeabilized cerebral artery.

Author; MORIMOTO S (Kyushu Univ., Fukuoka, Jpn) OHNUKI A (Juntendo School Medicine, Tokyo, Jpn)

Journal Title;Biomed Res

Journal Code:Z0236B

ISSN:0388-6107

VOL.22;NO.2;PAGE.111-114(2001)

Figure&Table&Reference;FIG.3, REF.17

Pub. Country;Japan

Language;English

Abstract;Accumulation of H+ and ADP in cytoplasm plays an important role in modifying the cellular functions under pathological conditions such as hypoxia. Cerebral vasospasm is a major cause of death and disability after subarachnoid hemorrhage (SAH), of which pathogenesis, nevertheless, is poorly understood. Using .BETA.-escin-permeabilized basilar artery that enabled us to control the intracellular solute composition under near-physiological conditions, we studied the possible involvement of increased intracellular H+ ([H+]i) and ADP ([ADP]i) in the pathogenesis of cerebral vasospasm. It was found that combined increase in [H+] and [ADP] led to an increase in the resting tension and a subsequent irreversible increase in the Ca2+ sensitivity of contraction accompanying a high level of phosphorylation in smooth muscle 20-kDa myosin light-chain (MLC20). The results suggest that intracellular metabolic inhibitions accompanying an increase in [H+]i and [ADP]i may play a role in the development of cerebral vasospasm after SAH through impairing the regulation of MLC20 Phosphorylation in arterial smooth muscle cells. (author abst.)

Related Articles;