[Magnesium ions and contractile activity of vascular smooth muscle cells in hypoxia].
In isolated smooth muscle of the rat portal vein removal of Mg2+ from perfusate induced rapid enhancement of frequency and amplitude of spontaneous contractions and decreased inhibiting effect of hypoxia on the smooth muscle contractile activity. Concomitant elevation of extracellular Ca2+ has no additional protective effect on the smooth muscle in hypoxia. Ten-fold lowering of Mg2+ content in buffer solution resulted in a significant rise in the tension of the smooth muscle activated by Ca2+. The data obtained suggest that protective effect of Mg2+-free solution on vascular smooth muscle in hypoxia may be mediated not only through increases intracellular Ca2+ concentration but also due to rising sensitivity of the smooth muscle cells contractile protein to Ca2+.
Bershteĭn
S A
SA
Solov'ev
A I
AI
Stepanenko
L G
LG
Baziliuk
O V
OV
D000818:Animals; D066298:In Vitro Techniques; D008274:Magnesium / Q000502:physiology*; D009119:Muscle Contraction; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000503:physiopathology*; D010100:Oxygen / Q000494:pharmacology*; D051381:Rats
D008274:Magnesium; D010100:Oxygen
Iony magniia i sokratitel'naia aktivnost' gladkomyshechnykh kletok sosudov pri gipooksigenatsii.