Vasoconstriction: a novel activity for low density lipoprotein.
Low density lipoprotein plays an important role in the pathogenesis of atherosclerosis. Cumulative addition of 1-30 micrograms/ml of LDL from normolipidemic subjects produced a dose-dependent increase in contractile tension of thoracic aortic rings from rats. The maximal LDL-induced contractile response was approximately 30% of that induced by 1 microM norepinephrine. Similar concentrations of LDL induced a dose-dependent transient increase of the concentration of intracellular free calcium, and a biphasic change of the intracellular pH in cultured rat vascular smooth muscle cells. We conclude that low density lipoprotein occurring for example in the extravascular fluid can mediate vasoconstriction by changes in cytosolic calcium and intracellular pH.
Department of Internal Medicine, University Hospital, Zürich, Switzerland.
A
A
Sachinidis
R
R
Locher
T
T
Mengden
A
A
Steiner
W
W
Vetter
D000818:Animals; D002118:Calcium / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D008077:Lipoproteins, LDL / Q000494:pharmacology*; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000502:physiology; D051381:Rats; D014662:Vasoconstrictor Agents
D008077:Lipoproteins, LDL; D014662:Vasoconstrictor Agents; D002118:Calcium