Cultured human vascular smooth muscle cells with functional thromboxane A2 receptors: measurement of U46619-induced /sup 45/calcium efflux

Journal Article · Mon Jun 01 00:00:00 EDT 1987 · Circ. Res.; (United States)

DOI:https://doi.org/10.1161/01.RES.60.6.952· OSTI ID:6173711

Dorn, II, G W; Sens, D; Chaikhouni, A; Mais, D; Halushka, P V

Thromboxane A2 (TXA2)/prostaglandin H2 (PGH2) are potent vasoconstrictors whose contractile effects are mediated by increases in cellular calcium. Stable analogues of these compounds have shown calcium ionophore activity at high concentrations. To determine if effects of TXA2/PGH2 analogues on /sup 45/Ca/sup 2 +/ fluxes are receptor mediated, the effects of the stable TXA2/PGH2 mimetic U46619 and the TXA2/PGH2 receptor antagonist I-PTA-OH on /sup 45/Ca/+ fluxes in cultured human vascular smooth muscle cells were studied. The smooth muscle cells were cultured from human saphenous vein explants, and they retained the morphologic and immunologic characteristics of vascular smooth muscle cells. U46619 stimulated /sup 45/Ca/sup 2 +/ efflux in a dose-dependent manner with an EC50 of 398 +/- 26 nM (n = 4). The maximal /sup 45/Ca/sup 2 +/ efflux in response to U46619 (5 microM) was significantly greater (p = 0.006) than the /sup 45/Ca/sup 2 +/ efflux induced by KCl (40 mM). I-PTA-OH inhibited the U46619-induced /sup 45/Ca/sup 2 +/ efflux but had no effect on KCl-induced /sup 45/Ca/sup 2 +/ efflux. These results suggest that the effects of U46619 in increasing vascular smooth muscle cell calcium efflux are receptor mediated. Furthermore, vascular smooth muscle cells with functional TXA2/PGH2 receptors were cultured from human saphenous veins and provide a potentially useful in vitro system for the further study of TXA2/PGH2 receptor-mediated phenomena in human vascular tissue.

• Research Organization: Medical Univ. of South Carolina, Charleston
• OSTI ID: 6173711
• Journal Information: Circ. Res.; (United States), Vol. 60:6
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CALCIUM COMPOUNDS
MEMBRANE TRANSPORT
PROSTAGLANDINS
RECEPTORS
VASOCONSTRICTORS
CALCIUM 45
CELL CULTURES
DOSE-RESPONSE RELATIONSHIPS
MAN
MUSCLES
TRACER TECHNIQUES
ALKALINE EARTH ISOTOPES
ALKALINE EARTH METAL COMPOUNDS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CALCIUM ISOTOPES
CARDIOVASCULAR AGENTS
DAYS LIVING RADIOISOTOPES
DRUGS
EVEN-ODD NUCLEI
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
MAMMALS
MEMBRANE PROTEINS
NUCLEI
ORGANIC COMPOUNDS
PRIMATES
PROTEINS
RADIOISOTOPES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques