Studies of the voltage-sensitive calcium channels in smooth muscle, neuronal, and cardiac tissues using 1,4-dihydropyridine calcium channel antagonists and activators

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1988

OSTI ID:6983883

Wei, X

This study describes the investigation of the voltage-sensitive Ca{sup +} channels in vascular and intestinal smooth muscle, chick neural retina cells and neonatal rat cardiac myocytes using 1,4-dihydropyridine Ca{sup 2+} channel antagonists and activators. In rat aorta, the tumor promoting phorbol ester, 12-O-tetradecanoylphorbol-13-acetate (TPA) produced Ca{sup 2+}-dependent contractile responses. The responses to TPA were blocked by the Ca{sup 2+} channel antagonists. The effects of the enantiomers of Bay K 8644 and 202-791 were characterized in both rat tail artery and guinea pig ileal longitudinal smooth muscle preparations using pharmacologic and radioligand binding assays. The (S)-enantiomers induced contraction and potentiated the responses to K{sup +} depolarization. The (R)-enantiomers inhibited the tension responses to K{sup +}. All the enantiomers inhibited specific ({sup 3}H)nitrendipine binding. The pharmacologic activities of both activator and antagonist ligands correlated on a 1:1 basis with the binding affinities. In chick neural retina cells the (S)-enantiomers of Bay K 8644 and 202-791 enhanced Ca{sup 2+} influx. In contrast, the (R)-enantiomers inhibited Ca{sup 2+} influx. The enantiomers of Bay K 8644 and 202-791 inhibited specific ({sup 3}H)PN 200-110 binding competitively. Binding of 1,4-dihydropyridines was characterized in neonatal rat heart cells.

• Research Organization: State Univ. of New York, Buffalo, NY (USA)
• OSTI ID: 6983883
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
560300 -- Chemicals Metabolism & Toxicology
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALKALINE EARTH METAL COMPOUNDS
ANIMAL CELLS
ANIMALS
AORTA
ARTERIES
AZINES
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL EFFECTS
BIRDS
BLOOD VESSELS
BODY
BODY AREAS
CALCIUM COMPOUNDS
CARCINOGENS
CARDIOVASCULAR SYSTEM
CHICKENS
ENZYME ACTIVITY
ENZYMES
ESTERS
EYES
FACE
FOWL
GUINEA PIGS
HEAD
HEART
HETEROCYCLIC COMPOUNDS
HYDROGEN COMPOUNDS
ISOTOPE APPLICATIONS
KINETICS
MAMMALS
MUSCLES
NEONATES
NERVE CELLS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
PHORBOL ESTERS
PHOSPHORUS-GROUP TRANSFERASES
PHOSPHOTRANSFERASES
PYRIDINES
RADIOASSAY
RATS
REACTION KINETICS
RETINA
RODENTS
SENSE ORGANS
SOMATIC CELLS
TRACER TECHNIQUES
TRANSFERASES
TRITIUM COMPOUNDS
VERTEBRATES