Biomaterial Database

Effects of nifedipine on contractile responses to potassium, histamine, and 5-hydroxytryptamine in isolated human pulmonary vessels. 1983

E O Mikkelsen, and A M Sakr, and L T Jespersen

Isolated human pulmonary arteries and veins cut to ring preparations responded with maximum contractions to potassium (127 mM; K), histamine (90 microM), and 5-hydroxytryptamine (47 microM; 5-HT). Nifedipine (0.003-3 microM) had a concentration-dependent relaxant effect on contractions induced by K, histamine, or 5-HT. The magnitudes of the relaxant effect of nifedipine were equal in arteries and veins, except in the highest concentrations used, in which case the effect was more pronounced on K-induced contractions in veins than in arteries. The effect of nifedipine was less pronounced on contractions induced by histamine or 5-HT than on K-induced contractions, and was more pronounced on histamine- than on 5-HT-induced contractions. In Ca-free medium, the response to K was nearly abolished in both arteries and veins. When the Ca concentration was increased from 0 to 4 mM without nifedipine, the contractile response to K was completely restored, while in the presence of nifedipine the response to extracellular Ca was nearly abolished in both types of vessel. The results indicate that active tone induced by K in pulmonary vessels is dependent on Ca entry from the extracellular medium. Nifedipine has a relaxant effect on both arteries and veins. In both types of vessel contractions induced by histamine or 5-HT are more resistant to the effect of nifedipine than contractions mediated by depolarization.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D009543	Nifedipine	A potent vasodilator agent with calcium antagonistic action. It is a useful anti-anginal agent that also lowers blood pressure.	Adalat,BAY-a-1040,Bay-1040,Cordipin,Cordipine,Corinfar,Fenigidin,Korinfar,Nifangin,Nifedipine Monohydrochloride,Nifedipine-GTIS,Procardia,Procardia XL,Vascard,BAY a 1040,BAYa1040,Bay 1040,Bay1040,Monohydrochloride, Nifedipine,Nifedipine GTIS
D011188	Potassium	An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
D011651	Pulmonary Artery	The short wide vessel arising from the conus arteriosus of the right ventricle and conveying unaerated blood to the lungs.	Arteries, Pulmonary,Artery, Pulmonary,Pulmonary Arteries
D011667	Pulmonary Veins	The veins that return the oxygenated blood from the lungs to the left atrium of the heart.	Pulmonary Vein,Vein, Pulmonary,Veins, Pulmonary
D011725	Pyridines	Compounds with a six membered aromatic ring containing NITROGEN. The saturated version is PIPERIDINES.
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D005260	Female		Females