Drugs online research references
Arch Int Pharmacodyn Ther. 1983 Oct;265(2):274-82.
Mechanism of relaxant effects of nicorandil on the dog coronary artery.
Imai S, Ushijima T, Nakazawa M, Nabata H, Sakai K.
In order to search into the mechanism of the relaxant effects of nicorandil, a new coronary vasodilator, on the dog coronary artery, the effects of this substance on the potassium contracture were studied, and compared with those of nitroglycerin and nifedipine. All the three substances induced a dose-related relaxation (nifedipine greater than nitroglycerin greater than nicorandil). However, the increase in La3+-resistant 45Ca uptake was inhibited only by nifedipine. In a calcium-free EGTA containing medium caffeine induced a phasic contraction in the fully-depolarized preparation. Nicorandil produced an inhibition of this contraction, while nitroglycerin and nifedipine did not. It was concluded that nicorandil differs from the so-called calcium antagonists in the mechanism of relaxant action on the coronary artery. It also differs from nitroglycerin in that it produced an inhibition of caffeine-induced contraction.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6228201&dopt=Abstract
Br Heart J. 1983 May;49(5):442-6.
Coronary haemodynamic effects of nifedipine. Comparison with glyceryl trinitrate.
Stone DL, Stephens JD, Banim SO.
The coronary haemodynamic effects of nifedipine and glyceryl trinitrate were compared in 22 patients undergoing investigations for suspected coronary artery disease. Myocardial blood flow was estimated by the coronary sinus thermodilution technique. In sinus rhythm nifedipine increased mean coronary sinus flow from 135 ml/min to 152 ml/min, and reduced arterio-coronary sinus oxygen difference from 12.4 to 10.96 ml/100 ml without causing a significant change in coronary vascular resistance or in myocardial oxygen consumption. Glyceryl trinitrate reduced mean coronary sinus flow from 165 to 111 ml/min, myocardial oxygen consumption from 19.2 to 11.9 ml/min, and arterio-coronary sinus oxygen difference from 11.7 to 10.9 ml/100 ml. There was a rise in coronary vascular resistance from 54 355 to 74 364 dynes s cm-5. During atrial pacing nifedipine reduced the arterio-coronary sinus oxygen difference from 11.99 to 11.0 ml/100 ml but had no significant effect on the other variables measured. Glyceryl trinitrate caused a fall in mean coronary sinus flow from 207 ml/min to 168 ml/min; myocardial oxygen consumption fell from 24 ml/min to 18 ml/min, while coronary vascular resistance rose from 41 714 to 51 234 dynes s cm-5. Direct comparison of the two drugs showed a significant difference in effects on coronary sinus flow and coronary vascular resistance in sinus rhythm. Both drugs appeared effective in relieving ischaemia as judged by a reduction of the incidence of pacing induced angina and an improvement in lactate status.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6404288&dopt=Abstract
J Asthma. 1984;21(6):419-26.
Calcium channel blocking agents in bronchial hyperreactivity.
Solway J.
A variety of clinical and animal bronchial challenge experiments have been undertaken to assess the efficacy and sites of action of the calcium channel blockers nifedipine and verapamil in blunting bronchoconstriction. Nifedipine appears to be the more effective of these agents, and it blunts the airways response to methacholine and histamine inhalation as well as the bronchoconstriction caused by exercise or cold air hyperpnea. The mechanism by which it acts is difficult to define with certainty because of the widely distributed role of calcium ion within the bronchoconstriction pathways, but nifedipine appears to exert a direct effect on airway wall smooth muscle as well as a possible influence on mast cell mediator release.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6396294&dopt=Abstract
Herbs and Pharmaceuticals Online ||
Hair Million herbal formula for hair loss and hair growth ||
Wellstreet online pharmacy for click-order prescription medications ||
Altace Online Pharmacy ||
Rx Drugs USA, Prescription Drugs Online Pharmacy ||
Insurance plans and information ||
Insurance policies for all purposes ||
Antibiotics and prescription medications online literature ||