Calcium channel blocking agents

Despite the growth in interest in calcium blockers, there are comparatively few calcium channel blocking agents currently in clinical use. These drugs are characterised by the fact that they belong to classes of compounds which are chemically unrelated like Diltiazem , Nifedipine , Verapamil , Fluspirilene and some others (Scheme 1). 

ACE-I, angiotensin-converting enzyme inhibitor Aid Ant, aldosterone antagonist ARB, angiotensin receptor blocker BB, beta-blocker CCBA, calcium channel blocking agent DirVaso, direct vasodilator. 

Chymostatin-sensitive Il-generating enzyme Carvedilol Post-Infarct Survival Control in Left Ventricular Dysfunction Trial Collaborative Study Captopril Trial ( The Effect of Angiotensin-Converting Enzyme Inhibition on Diabetic Nephropathy ) calcium channel blocking agents Candesartan in Heart Failure Assessment of Reduction in Morbidity and Mortality Trial congestive heart failure, but the latest recommendations use HF for heart failure chronic kidney disease cardiac output... 

Landon EJ, Naukam RJ, Sastry BVR. 1986. Effects of calcium channel blocking agents on calcium and centrilobular necrosis in the liver of rats treated with hepatotoxic agents. Biochem Pharmacol 35 697-705. 

Q22 Pharmacological effects of calcium-channel blocking agents may... 

The pharmacokinetic properties of these drugs are set forth in Table 12-5. The choice of a particular calcium channel-blocking agent should be made with knowledge of its specific potential adverse effects as well as its pharmacologic properties. Nifedipine does not decrease atrioventricular conduction and therefore can be used more safely than verapamil or diltiazem in the presence of atrioventricular conduction abnormalities. A combination of verapamil or diltiazem with 3 blockers may produce atrioventricular block and depression of ventricular function. In the presence of overt heart failure, all calcium channel blockers can cause further worsening of heart failure as a result of their negative inotropic effect. Amlodipine, however, does not increase the mortality of patients with heart failure due to nonischemic left ventricular systolic dysfunction and can be used safely in these patients. 

J Das, DM Floyd, SM Kimball, RN Patel, JK Thottathil. Chemoenzymatic synthesis of benzazepinone calcium channel blocking agents. Indian J Chem 31B 817-820, 1992. 

The studied molecules include such diverse compounds as volatile anesthetics (halothane), local anesthetics of the cocaine type, calcium channel-blocking agents such as verapamil, antidepressants (chlorpromazine), and anti cancer drugs such as adriamycin. It is argued that the factor of interest to the physiological effect may not... 

Shimada, S., Nakajima, Y., Yamamoto, K., Sawada, Y., and Iga, T., Comparative pharmacodynamics of eight calcium channel blocking agents in Japanese essential hypertensive patients, Biological and Pharmaceutical Bulletin, Vol. 19, No. 3, 1996, pp. 430-437. 

The Hantzsch pyridine synthesis is an old discovery (1882) which sprang into prominence in the 1980s with the discovery that the dihydropyridine intermediates prepared from aromatic aldehydes are calcium channel blocking agents and therefore valuable drugs for heart disease with useful effects on angina and hypertension. 

Calcium channel blocking agents, such as verapamil and nifedipine are also satisfactory antihypertensive agents. These drugs reduce the influx of calcium ions into vascular muscle cells following excitation and so cause vasodilation. They act mainly on arterial vessels in the circulation. 

Q4 Constipation can be a troublesome side effect of opiates used for pain relief, for example morphine and codeine. It is also a side effect of some calcium channel blocking agents, antacids containing aluminium compounds and iron salts used in the treatment of anaemia. 

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