Antiproteinuric effect of calcium antagonists on puromycin-induced experimental nephrosis

Pharmacologic treatment of chronic pediatric hypertension

Improved recognition of the relationship between childhood and adult blood pressures and identification of end-organ damage in children, adolescents, and young adults with hypertension has led to increased focus by pediatricians and general practitioners on the detection, evaluation, and treatment of hypertension. Notably, detection, evaluation, and treatment of pediatric hypertension has increased significantly since the first Task Force Report on High Blood Pressure in Children and Adolescents in 1977 with advances in both nonpharmacologic and pharmacologic treatments.Angiotensin-converting enzyme inhibitors (e.g. captopril, enalapril, lisinopril, ramipril) and calcium channel antagonists (e.g. nifedipine, amlodipine, felodipine, isradipine) are the most commonly prescribed antihypertensive medications in children due to their low adverse-effect profiles. Diuretics (e.g. thiazide diuretics, loop diuretics, and potassium-sparing diuretics) are usually reserved as adjunct therapy. Newer agents, such as angiotensin receptor antagonists (e.g. irbesartan), are currently being studied in children and adolescents. These agents may be an option in children with chronic cough secondary to angiotensin-converting enzyme inhibitors. beta-Adrenoreceptor antagonists (e.g. propranolol, atenolol, metoprolol, and labetalol), alpha-adrenoreceptor antagonists, alpha-adrenoreceptor agonists, direct vasodilators, peripheral adrenoreceptor neuron agonists, and combination products are less commonly used in pediatric patients because of adverse events but may be an option in children unresponsive to calcium channel blockers, angiotensin converting-enzyme inhibitors, or angiotensin receptor blockers.

Are calcium antagonists effective in preventing complications of hypertension and progression of renal disease?

Long-acting calcium antagonists have been shown to be safe and effective in lowering blood pressure, both as first-line agents and in combination with other classes of antihypertensive drug. They have also been shown to reduce the incidence of cerebrovascular and cardiovascular events in elderly patients with predominantly systolic hypertension. It is clear that reduced morbidity and mortality in hypertension is related to the degree to which blood pressure is reduced, regardless of the therapy used. This is the single most important conclusion of all recent trials, especially in the sub-group of hypertensive patients with diabetes. The World Health Organization-International Society of Hypertension guidelines acknowledge this and do not make specific recommendations as to initial therapy in the absence of other medical factors. However the use of thiazide diuretics and beta-blockers has strong support from large placebo-controlled trials in patients with mild-moderate essential hypertension. The British Hypertension Society and JNC VI guidelines restrict their recommendations for the use of calcium antagonists to isolated systolic hypertension and angina, or when other agents have failed, are contraindicated or are not tolerated. However, their efficacy in lowering blood pressure, their tolerability and potentially beneficial secondary effect on proteinuria, especially in combination with an angiotensin-converting enzyme inhibitor, still make them attractive antihypertensive agents. The results of further long-term outcome trials that make direct comparisons between calcium antagonists and other classes of antihypertensive drug are still awaited. Unlike angiotensin-converting enzyme inhibitors, the antiproteinuric effect of calcium antagonists, even that of the non-dihydropyridine type, seems to depend on an adequate and stable reduction in blood pressure.