Since the initial identification of native calcium currents, significant progress has been made towards our understanding of the molecular and cellular contributions of voltage-gated calcium channels in multiple physiological processes. Moreover, we are beginning to comprehend their pathophysiological roles through both naturally occurring channelopathies in humans and mice and through targeted...

Quantum chemical (MNDo)caleulations have beenused toelucidate the molecular properties and structure - activity relationships of dihydropyridine (DHP) type calcium antagonists. There is a good corielation between the net atomic charges on various atoms of the 4 - phenyl ring of dihydropyridines and pharmacological activity. .Also, activity decreases with increasing free rotation of the phen...

Several studies have suggested that high blood pressure is associated with the risk of bone loss. Since various antihypertensive drugs are in wide use for the treatment of hypertension, it is important to investigate the influences of these drugs on bone metabolism. Osteoblasts play a pivotal role in the regulation of bone formation. During differentiation, they sequentially express type I coll...

[(3)H]Nitrendipine, a potent calcium channel antagonist [3-ethyl-5-methyl-1-1,4-dihydro-2,6 - dimethyl - 4 - (3 - nitrophenyl) - 3,5 - pyridine carboxylate], was used to label high affinity binding sites on membranes prepared from bovine aortic smooth muscle. The binding of [(3)H]nitrendipine is rapid (t(1/2) < 5 min) and reversible at 37 degrees C. The binding sites have a high affinity for [(...

BACKGROUND The endothelium-derived relaxing factor has been shown to be nitric oxide or a related nitroso compound, synthesized by the enzyme nitric oxide synthetase, which oxidizes the guanidono nitrogens of arginine. This enzyme is activated by increases in cytosolic calcium. The effect of the clinically used calcium channel antagonists on this process is controversial. The present study was ...

The relationship between systemic blood pressure and glomerular capillary pressure (Pgc) in spontaneously hypertensive rats (SHR) during treatment with antihypertensive drugs is still unclear. The effects of an angiotensin-converting enzyme inhibitor (enalapril), two calcium channel antagonists (nifedipine and verapamil), and an α1-receptor blocker (doxazosin) on renal blood flow (RBF) autoregu...

In response to retinal disease and injury, the axon terminals of rod photoreceptors demonstrate dramatic structural plasticity, including axonal retraction, neurite extension, and the development of presynaptic varicosities. Cone cell terminals, however, are relatively inactive. Similar events are observed in primary cultures of salamander photoreceptors. To investigate the mechanisms underlyin...

The molecular heterogeneity of voltage-gated calcium channels is mirrored by extensive biophysical diversity. Subtype-selective antagonists have been used to place different kinds of calcium channels in functional categories. Dihydropyridine (DHP) antagonists have been used, for example, to implicate L-type calcium channels in the induction of NMDA receptor-independent forms of synaptic plastic...

STUDY OBJECTIVE Acute renal colic is a common presenting complaint to the emergency department. Recently, medical expulsive therapy using alpha-antagonists or calcium channel blockers has been shown to augment stone passage rates of moderately sized, distal, ureteral stones. Herein is a systematic evaluation of the use of medical expulsive therapy to facilitate ureteral stone expulsion. METHO...