Different subtypes of voltage-operated calcium channels (VOCCs) are expressed in different tissues and can be distinguished by functional and pharmacological criteria. One type of high voltage-activated calcium channel, specifically recognized by the peptide neurotoxin u-conotoxin (wCTx), is expressed only in neurons. Seven different human small cell lung carcinoma (SCC) cell lines were also fo...

The cellular events during the initiation and maintenance of ventricular fibrillation (VF) are poorly understood. We developed a nonischemic, isolated, perfused rabbit Langendorff preparation in which sustained VF could be induced by alternating current (AC) and which allowed changes in perfusate composition. We also used Na+-K+ pump inhibition (10 ,uM ouabain or K'-free perfusate) to induce VF...

Both local anaesthetics and calcium antagonists depress cardiac function. Therefore, we have studied the interaction of these compounds in the isolated myocardium of guineapigs. The negative inotropic effect of various local anaesthetics was investigated in left atria in the absence or presence of nitrendipine 10(-7) mol litre-1 (n = 7-8 in each group). In addition, the effect of bupivacaine wa...

The motile behavior and cytoskeletal structures of fish epidermal cells (keratocytes) in the presence and absence of direct current (DC) electric fields were examined. These cells spontaneously show highly directional locomotion in culture, migrating at rates of up to 1 micron/s. When DC electric fields between 0.5 and 15 V/cm are applied, single epidermal cells as well as cell clusters and cel...

The Syst-Eur trial investigated whether active treatment starting with the dihydropyridine calcium channel blocker (CCB) nitrendipine, could reduce the cardiovascular complications of isolated systolic hypertension (ISH) in the elderly. The intention-to-treat analysis showed that active treatment improved outcome. The per-protocol analysis largely confirmed these results. The effect of treatmen...

Diphenylhydantoin was studied for its effects on Ca currents in single isolated guinea pig ventricular cells. The whole-cell patch-clamp technique was used, and Ca currents were studied after suppressing Na and K currents. At low frequencies (0.1 Hz) and negative holding potentials (-50 mV), diphenylhydantoin produced a concentration-dependent decrease in Ca currents without any significant cha...

Background We wished to assess the respective roles of the antihypertensive and blood pressure (BP)-independent effects of antihypertensive drugs on arterial hemodynamics and left ventricular hypertrophy (LVH) in end-stage renal disease (ESRD) patients. Methods and Results In a double-blind study, 24 ESRD patients with LVH were randomized to 12 months' administration of either the angiotensin-c...

Serotonin (5-hydroxytryptamine; 5-HT) is a potent pulmonary vasoconstrictor and mitogenic agent whose plasma level is increased in pulmonary hypertensive patients. Thus, we explored the signalling pathways involved in the contractile response to 5-HT in human pulmonary arteries (HPAs). Intact and beta-escin permeabilised rings from HPAs mounted in an organ bath system were used to assess both t...

The interaction of SM-6586 (methyl 1,4-dihydro-2,6-dimethyl-3-[3-(N-benzyl-N-methyl-aminomethyl)-1,2,4- oxadiazolyl-5-yl]-4-(3-nitrophenyl)pyridine-5-carboxylate) with the specific binding of 3H-PN200-110 to rat heart and brain membranes was characterized and compared with those of other Ca2+ antagonists. The blockade of 3H-PN200-110 binding sites induced by nifedipine, nitrendipine and nimodip...

BACKGROUND After the double-blind, placebo-controlled Systolic Hypertension in Europe (Syst-Eur) trial ended in February 1997, randomized patients were offered active study medication for a further period of observation. OBJECTIVE To refine the estimates of the long-term effects of antihypertensive therapy on the incidence of dementia. METHODS Eligible patients had no dementia and were at l...