The effects of Bay K 8644 on the high-threshold calcium channel was investigated by means of the whole-cell patch-clamp technique in single guinea pig ventricular myocytes. The goal of the experiments was to characterize the inhibitory effects of Bay K 8644 on the calcium channel, and identify the factors that influence the inhibition. Bay K 8644 was found to have strong calcium channel antagon...

hronic stable angina (CSA) represents the largest cardiovascular disorder in the United States and is the initial clinical presentation of ischemic heart disease in 50% of patients. CSA is the result of the progression of coronary atherosclerosis and becomes symptomatic once the luminal diameter of the vessel is occluded by >50%. Current medical therapy is targeted at reducing the frequency of ...

The vanilloid receptor 1 (VR1) is a ligand-gated, nonselective cation channel important for the sensory processing of painful stimuli. Activation of VR1 leads to increases in intracellular concentrations of calcium and sodium. Prolonged activation of VR1 in mammalian expression systems leads to cell death. The mechanism of VR1-mediated toxicity may have relevance to pathophysiological processes...

Calcium channel and beta-adrenergic receptor antagonists are common pharmaceutical agents with multiple overlapping clinical indications. When used appropriately, these agents are safe and efficacious. In overdose, however, these agents have the potential for serious morbidity. Calcium channel blockers and beta blockers share similar physiological effects on the cardiovascular system, such as h...

The influence of calcium channel antagonists on the behavioral sensitization to nicotine-induced hyperlocomotion and place preference was investigated. Locomotor sensitization in mice was produced by injecting nicotine (0.5 mg/kg, i.p.) for 5 consecutive days before placement in an apparatus in which locomotor activity was evaluated for 1 h. One week later, activity of mice was recorded after c...

Using intracellular recording, we studied how several muscarinic antagonists affected the evoked endplate potentials in singly and dually innervated endplates of the levator auris longus muscle from 3 to 6-day-old rats. In dually innervated fibers, a second endplate potential (EPP) may appear after the first one when we increase the stimulation intensity. The lowest and highest EPP amplitudes a...

Background: Among anti-hypertension drugs, calcium (Ca) antagonists cause gingival overgrowth as a side effect. We previously discovered that this side effect was due to elevation of the calcium concentration in the cytosol ([Ca]i). Ca entry through non-selective cation channels (NSCCs) and Ca release from intracellular Ca stores are involved in this [Ca]i elevation. Furthermore, we discovered ...

The aim of this study was to assess the effect of three calcium channel antagonists (amlodipine, diltiazem and verapamil) on the anticonvulsant action of lamotrigine (a second generation antiepileptic drug) against maximal electroshock-induced seizures in mice. Results indicated that all three calcium channel antagonists when administered alone [amlodipine (up to 20 mg/kg, ip), diltiazem (up to...