In this study, we investigated the mechanism that links activation of N-methyl-D-aspartate (NMDA) receptors to inhibition of voltage-gated sodium channels in isolated catfish cone horizontal cells. NMDA channels were activated in voltage-clamped cells incubated in low-calcium saline or dialyzed with the calcium chelator BAPTA to determine that calcium influx through NMDA channels is required fo...

Hippocampal mossy fiber long-term potentiation (LTP) is expressed presynaptically, but the exact mechanisms remain unknown. Here, we demonstrate the involvement of the hyperpolarization-activated cation channel (Ih) in the expression of mossy fiber LTP. Established LTP was blocked and reversed by Ih channel antagonists. Whole-cell recording from granule cells revealed that repetitive stimulatio...

The aim of this paper is to review available data about drugs for preventing preterm labour. Tocolytic therapy includes β adrenergic receptor agonists, NO donors, magnesium sulphate, prostaglandin-synthase inhibitors, oxytocin receptor antagonists, calcium-channel blockers, progesterone, 17-α-hydroxyprogesterone caproate, and antibiotics. Their specific effects on myometrial contractility, thei...

Stable angina pectoris is characterised by typical exertional chest pain that is relieved by rest or nitrates. Risk stratification of patients is important to define prognosis, to guide medical management and to select patients suitable for revascularisation. Medical treatment aims to relieve angina and prevent cardiovascular events. Beta blockers and calcium channel antagonists are first-line ...

Large-conductance calcium-activated potassium BK channels are widely expressed in the brain and are involved in the regulation of neuronal functions such as neurotransmitter release. However, their possible role in mediating ethanol-induced GABA release is still unknown. We assessed the role of BK channels in modulating the action of ethanol on inhibitory synaptic transmission mediated via GABA...

Short-term treatment of the endothelium with dihydropyridine calcium antagonists resulted in an increased release in NO that is not due to a modulation of L-type calcium channels, because macrovascular endothelial cells do not express this channel. We investigated whether long-term (48 hours) treatment of porcine endothelial cell cultures with the dihydropyridine calcium antagonist nifedipine r...

We report the case of a 42-year-old man with no risk factors for coronary artery disease admitted with atypical chest pain. The electrocardiogram performed after intravenous injection of nitrate revealed ST-segment elevation in leads V1 to V4. The coronary angiography showed myocardial bridges in the three coronary arteries, besides an unusual length of the left anterior descending artery (80 m...

The primary mode of action of local anesthetics is through sodium channel and axonal conduction blockade. Local anesthetics have also extensive effects on pre-synaptic calcium channels that must function to stimulate the release of neurotransmitters. Thus, interference with calcium channel conductance may enhance spinal anesthesia with local anesthetics. The present study was designed to invest...

The primary mode of action of local anesthetics is through sodium channel and axonal conduction blockade. Local anesthetics have also extensive effects on pre-synaptic calcium channels that must function to stimulate the release of neurotransmitters. Thus, interference with calcium channel conductance may enhance spinal anesthesia with local anesthetics. The present study was designed to invest...

Cerebral vasospasm (CVS) is the most treatable component of subarachnoid hemorrhage (SAH), which can be reduced by endothelin receptor antagonists. Endothelin-evoked vasospasm is considered to be mediated by Ca(2+) influx in the smooth muscle through voltage-dependent Ca(2+) channel (VDCC) and nonselective cation channels (NSCC). Because VDCC antagonists such as nimodipine have been shown to be...