L-type calcium channels couple membrane depolarization in neurons to numerous processes including gene expression, synaptic efficacy, and cell survival. To establish the contribution of L-type calcium channels to various signaling cascades, investigators have relied on their unique pharmacological sensitivity to dihydropyridines. The traditional view of dihydropyridine-sensitive L-type calcium ...

N-type voltage-gated calcium channels localize to presynaptic nerve terminals and mediate key events including synaptogenesis and neurotransmission. While several kinases have been implicated in the modulation of calcium channels, their impact on presynaptic functions remains unclear. Here we report that the N-type calcium channel is a substrate for cyclin-dependent kinase 5 (Cdk5). The pore-fo...

Objective(s) Four novel losartan analogues 5a-d were synthesized by connecting a dihydropyridine nucleus to imidazole ring. The effects of 5a and 5b on angiotensin receptors (AT') and L-type calcium channels were investigated on isolated rat aorta. Materials and Methods Aortic rings were pre-contracted with 1 pM Angiotensin II or 80 mM KCl and relaxant effects of losartan, nifedipine, 5a and...

Tottering mice inherit a recessive mutation of the calcium channel alpha1A subunit that causes ataxia, polyspike discharges, and intermittent dystonic episodes. The calcium channel alpha1A subunit gene encodes the pore-forming protein of P/Q-type voltage-dependent calcium channels and is predominantly expressed in cerebellar granule and Purkinje neurons with moderate expression in hippocampus a...

Currents carried by L-, N-, and P/Q-type calcium channels do not account for the total calcium current in myenteric neurons. This study identified all calcium channels expressed by guinea pig small intestinal myenteric neurons maintained in primary culture. Calcium currents were recorded using whole cell techniques. Depolarizations (holding potential = -70 mV) elicited inward currents that were...

Multiple subtypes of voltage-gated calcium channels are differentially localized in brain neurons suggesting that they serve distinct roles in neuronal excitation and signaling. In organotypic hippocampal slice cultures, class D (L-type) calcium channels are predominantly located in the cell bodies of CA3 neurons while class B (N-type) and class A (P or Q-type) are localized in dendrites and as...

Calcium-induced calcium release (CICR) has been observed in cardiac myocytes as elementary calcium release events (calcium sparks) associated with the opening of L-type Ca(2+) channels. In heart cells, a tight coupling between the gating of single L-type Ca(2+) channels and ryanodine receptors (RYRs) underlies calcium release. Here we demonstrate that L-type Ca(2+) channels activate RYRs to pro...

objective(s) four novel losartan analogues 5a-d were synthesized by connecting a dihydropyridine nucleus to imidazole ring. the effects of 5a and 5b on angiotensin receptors (at') and l-type calcium channels were investigated on isolated rat aorta. materials and methods aortic rings were pre-contracted with 1 pm angiotensin ii or 80 mm kcl and relaxant effects of losartan, nifedipine, 5a a...

BACKGROUND Because knowledge about the type of calcium channels involved in action potential-induced norepinephrine release from the human peripheral sympathetic nervous system is sparse, we investigated which types of calcium channels are functionally important in the sympathetic nerves of human cardiac tissue. METHODS AND RESULTS In superfused segments of human right atrial appendages, the ...