Regulation of intracellular calcium influences neuronal excitability, synaptic plasticity, gene expression, and neurotoxicity. In this study, we investigated the role of calcium in mechanisms underlying nicotine-mediated neuroprotection from glutamate excitotoxicity. Neuroprotection by nicotine in primary cortical cultures was not seen in knock-out mice lacking the beta2 subunit of the nicotini...

Previous studies have demonstrated multiple components of whole-cell calcium currents in hypoglossal motoneurons (HMs); HMs possess a low-voltage-activated (LVA) current and three types of high-voltage-activated (HVA) calcium currents based on sensitivity to omega-Aga IVA, omega-Conotoxin GVIA (omega-CgTx) and dihydropyridine analogs (DHPs). In the present study, we recorded single-calcium chan...

Glutamate is the primary excitatory transmitter in the suprachiasmatic nucleus (SCN). Ionotropic glutamate receptors (iGluRs) mediate transduction of light information from the retina to the SCN, an important circadian clock phase shifting pathway. Metabotropic glutamate receptors (mGluRs) may play a significant modulatory role. mGluR modulation of SCN responses to glutamate was investigated wi...

introduction: dill (anethum graveolens), a herb from from umbelliferae, is used traditionally to treat convulsion and increasing milk production. its antimicrobial, antihyperlipidaemic, anti-hypercholesteroaemic effects and gastric acid secretion reducing effect have been reported. the spasmolytic effect of dill fruit on rat uterus has also been shown recently. the aim of present study was to i...

It is now clear that the wide variety of neuronal voltage-dependent calcium channels (Table 1) are determinants of transmitter release (N-type, P-type, Q-type channels), repetitive or burst neuronal firing (T-type channels) and perhaps of some aspects of gene expression (L-type channels). However, although the calcium overload hypothesis of neuronal cell death has been around for 14 years, ther...

This review summarizes recent advances in our understanding of neuronal T-type calcium channel regulation as well as their physiological and pathophysiological roles. Through their ability to conduct calcium across the cellular membrane at potentials close to the resting potential, T-type calcium channels are critically important for regulating neuronal excitability, both in the central and per...

Calcium influx is an absolute requirement for the physiological acrosome reaction in sperm from all sources examined, both invertebrate and mammalian. Pharmacological studies suggest that the major channel in the sperm head plasma membrane responsible for modulating calcium entry and intracellular ionized calcium levels could be either an L-type (a class of high voltage-activated) or a T-type (...