In the vertebrate CNS, fast synaptic inhibition is mediated by GABA and glycine receptors. We recently reported that the time course of these synaptic currents is slower when intracellular chloride is high. Here we extend these findings to measure the effects of both extracellular and intracellular chloride on the deactivation of glycine and GABA currents at both negative and positive holding p...

Acid-activated chloride currents have been reported in several cell types and may play important roles in regulation of cell function. However, the molecular identities of the channels that mediate the currents are not defined. In this study, activation of the acid-induced chloride current and the possible candidates of the acid-activated chloride channel were investigated in human nasopharynge...

The continuous production of Clostridium tetani toxin has been carried out in a 1-liter stirred culture vessel for as long as 65 days. Toxin production of approximately 120 flocculating units per ml was maintained with a dilution rate of 0.125 hr(-1), a temperature of 34 C, a pH of 7.4, and the addition to the medium of 0.1 g of potassium chloride per liter. The average minimal lethal intraperi...

Based on a homology model of the Kv1.3 potassium channel, the recognitions of the six scorpion toxins, viz. agitoxin2, charybdotoxin, kaliotoxin, margatoxin, noxiustoxin, and Pandinus toxin, to the human Kv1.3 potassium channel have been investigated by using an approach of the Brownian dynamics (BD) simulation integrating molecular dynamics (MD) simulation. Reasonable three-dimensional structu...

Batrachotoxin (BTX), from South American frogs of the genus Phyllobates, irreversibly activates voltage-gated sodium channels. Previous work demonstrated that a phenylalanine residue approximately halfway through pore-lining transmembrane segment IVS6 is a critical determinant of channel sensitivity to BTX. In this study, we introduced a series of mutations at this site in the Na(v)1.3 sodium c...

An experimental model was established using the terminal ileum of the rat for characterizing and studying the effects of crude cell-free extract from Clostridium perfringens upon physiological and histological parameters involved in the transport process. Further work was done with the model system using purified enterotoxin (protein) from the cell extract. Using an in vivo perfusion technique ...