Resurgent Na+ current: a new avenue to neuronal excitability control.

Integrative and firing properties are important characteristics of neuronal circuits and these responses are determined in large part by the repertoire of ion channels they express, which can vary considerably between cell types. Recently, a new mode of operation of voltage dependent sodium channels has been described that generates a so-called resurgent Na+ current. Accumulating evidence suggests resurgent Na current participates in the generation of sub-threshold inward Na+ current causing membrane depolarization which provides the necessary drive to fire high-frequency action potentials.

Pharmacokinetics of the venom of Bothrops erythromelas labeled with 131I in mice.

Bothrops erythromelas venom (BeV) has been responsible for many snake accidents in Brazil. We investigated the plasmatic pharmacokinetic of BeV labeled with (131)I in the absence and the presence of anti-Bothrops serum (BAS). A higher percentage of BeV plasmatic radioactivity and longer elimination were found in the presence of BAS.