[Peptide components of Geolycosa spider venom modulate P2X receptor activity of rat sensory neurons].

Almost each natural venom comprises a considerable combinatorial library of bioactive substances that have been optimized during evolution. Particular attention is devoted currently on a search for new modulators of ion channels from the venoms of arthropods. We have studied the effect of peptidous compounds of the Lycosa spider venom on the activity of P2X receptors in DRG neurons of rats.

[Adaptation of synaptic transmission to high concentrations of homocysteinic acid].

Prolonged incubation with 25 microM homocysteine acid led to initial suppression of the synaptic transmission, which in 6 out of 12 cases was followed by the restoration of the population spike to values 63% from the control. In the rest of experiments, a transient decrease of the population spike amplitude was observed during wash-out of homocysteine acid. Such a pattern suggests that synaptic transmission has special mechanisms for adaptation to increasing concentrations of the excitatory amino acids which are potentially damaging.

[Interneuronal signaling mediated by the trans-synaptic diffusion of neurotransmitters].

A great number of modern neurophysiological studies give evidence about the possibility of the extrasynaptic diffusion of the released neurotransmitters. Such observations challenge the established view on synapses as isolated communication channels between pre- and postsynaptic neurones. In the present review article, we consider the latest experimental data on the interneuronal cross-talk mediated by extrasynaptic diffusion of L-glutamate (L-Glu) and gamma-amino-butyric acid (GABA).