Possible mechanisms underlying effects of N-uronoyl derivatives of amino acids on electrical activity in snail neurons

Authors: Korenyuk, I.; Ravaeva, M.1

Source: Neurophysiology, Volume 38, Numbers 5-6, September 2006 , pp. 351-359(9)

Publisher: Springer

Key:
Free Content - Free Content
New Content - New Content
Subscribed Content - Subscribed Content
Free Trial Content - Free Trial Content

Abstract:

Using intracellular recording, we studied the effects of N-uronoyl derivatives of an amino acid and peptides (1,2:3,4-di-O-isopropylidene-αa-D-galactopyranuronoyl)-β-alanine (DAGU-Ala), DAGU-glycyl-glycine (DAGU-Gly-Gly), DAGU-glycyl-D,L-glutamic acid (DAGU-Gly-Glu), as well as of 1,2:3,4-di-O-isopropylidene-αa-D-galactopyranosyluronic acid (DAGU itself), β-alanine (β-Ala), D,L-glutamic acid (D,L-Glu), and glycyl-glycine (Gly-Gly), which were added to the extracellular milieu, on the electrical activity of PPa1 and PPa2 neurons and unidentified neurons of Helix albescens Rossm. DAGU-Gly-Gly applied in concentrations of 10−4 to 10−2 M hyperpolarized the membrane in a dose-dependent manner and decreased insignificantly the amplitude of action potentials (APs). Applications of DAGU-Ala, β-Ala, DAGU-Gly-Glu, D,L-Glu, and Gly-Gly in the same doses resulted in a shift of the membrane potential toward depolarization and in a drop in the amplitude of APs. Measurements of the first AP derivatives showed that all the above-mentioned substances suppressed in a concentration-dependent manner both inward and outward transmembrane ion currents. In this case, DAGU suppressed both inward and outward currents, while DAGU-Ala, β-Ala, DAGU-Glu, D,L-Glu, and Gly-Gly inhibited predominantly the outward potassium ion current; DAGU-Gly-Gly inhibited inward sodium and potassium ion currents. Results of a comparative analysis of the neurotropic action of the tested amino acids and their N-uronoyl derivatives showed that modification of the molecules of neurotransmitter amino acids leads to a decrease in their neurotoxicity and to an increase in their membranotropic properties.

Keywords: molluscan neurons; potentials; transmembrane ion currents; N-uronoyl derivatives of amino acids

Document Type: Research article

DOI: 10.1007/s11062-006-0071-5

Affiliations: 1: Email: mravaeva@ukr.net

The full text electronic article is available for purchase. You will be able to download the full text electronic article after payment.

$47.00 plus tax

 

OR

Back to top

Key:
Free Content - Free Content
New Content - New Content
Subscribed Content - Subscribed Content
Free Trial Content - Free Trial Content
Page Help Click here for Page Help
Shopping cart
Tools
Sign in






Need to register?
Sign up here
Text size: A | A | A | A