Interaction of glutamate- and adenosine-induced decrease of acetylcholine quantal release at frog neuromuscular junction

Title:

Interaction of glutamate- and adenosine-induced decrease of acetylcholine quantal release at frog neuromuscular junction

Creator:

Svatopluk Adámek, Shakirzyanova, A. V., Malomouzh, A. I., Naumenko, N. V., and Vyskočil, F.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:bf0e04a0-0397-42f1-94c5-a476a260cf24
uuid:bf0e04a0-0397-42f1-94c5-a476a260cf24

Subject:

Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, endplate potentials, guanylyl cyclase, carbacholine, ATP, NO, 14, and 612

Type:

article, články, model:article, and TEXT

Format:

print

Description:

In a frog neuromuscular preparation of m. sartorius, glutamate had a reversible dose-dependent inhibitory effect on both spontaneous miniature endplate potentials (MEPP) and nerve stimulation-evoked endplate potentials (EPP). The effect of glutamate on MEPP and EPP is caused by the activation of metabotropic glutamate receptors, as it was eliminated by MCPG, an inhibitor of group I metabotropic glutamate receptors. The depression of evoked EPP, but not MEPP frequency was removed by inhibiting the NO production in the muscle by L-NAME and by ODQ that inhibits the soluble NO-sensitive guanylyl cyclase. The glutamate-induced depression of the frequency of spontaneous MEPP is apparently not caused by the stimulation of the NO cascade. The particular glutamate-stimulated NO cascade affecting the evoked EPP can be down-regulated also by adenosine receptors, as the glutamate and adenosine actions are not additive and application of adenosine partially prevents the further decrease of quantal content by glutamate. On the other hand, there is no obvious interaction between the glutamatemediated inhibition of EPP and inhibitory pathways triggered by carbacholine and ATP. The effect of glutamate on the evoked EPP release might be due to NO-mediated modulation (phosphorylation) of the voltage-dependent Ca2+ channels at the presynaptic release zone that are necessary for evoked quantal release and open during EPP production., S. Adámek ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy

Language:

English

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Source:

Physiological research | 2010 Volume:59 | Number:5

Harvested from:

CDK

Metadata only:

false