当前位置： SCI文献检索 > JOURNAL OF NEUROCHEMISTRY期刊下所有文献 > Effect of presynaptic P2 receptor stimulation on transmitter release.

Effect of presynaptic P2 receptor stimulation on transmitter release.

Abstract：

:Because ATP is degraded to adenosine, its effect could be mediated by both P1 and P2 receptors. Hence, the actions of an ATP analogue, resistant to enzymatic breakdown (alpha, beta-methylene ATP), were studied on the resting and electrically evoked release of radioactivity from longitudinal muscle strips of guinea pig ileum, preloaded either with [3H]choline or with [3H]noradrenaline. Their effects were compared with the actions of adenosine and ATP. Although adenosine and ATP markedly decreased the [3H]acetylcholine release evoked by field stimulation, alpha,beta-methylene-ATP, a potent and selective agonist of P2x receptors, enhanced this release. However, 2-methyl-2-thio-ATP, an agonist of the P2y receptors, neither enhanced nor inhibited the [3H]-acetylcholine release. 8-Phenyltheophylline, an antagonist of P1 receptors, increased the stimulation-evoked release of acetylcholine, indicating that the release of acetylcholine is tonically controlled by endogenous adenosine via P1 receptors. When alpha,beta-methylene-ATP and 8-phenyltheophylline were added together, their potentiating effect on the acetylcholine release proved to be additive. Because alpha,beta-methylene-ATP failed to antagonize the presynaptic effect of adenosine on P1 purinoceptors, it seems very likely that its effect to enhance transmitter release is mediated via separate receptors, i.e., via P2x receptors, located on the axon terminals. Similarly, the stimulation-evoked release of [3H]noradrenaline was enhanced slightly by alpha,beta-methylene-ATP. Our results suggest that both cholinergic and noradrenergic axon terminals are equipped with P2 receptors through which the stimulation-evoked release of transmitter can be modulated by ATP in a positive manner.(ABSTRACT TRUNCATED AT 250 WORDS)

journal_name

J Neurochem

journal_title

Journal of neurochemistry

authors

Sperlagh B,Vizi ES

doi

10.1111/j.1471-4159.1991.tb02039.x

subject

Has Abstract

pub_date

1991-05-01 00:00:00

pages

1466-70

issue

5

eissn

0022-3042

issn

1471-4159

journal_volume

56

pub_type

杂志文章

相关文献

JOURNAL OF NEUROCHEMISTRY文献大全