Evidence for an involvement of eicosanoids in neurokinin3-receptor mediated acetylcholine release from myenteric neurons.

The release of acetylcholine (ACh) from myenteric plexus evoked by 5-hydroxytryptamine (5-HT) and senktide (a selective neurokinin3 (NK3) agonist) was depressed by mepacrine, an inhibitor for phospholipase A2 activity. Release of ACh was stimulated by arachidonic acid; this release was partially depressed by nordihydroguaiaretic acid (NDGA), which inhibits lipoxygenase activity. NDGA failed to modify the ACh secretion elicited by 5-HT. Release of ACh evoked by senktide was significantly inhibited by NDGA, suggesting an involvement of eicosanoids in the release of ACh elicited by specific neurokinin receptors in myenteric neurons.