Neurohormonal regulation of histamine and pancreastatin secretion from isolated rat stomach ECL cells

Ghrelin and gastric acid secretion

“…Gastrin stimulates acid secretion via enterochromaffin-like cells (ECL cell) [23] . Another transmitter, PACA, was also found to increase histamine release from ECL cell [24] . PACAP-immunoreactive nerve fibers are abundant in the gastric mucosa of both rat and humans [25] and gastric ECL cells possesses PACAP receptors(PAC1) [26] .…”

“…However, they concluded that histamine was not involved in the action of ghrelin on acid secretion, as famotidine did not inhibited ghrelin-induced acid secretion [10] . Tthe mechanism that was demonstrated by Masuda seemed to require further investigation, because the vagal stimulation [29] , as well as transmitter PACAP, is known to increase release of histamine from ECL cells [24] . Therefore, if ghrelin administration stimulates the vagal nerve, an increase in histamine release would consequently occur.…”

PACAP upsets stomach theory

“…However, cultured ECL cells have responded poorly to the M 1 agonist carbachol, raising the possibility that the effect of ACh is indirect, and precipitating a 10-year search for a suspected neural mediator. Pituitary adenylate cyclase-activating polypeptide (PACAP) has become an increasingly likely candidate since its recent identification in gastric enteric neurons (6) and the discovery of its ability to stimulate histamine secretion (7,8) and proliferation by ECL cells in culture (9). However, peripheral injection of PACAP has been shown to inhibit gastrin-stimulated acid secretion in vivo (10).…”

Pituitary adenylate cyclase activating peptide (PACAP) immunoreactivity and mRNA expression in the duck gastrointestinal tract

“…It should be remembered that PACAP has evident stimulatory effects on gastric acid secretion. Indeed, it elicits histamine release from enterochromaffin cells (Lindström et al 1997;Lindström and Håkanson 2001) by binding PAC1 receptors and also activating L-type calcium channels (Zeng et al 1999a(Zeng et al , 1999b.…”

“…Gastrointestinal PACAP has both an intrinsic and extrinsic origin (Portbury et al 1995;Hannibal et al 1998) and seems to be involved in the modulation of gastrointestinal motility, secretion and proliferation Lindström et al 1997; for a review, see Läuffer et al 1999).…”