Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01350 (gastrin)
 9,683 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Intracellular recordings of membrane potential and input resistance have been made in vivo and in vitro from the exocrine acinar cells of rat pancreas using indwelling glass micro-electrodes. 2. The resting cell membrane potential and input resistance in the in vivo experiments were not markedly different from the values obtained in the in vitro experiments. The effect of both acetylcholine (ACh) and pancreozymin (CCK-Pz) on the pancreas in vivo as well as in vitro was to reduce both the acinar cell membrane potential and the input resistance narkedly. The amplitude of the evoked depolarization and the change in input resistance evoked by supramaximal stimuli were of the same magnitude in both types of preparations. 3. Gastrin had an effect on the acinar cell potential and resistance which was indistinguishable from that of CCK-Pz or ACh. The effect of gastrin or CCK-Pz was, in contrast to that of ACh, not influenced by the presence of atropine. The reversal potential for the gastrin evoked potential change was about -20 mV. 4. Secretin in doses producing maximal volume secretion in vivo had no effect on acinar cell membrane potential and input resistance. 5. Dibutyryl cyclic AMP (5mM) and cyclic GMP (1mM) had no effect on cell membrane potential or resistance. 6. It is concluded that the in vitro superfused pancreas segment preparation is a useful model system in electrophysiological studies since it functions essentially as the in vivo preparation. In contrast to both gastrin and CCK-Pz, secretin has no effect on the bioelectrical properties of the acinar cells, indicating that there are no physiologically important secretin receptors in rat acinar cells.
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PMID:Pancreatic acinar cells: effect of acetylcholine, pancreozymin, gastrin and secretin on membrane potential and resistance in vivo and in vitro. 16 55

Intracellular recordings from cultured parietal cells of the rat gastric fundus showed that carbachol, pentagastrin, histamine (in the presence of isobutylmethylxanthine; IBMX) and dibutyryl cyclic AMP induced hyperpolarizing responses which were sensitive to a K+ channel blocker, quinine. The Ca2+ ionophore, ionomycin, also induced a quinine-sensitive hyperpolarization. Deprivation of extracellular Ca2+ preferentially inhibited the hyperpolarizing responses to histamine (plus IBMX) and to dibutyryl cyclic AMP. Caffeine, oxalate and dantrolene sodium, which are known to affect Ca2+ transport in the endoplasmic reticulum, selectively inhibited the carbachol response. Mitochondrial inhibitors (KCN and carbonylcyanide p-trifluoromethoxyphenylhydrazone) preferentially suppressed the gastrin response. Cytosolic Ca2+ measurements with fura-2 indicated that significant increases in the intracellular concentration of free Ca2+ were induced not only by Ca2+-mediated acid secretagogues (carbachol and gastrin), but also by a cyclic AMP-mediated secretagogue (histamine plus IBMX). Dibutyryl cyclic AMP also increased cytosolic Ca2+ ions. It is concluded that stimulation of receptors to histamine, carbachol and gastrin gives rise to mobilization of Ca2+ ions into the cytoplasm from the different sources, thereby stimulating Ca2+-activated K+ channels in cultured rat parietal cells.
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PMID:Acid secretagogues induce Ca2+ mobilization coupled to K+ conductance activation in rat parietal cells in tissue culture. 275 38

We and others have recently reported an involvement of calcium (Ca2+)-mediated intracellular pathways in the release of antral gastrin in response to bombesin (BBS), while cyclic adenosine 3'5'-monophosphate (cAMP) potentiated the gastrin response to BBS. In this study we examined the effect of cyclic nucleotides on BBS-induced gastrin release from isolated perfused rat stomachs. Dibutyryl cyclic AMP (dbcAMP, 1 mM), and Rolipram (a phosphodiesterase inhibitor, 0.5 microM), stimulated basal gastrin secretion and potentiated BBS-induced gastrin release. The stimulation of gastrin release by BBS was not altered by Wiptide (a cAMP dependent protein kinase inhibitor, 1.0 microM), but was surprisingly inhibited by dbcGMP (1 mM). The cAMP content in antral mucosa or in the perfusates was not changed after infusion of BBS. These findings coupled with previous results suggest that BBS-provoked gastrin release is principally coupled to a Ca2+-mediated intracellular pathway, and that an activation of the adenylate cyclase mediated pathway is not involved. Intracellular cGMP, however, may participate in the negative regulation of gastrin release induced by BBS.
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PMID:Effect of cyclic nucleotides on bombesin-evoked gastrin release from isolated perfused rat stomach. 284 54