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)

Cholecystokinin (CCK) binding to its receptors on guinea pig gastric chief cell membranes was characterized with 125I-COOH terminal octapeptide of CCK (125I-CCK8). Specific binding of 125I-CCK8 to chief cell membranes was maximal at pH 6.0 and 30 degrees C after 180 min of incubation and reversible upon the addition of 10(-7) M unlabeled CCK8. CCK analogs such as CCK8, gastrin-I, and COOH-terminal tetrapeptide of CCK (CCK4) competitively inhibited the labeled CCK8 binding with the half maximal inhibitory concentration of 10(-10) M, 3 X 10(-7) M and 10(-6) M, respectively. Furthermore, guanine nucleotide analogs such as GTP gamma S and Gpp(NH)p also inhibited the labeled CCK8 binding to chief cell membranes. Scatchard analysis of the binding data at pH 6.0 revealed two orders of the binding sites and GTP gamma S decreased the binding by converting two binding sites of the receptors to only one site of lower affinity. These results suggest that there are specific receptors for CCK, which are coupled to a guanine nucleotide regulatory protein on guiea pig gastric chief cell membranes.
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PMID:[Cholecystokinin receptors on guinea pig gastric chief cell membranes]. 212 47

The neuro-intestinal peptide hormone cholecystokinin (CCK)/gastrin has been suggested to have a trophic effect on gastro-intestinal tract in vivo as well as in vitro. In the present study, the human CCK-B/gastrin receptor was expressed in mouse NIH3T3 fibroblasts to investigate the molecular basis of signal transduction pathway of the guanine nucleotide regulatory protein (G protein)-coupled receptor. Human CCK-B/gastrin receptor expressed in NIH3T3 cells coupled efficiently to phosphoinositide hydrolysis and mobilization of intracellular Ca2+, and transduced mitogenic signals assessed by [3H]thymidine incorporation in a dose-dependent manner. Moreover, CCK-8 or gastrin I alone promoted the cell growth in serum-free medium. CCK-8 induced tyrosine phosphorylation of several protein species. Among them, mitogen-activated protein (MAP) kinase was tyrosine phosphorylated and activated in response to CCK-8, as was induced by platelet-derived growth factor (PDGF). In contrast, tyrosine phosphorylation of p125FAK (focal adhesion kinase) was induced by CCK-8 but not by PDGF. CCK-8 as well as gastrin I induced the expression of early responsive genes such as c-fos and c-myc. These results suggest that CCK-B/gastrin receptors might transmit mitogenic signals by cross-talking with the tyrosine kinase cascades.
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PMID:Cholecystokinin-B/gastrin receptor signaling pathway involves tyrosine phosphorylations of p125FAK and p42MAP. 810 29