Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.11.11 (AMPK)
 12,425 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Stimulatory effects of Ca2+-CaM and PKI on partially purified hypothalamic HD (10 fold purification) have been shown under conditions involving inhibition of the enzyme by cAMP-induced phosphorylation and under control conditions. A 1:1 (v/v) mixture of 0.1 mM CaCl2 and 10 units of CaM from human red blood cells reversed the inhibition of HD induced by cAMP-dependent protein phosphorylation activity to the control level. Verapamil (0.01 mM) could partially block the former effect without affecting the control level of enzyme activity. 0.01 mM TPA did not further increase the effect of Ca2+-CaM on HD, in the presence of 0.01 mM ATP, indicating that this stimulation does not require the action of Ca2+-dependent protein kinase. The control level of HD is not influenced by 0.1 mM CaCl2 or 0.02 mM EGTA but is raised by CaM in the presence of CaCl2 (0.1 mM). A highly purified protein kinase (cAMP-dependent) inhibitor (PKI) from bovine heart and a crude inhibitor from rat cerebellum could also reverse the inhibitory effect of cAMP-dependent protein kinase under phosphorylating conditions and enhanced HD activity above control levels. PKI and Ca2+-CaM, added together, produced single, not additive effects. We conclude that cAMP-induced phosphorylation is probable the main regulatory mechanism of histamine formation and this could be influenced by both Ca2+-CaM and PKI. Inhibition of cAMP-dependent protein kinase as well as stimulation of phosphoprotein phosphatase and Ca2+-CaM-dependent phosphodiesterase might be involved in the above actions.
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PMID:Stimulation of hypothalamic histidine decarboxylase by calcium-calmodulin and protein kinase (cAMP-dependent) inhibitor. 360 3

In dispersed acini from rat pancreas, verapamil (a phenylalkylamine calcium channel blocker) potentiated amylase secretion stimulated by vasoactive intestinal peptide (VIP), secretin, peptide histidine isoleucine, helodermin, forskolin, and 8-bromocyclic AMP. The action of verapamil on VIP-stimulated amylase secretion was detectable at 10 microM verapamil and maximal at 100 microM verapamil. Verapamil did not alter binding of 125I-VIP, basal cAMP, the increase in cAMP caused by VIP, or the increase in cAMP-dependent protein kinase caused by VIP. The effects of verapamil on stimulated amylase secretion were fully reversible and could be reproduced by nicardipine (a 1,4-dihydropyridine calcium channel blocker) and diltiazem (a benzothiazepine calcium channel blocker), but not by cinnarizine (a piperazine calcium channel blocker). Although 300 microM verapamil increased outflux of 45Ca, 100 microM verapamil, the concentration that produced maximal potentiation of VIP-stimulated amylase secretion, did not alter 45Ca outflux. Our results indicate that the action of verapamil to potentiate amylase secretion stimulated by secretagogues that activate the cAMP pathway occurs at a step that is distal to the activation of cAMP-dependent protein kinase.
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PMID:Effect of verapamil on the cyclic AMP-mediated pathway for amylase secretion in rat pancreatic acini. 768 80

Shear stress can modulate endothelial cell function by regulating gene expression. We have previously demonstrated that low shear stress (4.2 dyn/cm(2)) induces the expression of interleukin-8 (IL-8) gene in endothelial cells. The present study was undertaken to further investigate both the effects of shear stress on IL-8 expression and the mechanisms controlling IL-8 mRNA up-regulation in human umbilical vein endothelial cells (HUVEC). We show that shear stress (from 2.23 to 19.29 dyn/cm(2)) induces the IL-8 expression at both the mRNA and protein levels by stimulating transcription. In order to determine the possible contribution of G protein, HUVEC were pretreated with an inhibitor of G-protein activation, GDPbetaS, which abrogated the low shear stress-induced IL-8 gene expression. Such gene expression was also partially inhibited by the tyrosine kinase inhibitor (tyrphostin-25) and in addition by EGTA, BATPA/AM (the intracellular Ca(2+) chelator), Verapamil (a Ca(2+) channel blocker), cAMP-dependent protein kinase inhibitor (KT5720) and phospholipase C inhibitor (neomycin). However, the cGMP-dependent protein kinase inhibitor, KT5823, had no effect on such expression. These findings therefore demonstrate the involvement of several signaling molecules, including tyrosine kinase, G protein, calcium, phospholipase C, and cAMP-dependent protein kinase, in the low shear stress-induced IL-8 gene expression.
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PMID:IL-8 gene induction by low shear stress: pharmacological evaluation of the role of signaling molecules. 1855 29