Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The organophosphate diisopropylfluorophosphate (DFP; 3 or 6 mg/kg, IP) caused a dose-related antinociception in mice which was antagonized by the muscarinic antagonist scopolamine. The opiate antagonist naloxone antagonized the antinociceptive effect of the highest dose of DFP, but did not affect the antinociception caused by 3 mg/kg DFP. Twenty-four hours after the administration of DFP, reaction time in animals which received a 3 mg/kg dose did not differ from control. However, reaction time was still significantly higher than control in mice administered 6 mg/kg DFP twenty-four hours earlier. This residual antinociception was antagonized by naloxone but not by scopolamine, suggesting that it was opioid in nature. These results suggest that antinociception induced by a low dose of DFP is primarily due to a cholinergic mechanism, while higher doses appear to affect also the opiate system. Since we have previously shown that DFP (6 mg/kg) increases met-enkephalin levels in brain, it is possible that high doses of DFP might interfere with enkephalin metabolizing enzymes. This conclusion cannot be extended to the organophosphate disulfoton, whose antinociception, even at high doses, appears to involve only an interaction with the cholinergic system.
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PMID:Cholinergic and opiate involvement in the antinociceptive effect of diisopropylfluorophosphate. 301 Mar 40

Two distinct dipeptidyl aminopeptidases, which were designated DPP-A and DPP-B, were purified from soluble fraction of monkey brain using Leu-enkephalin as the substrate. The enzymes were purified 187 and 136 fold, respectively. Both enzymes showed the optimum pH in neutral range. Their molecular weights were almost equal and were estimated to be about 100,000. Their Km values with Leu-enkephalin as the substrate were 5.6 X 10(-5) and 1.1 X 10(-5) M, respectively. Among synthesized substrates, the highest affinity of the enzymes was toward arginyl-arginine beta-naphthylamide with the Km values of 6.25 X 10(-5) and 6.41 X 10(-5) M, respectively. Both enzyme activities were inhibited by the metal-chelators DFP and PCMB. Two hundred fifty microM arphamenine A inhibited DPP-A and -B with inhibition of 36.6% and 44.1%, respectively. Beta-endorphin, ACTH, and glucagon inhibited only DPP-B, while beta-lipotropin and angiotensin II inhibited both DPP-A and -B when Leu-enkephalin was used as the substrate.
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PMID:Purification and characterization of two distinct dipeptidyl aminopeptidases in soluble fraction from monkey brain and their action on enkephalins. 637 97