title: Purification and inhibition by neuropeptides of angiotensin-converting enzyme from rat brain.
abstract: Angiotensin-converting enzyme was solubilized with papain from a particulate fraction of rat brain and purified to apparent homogeneity by a procedure including DEAE-cellulose, hydroxylapatite, Sephadex G-200, Cys(Bzl)-Pro-Sepharose, and ricin-Sepharose chromatography. Bradykinin potentiators, SQ 14,225, and Arg-Pro-Pro strongly inhibited the activity of the purified enzyme, whereas Phe-Ala, phosphoramidon, and pentobarbital exerted little inhibitory effect on the activity. Among neuropeptides investigated, substance P, bradykinin, and Leu-enkephalin (Arg6) exerted strong inhibitory actions on the enzyme. Furthermore, the latter two peptides were shown to be good substrates for the enzyme. Thus, angiotensin-converting enzyme of rat brain is distinct from endogenous enkephalinase and may interact with various neuropeptides located in the brain.
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors; D000818:Animals; D001920:Bradykinin / Q000494:pharmacology; D001921:Brain / Q000201:enzymology*; D004743:Enkephalin, Leucine / Q000494:pharmacology; D004744:Enkephalin, Methionine / Q000494:pharmacology; D007700:Kinetics; D009419:Nerve Tissue Proteins / Q000494:pharmacology*; D010206:Papain; D007703:Peptidyl-Dipeptidase A / Q000302:isolation & purification; D051381:Rats; D012995:Solubility; D013373:Substance P / Q000494:pharmacology
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D009419:Nerve Tissue Proteins; D013373:Substance P; D004744:Enkephalin, Methionine; D004743:Enkephalin, Leucine; D007703:Peptidyl-Dipeptidase A; D010206:Papain; D001920:Bradykinin