title: Some components of the kinin system in Cohn's unheated human plasma proteins.
abstract: The presence of a kininase and a kininogenase was demonstrated in unheated human plasma proteins. The kininase was found to inactivate synthetic bradykinin and a kinin-like substance released from a kininogen-like material in unheated plasma proteins by human urinary kallikrein. It was heat-labile and inhibited by EDTA, HgCl2 and 1,10-phenanthroline. This enzyme was estimated to be kininase I from its inhibition pattern. Inactivation of the kininase revealed the presence of a kininogenase. Five per cent heat-treated human plasma protein solution has been demonstrated to have no kininase activity but to contain the kinin-like substance. A mechanism for the formation of the kinin-like substance in 5 per cent heat-treated plasma protein solution was discussed in terms of these kinin forming components present in the unheated plasma proteins.
mesh_terms: D001798:Blood Proteins / Q000032:analysis*; D001920:Bradykinin; D004492:Edetic Acid / Q000494:pharmacology; D006358:Hot Temperature; D007610:Kallikreins / Q000097:blood / Q000652:urine; D007705:Kinins / Q000097:blood*; D001121:Lysine Carboxypeptidase / Q000037:antagonists & inhibitors / Q000097:blood; D008628:Mercury / Q000494:pharmacology; D009119:Muscle Contraction; D010618:Phenanthrolines / Q000494:pharmacology
chemical_list: D001798:Blood Proteins; D007705:Kinins; D010618:Phenanthrolines; D004492:Edetic Acid; D001121:Lysine Carboxypeptidase; D007610:Kallikreins; D008628:Mercury; D001920:Bradykinin