On the Mechanism of Bradykinin Potentiation

Reliable Evidence of Involvement of the Kinin System in Mouse Malaria

“…Concerning the determination method of kininogen, which was reported by Diniz and Carvalho (10) and was used in this experiments, recent papers reported the contami nation of bradykinin potentiator(s) besides released bradykinin after incubation of acidified, denatured plasma with trypsin (11,12). Since this was confirmed by' us and the improve ment of the method has not been established, attention was paid as described in the me thods of the present paper.…”

“…Kinin in 0.05 ml of sample dissolved in 4 ml of Munsick solution was assayed on the rat uterus. Recently, it was reported that the method also produced potentiator(s) of bradykinin (11,12). Although this was confirmed in our laboratory (to be published), kininogen deter mination in these experiments was performed by the original method with the following special attentions: The Volume of Munsick solution requried to dissolve dried residues and samples to be put into the organ bath was restricted to 4 ml and 0.05 ml respectively.…”

Inhibition of human peptidyl dipeptidase (angiotensin I converting enzyme: kininase II) by human serum albumin and its fragments.

“…Albumin present in partially purified human CE preparation may account for the low CE activity of these preparations. Digests of serum proteins can also inhibit other enzymes that inactivate bradykinin such as pancreatic carboxypeptidase B, 28 a very potent kininase. Our experiments have shown that albumin and its fragments inhibit CE noncompetitively, without being substrates of the enzyme.…”

Bradykinin-potentiating peptides from the venom of Agkistrodon halys. Isolation of five bradykinin potentiators and the amino acid sequences of two of them, potentiators B and C

“…Sulfhydryl compounds which have bradykinin-potentiating activity, inhibited plasma kininases (Ferreira and Rocha e Silva, 1962). A bradykinin-potentiating peptide, isolated from human plasma after digestion with trypsin, was found to have arginine or lysine as its C-terminal amino acid, and it competitively inhibited the activity of carboxypeptidase B with bradykinin-destroying activity (Hamberg et al, 1969). Yang et al (1970) reported that one of the kininases in human plasma seemed to be identical with the angiotensin-converting enzyme.…”

“…e-Aminocaproic acid (Doleschel and Auerswald, 1966), a tryptic hydrolysate of denatured human plasma (Aarsen, 1968), an extract of pig liver (Tewksbury and Stahmann, 1965), and products of degradation of fibrinogen by plasmin (Buluk and Malofiejew, 1969) also have bradykinin-potentiating activity. Hamberg et al (1969) attempted to isolate bradykinin-potentiating peptides from a tryptic hydrolysate of human plasma and a plasmic hydrolysate of human fibrinogen, and found that the bradykinin-bradykinin-potentiating activity on guinea pig ileum. On the other hand, only potentiator E showed high bradykininpotentiating activity on rat uterus, the other four peptides having very slight activity.…”