Portal de Periódicos da CAPES

Trypsin Inhibitors in Guinea Pig Plasma: Isolation and Characterization of Contrapsin and Two Isoforms of α -1-Antiproteinase and Acute Phase Response of Four Major Trypsin Inhibitors

1990; Oxford University Press; Volume: 107; Issue: 2 Linguagem: Inglês

10.1093/oxfordjournals.jbchem.a123021

1756-2651

Yasuyuki Suzuki, Kōji Yoshida, Toshihide Ichimiya, Tetsuya Yamamoto, Hyogo Sinohara,

Biochemical and Structural Characterization

Contrapsin and two isoforms, F (fast) and S (slow) of α -1-antiproteinase (also called α -1-proteinase inhibitor) were isolated in an apparently homogenous state from plasma of inflamed guines pigs. Contrapsin insctivated trypsin, but did not significantly affect chymotrypsin, pencreatic elastasee, or pancreatic kallikrein. On the other hand, both isoforms of α -1-antiproteinase inhibited trypsin, chymotrypsin, and elastase, but not plasma or pancreatic kallikrein. The S isoform of α -1-antipreteinase was present in barely detectable amounts inhealthy animals, but increased markedly when the acute-phase reaction was induced b y subcutaneous injection of turpentine. On the other hand, the plasma levels of the F isoform, contrapsin, and α -macroglobulin showed moderate (1.5 to 2.3-fold) elevation during the acute-phase reaction. In contrast to the previous findings that rats and rabbits contain two different α -macroglobulins, one of which is an acute-phase reactant while the other is not, inflamed guines pigs contained only one species of α -macroglobulin. Murinoglobulin, the most prominent acute-phase negative protein in both mice and rats, showed no significant change in guines pits. These results indicate that guinea pig plasma contains four major trypsin inhibitors, i. e., contrpasin, α -1-antiproteinase, α -macroglobulin, and murinoglobulin, the properties of which are very similar to those fo the respective mouse homologues, but that the acute-phase response of these inhibitors differs greatly from that of the homologous proteins in rate or mice.