Experimental Emphysema in Guinea Pig II. Studies on lung antiprotease in guinea pig

• Published in: The Japanese journal of thoracic diseases Vol. 17; no. 3; pp. 152 - 160
• Main Author: Miyazaki, Nobuyoshi
• Format: Journal Article
• Language: English
• Published: The Japanese Respiratory Society 25.02.1979
• ISSN: 0301-1542; 1883-471X
• DOI: 10.11389/jjrs1963.17.152

Morphologic studies on elastase-induced emphysema have been reported previously. The purpose of this paper was to report the characteristics of lung protease inhibitor in the guinea pig and to partially purify this substance. The role of lung antiprotease obtained from the lung lavage of guinea pig, protease inhibitory capacity and inhibition of experimental emphysema were defined. Furthermore, an attempt was made to separate this lung antiprotease and to clarify the nature of it. The following results were obtained: 1) SLAPN is more sensitive and more specific than previous synthetic substrates as NBA. Activity against elastin-agar plates was only detectable in elastase, whereas the elastolytic activity of papain was not detectable on elastin-agar plates and SLAPN. 2) Lung inhibitor in the lung lavage of guinea pig showed elastase inhibitory activity and also inhibited the induction of experimental emphysema by elastase. On the other hand, trypsin inhibitory activity was not detectable in this material. 3) The molecular weight of the lung inhibitor was determined to be about 60000 by gel filtration. Activities of the lung inhibitor were unstable against heating and acid. Partial purification increased the elastase inhibitory activity about twenty-two-fold following affinity chromatography using Sepharose 4B-elastase column.