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PubMed · 7030634

Protease activities in human tears.

P K Tsung·F J Holly
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Abstract

Several protease activities were measured in human tears by six specific substrates. The specific activity of cathepsin B-like enzyme was 7-fold higher in Orientals than in Caucasians. The trypsin-like and cathepsin C-like enzyme activities also showed 3 to 4-fold higher in Orientals than in Caucasians. However, the deviation in the activities of these two enzymes was high in both Orientals and Caucasians. Similar results were obtained when comparing the protease activities of tear collected by glass capillary and a filter-paper strip method. Since a surface-active small molecular weight fraction can be produced by incubation of freshly collected tears for 4 hours at 37 degrees C, the low molecular weight surfactant may be a proteolytic product.

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Asian PeopleCathepsinsHumansPeptide HydrolasesSurface-Active AgentsTearsWhite PeopleJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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P K Tsung, F J Holly. 1981. Protease activities in human tears.. https://doi.org/10.3109/02713688108998361

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