Alterations in the activity of tissue and plasma
kallikreins and in the levels of their precursors in rabbit lacrimal fluid were studied after alkaline
burn of the cornea and treatment with
hordox. The enzymatic activity was measured using the
fluorogenic substrate Z-Phe-Arg-MCA. The activity of
plasma kallikrein was increased in the lacrimal fluid within the first week after
burn. Unlike
plasma kallikrein,
tissue kallikrein showed a higher activity within 14 and 28 days. The maximal increase in the levels of plasma and
tissue kallikreins occurred within the first week. Subconjunctival
injections of
hordox, 0.3 ml (30,000 kIU), daily within 10 days led to a decrease in the activity of either
kallikrein within the first week and did not alter
tissue kallikrein activity within 14 and 28 days.
Hordox did not affect the content of prekallikreins. The activation of
tissue kallikrein at days 14-28 appears to occur due to increased proliferation and served as protective and compensatory responses; treatment with the polyvalent inhibitor of
proteinases hordox within 8-10 days after
burn did not affect this function of
tissue kallikrein.