PROTECTIVE EFFECT OF STEM BROMELAIN AGAINST ADRENALINE PULMONARY EDEMA, AND ITS DEPENDENCE ON THE PROTEOLYTIC ACTIVITY

It was reported previously that pretreatment of rats with a crude preparation of stem bromelain, a thiolprotease obtained from pineapple plant, effectively protected the animals against adrenaline-induced pulmonary edema (1-3). The present study was undertaken to examine whether the edema-preventive effect of the enzyme is due to its proteolytic activity. For this purpose, purified and activated stem bromelain was prepared. A part of this was then inactivated by N-ethylmaleimide, a specific SH-inhibitor. The edema-preventive effects of the two enzyme preparations were compared.