On the enzymatic response to injury and its mediators

The enzymatic response to injury appears as an increase in enzymatic activity in the periphery of burns and other injuries. The following processes constitute the enzymatic response: 1) release, 2) activation and 3) synthesis of enzymes. Processes 2) and 3) are dependent upon the fibroblast, which is an activated fibrocyte. Among the fibrocyte activators, and thus among the mediators of the enzymatic response, are histamine, serotonin, kinins, prostaglandins etc. The effects of non-steroidal anti-inflammatory drugs on the enzymatic response to burn injury were studied. Indomethacin, mefenamic acid or aspirin, suspended in carboxymethylcellulose, were given to rats by stomach tube. Controls received carboxymethylcellulose only. Circular burns were inflicted on anaesthetized animals which were killed 30 min, 2 h or 4 h after burning. The burns were studied histologically and enzyme histochemically by using the methods for prostaglandin synthetase, esterases, and adenosine triphosphatase. Aspirin had no effect on the enzymatic response. Mefenamic acid and indomethacin caused a less severe enzymatic response in the 4-h groups as compared to control rats.