Effect of colchicine on heart lipoprotein lipase

Changes in heart lipoprotein lipase (LPL) activity provoked by colchicine (0.5 mg/100 g body weight) and heparin (10 IU/100 g body weight) were studied in heart homogenates and serum from rats treated with both drugs or with heparin alone. In addition experiments were carried out in vitro in which the action of colchicine alone and colchicine plus heparin was compared with controls. In vivo experiments showed that colchicine decreased post-heparin release of the enzyme in fed animals, but was incapable of doing so in fasted animals. Accordingly, heart LPL activity, expressed in percentage of control values, did not change in fed animals, but significantly decreased (p less than 0.05) in fasted animals. In the in vitro experiments, colchicine significantly decreased heart LPL activity (p = 0.025) whether or not heparin was present and regardless of the nutritional state of the rats. Apparently, colchicine has two distinct actions on heart LPL activity: a direct one on the enzyme and another mediated by the nutritional state of the animal.