Biochemical studies have shown that antimitotic doses of colchicine (1.5 mg./kg.) produce a decrease in lactic dehydrogenase (LDH) and an increase in lysosomal enzyme activity in mouse intestinal mucosa. Administration of these large doses of colchicine evidently causes cellular death, with inflammatory response.
Small doses of colchicine (0.24 mg./kg.), while decreasing LDH activity in the intestinal mucosa, did not significantly change
-glucuronidase activity and, as verified histologically, did not produce cell destruction, or inflammatory reaction. Puromycin administered to mice did not affect the LDH activity in the intestinal mucosa at 60 hr. after administration. One can therefore presume that the effect of colchicine on LDH activity is not secondary to inhibition of protein synthesis. The inhibitory effect of colchicine on LDH and other enzyme systems may be independent of colchicine action on the mitotic apparatus, and certainly precedes it.
Supported by Grants AM 08541, CA 04980, and 2A 5286 from the U. S. Public Health Service.
Trainee under Gastroenterology Training Grant TI AM 5286 from the U. S. Public Health Service.