Effect of colchicine on carrageenin-induced granulomatous inflammation in rats.

Abstract

The effect of colchicine on inflammatory responses in chronic, proliferative inflammation was investigated by using 8-day-old granuloma pouch induced with carrageenin in rats. Colchicine was injected directly into the granuloma pouch, and then vascular permeability of the granuloma pouch, blood volume in the granulation tissue and incorporation of 3H-proline into non-collagen protein of the granulation tissue were determined. Vascular permeability was assayed with the aid of radioiodinated human serum albumin as a tracer. The volume of the blood in the granulation tissue was also measured by using radioiodinated human serum albumin. In the early stage in the action of colchicine, it induced enhancement of the vascular permeability in the granulation tissue, and then, it induced suppression in the late stage in its action. The blood content of the granulation tissue did not change in the early stage but lowered in the late stage in advance to the suppression of the vascular permeability. Therefore, the most primary action of locally injected colchicine is to raise the vascular permeability in the local tissue, and then to decrease blood volume in the local tissues with resultant suppression of the vascular permeability. Incorporation of labeled proline into tissue protein was suppressed under the influence of colchicine regardless of its effect on the vascular permeability.