[Ultrastructural changes in the wall and microcirculatory bed of the small intestinal villi of rats exposed to organochlorine toxicant].

Male Wistar rats were administered 60 mg/kg of organochlorine pesticide 2,4-D daily (two permissible daily doses) for 2.5 months in order to develop an experimental model of chronic intoxication. It was found that the long term administration of organochlorine toxicant resulted in marked structural changes in both the cells of the wall of small intestine and in lymphatic and blood capillaries of the villi (distention of the rough endoplasmic reticulum cisterns, reduction of the number of mitochondrial christae, increase in the secondary lysosomal content, reduction of the number of micropinocytotic vesicles).