The effect of some exogenous factors on the formation of intranuclear membranaceus inclusions in the nerve cells.

The intranuclear membranaceus inclusions (IMI) appear as encapsulated irregular vacuoles surrounded by a single, rarely double, membrane. The vacuoles include floccular, fine granular content or they are translucent. They were found in neurones of particularly old or very young laboratory animals. Our studies concerning various types of intoxications and ischemia allowed to find relatively large number of such inclusions in laboratory animals. We observed them in four experimental models: (1) cyclo-phosphamide (an alkylating drug) and (2) dichlorvos (phosphoroorganic pesticide) given orally to rabbits, (3) complete ischemia also in rabbits and (4) vincristine (an antimitotic drug) given parenteraly to rats. The IMI were found much more frequently in experimental animals than in controls. We can conclude that intranuclear membranaceus inclusions do not appear to be pathognomonic for any particular etiologic factor, but this factor may influence and distort the homeostasis within nucleus.