Effect of aflatoxicosis on acetylcholinesterase activity in the brain and adenohypophysis of the male rat.

The effects of 7 or 42 48-hourly i.p. injections of 20 micrograms aflatoxin B1 (AFB) on the acetylcholinesterase activity (AChE) in 8 brain areas and the adenohypophysis of the adult male rat were studied. Aflatoxicosis increased adenohypophysial AChE in direct proportion to the duration of intoxication, which also altered the distribution of AChE in the rat brain. With acute treatment, AChE was depressed in the cerebellum and hippocampus while in the chronically dosed rats AChE was drastically elevated in the mesencephalon and amygdala. Results suggest that AFB changes the ACh turnover and hence the cholinergic transmission in the brain and adenohypophysis. This may result in behavioural deficits and/or performance decrements via a disturbance of the hypothalamo-hypophysial axis.