<div>Background: Acetylcholinesterase (AChE) is an enzyme belonging to hydrolase group which splits the acetylcholine in to choline and acetate. It is supposed to be a marker of cholinergic and cholinoceptive neurons. Acetylcholinesterase histochemisry has been done in a number of vertebrates but it is still obscure and scattered in fishes, particularly in Indian fishes.&nbsp; 
 
Methods: In the present study a modified histochemical technique has been employed to histochemically map the acetylcholinesterase containing neurons in the telencephalic and diencephalic nuclei of C. punctatus described by Hedreen, et al (1985). 
 
Result: Acetylchoinesterase is differentially expressed in the various prosencephalic centres and nuclei of the brain, thus its staining clearly demarcates these centres and nuclei based on varying enzyme intensity. Among the pallial nuclei of the forebrain, medial and dorsolateral nuclei showed intense enzyme activity while ventral dorsolateral nucleus and central nucleus showed moderate reaction. In contrast, most of the subpallial nuclei of the forebrain showed high intensity. Diencephalic nuclei of the forebrain exhibited mosaic pattern of enzyme distribution.&nbsp;</div>

Histochemical Distribution of Acetylcholinesterase in the Forebrain Nuclei of an Indian Non Catfish Channa punctatus