Choline acetyltransferase (ChAT), the enzyme responsible for the formation of ACh from choline and acetyl-coenzyme A, is a marker of cholinergic function and is significantly depressed in the brains of Alzheimer patients. It has been shown that omental tissue contains several neuroactive substances and causes revascularization when placed upon the brain of stroke patients. In this study, it was demonstrated that omental tissue exhibits specific ChAT activity. This activity was choline-dependent, inhibited by N-ethylmaleimide (a known ChAT inhibitor), and was characterized by kinetic parameters consistent with values for the neuronal enzyme. It is suggested that omental placement to the brain together with oral choline administration might prove to be useful for increasing ACh synthesis in Alzheimer's disease.