PROTEIN-MALNUTRITION ALTERS THE CHOLINERGIC AND GABAERGIC SYSTEMS OF THE HIPPOCAMPAL-FORMATION OF THE ADULT-RAT - AN IMMUNOCYTOCHEMICAL STUDY

We attempted to find out if the cholinergic and GABAergic systems that regulate the hippocampal circuitries are disturbed after long periods of protein deprivation and, in the,affirmative, to investigate if the changes are reversible following nutritional rehabilitation. A group of 2 month old rats fed with a low-protein diet for 12 months was comp ared with age-matched controls and with nutritionally rehabilitated ra ts. We have evaluated the length density of the cholinergic fiber netw ork and estimated the numerical densities of the choline acetyltransfe rase and GABAergic immunoreactive neurons of the hippocampal formation . Our results show that prolonged malnutrition leads to a substantial, but reversible, reduction in the cholinergic innervation of the hippo campal formation and to an irreversible loss of hippocampal cholinergi c and GABAergic neurons.