Prenatal choline deficiency decreases the cross-sectional area of cholinergic neurons in the medial septal nucleus.

Levels of dietary choline in utero influence postnatal cognitive performance. To better understand this phenomenon, forebrain cholinergic neurons were studied in the 8-9 month old offspring of dams fed a control or choline-deficient diet from EDs 11-17. Serial sections were immunostained with antibodies against p75, a cholinergic marker. Neuronal morphology was analyzed in the basal forebrain, a heterogeneous area composed of several structures including the medial septal nucleus (MSN), nucleus of the diagonal band (DB), and the nucleus basalis of Meynert (NB). Neuronal cross-sectional areas were selectively reduced in the MSN of choline-deficient animals, compared to controls, but cell counts were not altered. Our findings suggest that cholinergic medial septal neurons may be selectively vulnerable to in utero choline deficiency.