PRENATAL DIETARY CHOLINE SUPPLEMENTATION DECREASES THE THRESHOLD FOR INDUCTION OF LONG-TERM POTENTIATION IN YOUNG-ADULT RATS

Choline supplementation during gestation in rats leads to augmentation of spatial memory in adulthood. We hypothesized that prenatal (E12-E1 7) choline supplementation in the rat would lead to an enhancement of hippocampal synaptic plasticity as assessed by long-term potentiation (LTP) at 3-4 mo of age. LTP was assessed blindly in area CA1 of hippoc ampal slices with first suprathreshold (above threshold for LTP genera tion in control slices) theta-burst stimulus trains. The magnitude of potentiation after these stimuli was not different between slices from control and prenatally choline supplemented animals. Next, threshold (reliably leading to LTP generation in control slices) or subthreshold theta-burst stimulus trains were applied to slices from control, pren atally choline-supplemented, and prenatally choline-deprived rats. Thr eshold level stimulus trains induced LTP in slices from both the contr ol and choline-supplemented rats but not in those from the choline-def icient rats. Subthreshold stimulus trains led to LTP induction in slic es from prenatally choline-supplemented rats only. These observations indicate that prenatal dietary manipulation of the amino acid, choline , leads to subsequent significant alterations of LTP induction thresho ld in adult animals.