Effects of Subcutaneous Postnatal Choline Supplementation on Hippocampus-Mediated Learning and Memory in Rat Pups

by Moore, Jeremy Alan

The effects of postnatal injections of choline on the acquisition of two variants of eyeblink conditioning were examined in developing Long-Evans rat pups. Choline administration on postnatal days (PND) 15-27 was followed by evaluation of trace eyeblink conditioning (Experiment 1) and delay eyeblink conditioning (Experiment 2) on PND 28-29. The results of these experiments show that choline produced greater improvements in learning and memory during the trace condition than in the delay condition, presumably due to its effect on the hippocampus. Trace eyeblink conditioning relies heavily on an intact hippocampus but delay eyeblink conditioning does not, and it is understood that choline has a positive influence on hippocampal function. This was the first study to examine the effects of choline on eyeblink conditioning and provides baseline data for future research into the beneficial effects of choline for this type of learning as well as its potential neuroprotective effects for the hippocampus.