Hippocampal long term potentiation in rats under different regimens of vitamin D: an in vivo study

Evidence indicates that vitamin D involves in development of brain as well as its function. This study assesses occurrence of long term potentiation (LTP), as an experimental form of synaptic plasticity, in adult rats under the normal regimen (CON), and the regimens without vitamin D (CON-D) or with a supplement of 1,25(OH)2D3 (CON+D). Stimulating the Schaffer collaterals pre- and post-tetanus excitatory postsynaptic potentials (EPSPs) were recorded in the CA1 area of hippocampus in anesthetized animals. Amplitude change of the EPSPs was considered for comparisons. Our results indicated that the basic EPSPs were similar in the three groups. Tetanization elicited a considerable LTP in both the CON and CON+D rats but a moderate potentiation in the CON-D group. We concluded that optimal level of vitamin D is required for induction of LTP.