Objective    To study the effect of vitamin A deficiency during pregnancy on N-methyl-D- aspartate (NMDA)-induced Ca

2+

influx of hippocampal neurons in newborn rats.     Methods    Sixteen healthy male Wistar rats were randomly

divided into vitamin A deficiency group (n=8) and normal vitamin A group (n=8)

and fed with vitamin A deficient breed and vitamin A sufficient breed

respectively

3 weeks before copulation. Serum vitamin A level was measured by high performance liquid chromatography. Changes of Ca

2+

in primarily cultured hippocampal neurons of newborn rats were detected with a calcium imaging detector after treatment with NMDA. Expression of NMDA receptor 1 in hippocampus was detected by Western blotting.     Results    The serum vitamin A level was lower in vitamin A deficient group than in vitamin A sufficient group of mother and newborn rats [(0.768±0.069)μmol/L and (0.806±0.092)μmol/L vs (1.284±0.217)μmol/L and (1.270±0.098) μmol/L

P0.01

]

. Immunofluorescence showed no significant difference in neuron-specific enolase (NSE)

between the 2 groups. The ratio of hippocampal neurons was lower in vitamin A deficient group than in vitamin A sufficient group after treatment with NMDA [(0.136±0.012) vs (0.168±0.022)

P0.01

]

. Western blot analysis showed that the expression level of NMDA receptor 1 was significantly lower in vitamin A deficient group than in vitamin A sufficient group[(2.527±0.245) vs (1.157±0.197）

P0.05

]

.     Conclusion    Vitamin A deficiency during pregnancy inhibits Ca

2+

influx of hippocampal neurons in newborn rats by decreasing the expression of NMDA receptor 1 in the hippocampus

which may be one of the mechanisms underlying cell damage.