Vitamin D deficiency impairs spatial learning in adult rats.

BACKGROUND Through its membrane and intracellular receptors, vitamin D regulates many vital functions in the body including its well known actions on musculoskeletal system. Growing body of evidences demonstrate that vitamin D undergoes some of behavioral aspects of neurocognition. The present study was designed to evaluate the effect of food regimens without vitamin D or with a supplement of 1,25(OH)2D3 on spatial performance of adult rats. METHODS The animals were trained in the Morris water maze to find a hidden platform. The time spent and the distance traveled to find the platform, speed of navigation and the percentage of unsuccessful trials were considered for assessment of the task learning. RESULTS Our findings indicated that the vitamin D-deprived rats had a significant lower performance compared to both the controls and the animals receiving 1,25(OH)2D3 supplementation. Concerning the unsuccessful trials, lack of vitamin D resulted in the highest failures in the maze navigation. The regimen with additional 1,25(OH)2D3 did not considerably influence learning of the maze task. CONCLUSION We concluded that while vitamin D deficiency deteriorates the spatial task learning, the 1,25(OH)2D3 supplementation did not effectively underlie the maze performance.