The effects of high dose vitamin D on the sympathetic skin response in rats

Vitamin D is a fat-soluble hormone formed predominantly in the skin when exposed to UVB from the sun or absorbed from restricted dietary sources. Vitamin D is a significant regulator of calcium and phosphorus homeostasis and controls many other biological processes, including the immune system, cell growth and division. Electrodermal activity (EDA) measures the skin conductance level (SCL) which innervating of sweat glands. Increased SCL indicate increase sympathetic activity and increase sweat secretion. There is no previous study linked to the effect of vitamin D on electrodermal activity. And the purpose of the present study is to investigate the effect of Vitamin D on sympathetic nerve activity at different high doses using electrodermal activity. This study was carried out with 36 rats. This study was carried out with 36 rats. The rats were divided into 3 groups as sham group receiving tap water by oral gavage, medium dose vitamin group (400IU) and high dose vitamin group (1000IU). A significant difference was found between the medium dose group and the sham group for tonic SCL (p value =0.027). A significant difference was also found for phasic SCL between the medium dose group and the sham group (p value = 0.001) and between the high dose group and the sham group (p value = 0.013). There was no difference when each group's tonic and phasic SCL were compared separately. Our findings showed that sympathetic skin response was increased with vitamin D supplementation, and there was no significant difference between high and medium dose vitamin D. In conclusion, sweat gland activity and stress response increased with the increase in vitamin D administration, but no dose-dependent effect was observed. Keywords: Vitamin D, Sympathetic skin response, Skin conductance level, Rat