Metabolic studies with zinc-65. IX. Zinc in the hair of guinea pigs

Abstract

Metabolic studies with Zn-65. IX. Zn in hair of the guinea pig

The dinamics of zinc-65 intake and elimination by hair and skin have been stydied in the guinea pig.

The concentration of zinc in the hair increase from it administration via intraperitoneal until the 24th day in which the máximum valué is reached, 0.48 % of injected zinc-65 per grame of hair, following two exponential functions. From the inyection until the 6th day respond to: Y1 = 0.03e0.3425t

From the 6th to the 24th in accord with: Y2 = 0.14e0.0659t

After the 24th day and until the 70 the zinc concentration decrease following the function: Y3 = 1.1e-0.0298t

The zinc concentration in the skin has a máximum for the 15th day, 0.22 % of injected zinc-65 per grame of skin. From that day decreases following the function: Y = 0.59e-0.0651t

This shows a biological half life of 10.5 days.

Pernales have higher hair zinc concen­tration than males, but its curves of variation are parallel. The equation repre­ sentativo of the decrease period shows a biological half life of 142 days.

The percentage of the zinc-65 total body burden which is content in the hair and skin together increase in the first 30 days depending on the function: Y1 = 12.8e0.0254t

From this day and to the end of our experiments it is followed the equation: Y2 = 30.5e0.0008t

Data are indicator of the zinc retention and elimination character of the hair-skin system.