Effects of growth hormone and triiodothyronine administration of the localization of ¹⁴C-D-glucose on regenerating sciatic nerve in rabbits

Abstract

In the present study the effect of the administration of GH and T₃ on glucose distribution in the regenerating nerve was studied. The right sciatic nerve of 40 male rabbits was crushed at a specific site so that axonotmesis ensued. The animals were divided into two equal groups: one for the study of the effects of human growth hormone (hGH) and the other of triiodothyronine (T₃). In all animals ¹⁴C-D-glucose ([¹⁴C]D-G) was injected iv as a tracer. The sciatic nerves from both sides were removed from all animals, divided into four equal segments and checked for radioactivity. In all cases an increased concentration of [¹⁴C] D-G appeared in the crushed nerve as compared with the intact one. GH administration caused a decrease in [¹⁴C] D-G uptake in both intact and injured nerves. T₃ administration caused a significant decrease in [¹⁴C]D-G levels fn the blood but did not substantially change [¹⁴C]D-G uptake in the crushed nerves as a whole. T₃ administration appeared also to cause a peripheral displacement of the site of maximum [¹⁴C] D-G concentration in the injured nerve, indicating possibly an increased regeneration rate.