Calcitonin-mediated changes in plasma tryptophan and brain 5-hydroxytryptamine and acetylcholinesterase activity in rats

Abstract

After a single injection of calcitonin (20 M.R.C. units/kg body wt.) marked decreases in both Ca2+ and free tryptophan in plasma were observed, during the initial period of the treatment (up to 1 h). However, 5-hydrotryptamine contents of the whole brain and the cerebral acetylcholinesterase activity were greatly enhanced. The cerebellar acetylcholinesterase activity was not influenced by calcitonin.