Studies of RNA metabolism in the nerve cells of hippocampus during training in rats.

Direct evidence is presented that training to change behavior initiates synthesis of specific species of mRNA in pyramidal nerve cells of CA3 of the hippocampus in rats. Reversal of handedness was used as goal-directed operant test and active controls. Newly synthesized poly(A) associated mRNA with S value of 25 and a stimulation of poly(A) lacking mRNA of 8--9 S and 16--17 S were found in the CA3 nerve cells of trained but not in active controls.