Analysis of hippocampal RNA in rats with genetically determined differences in learning ability.

Abstract

1. Breeding for speed of formation of a food-getting motor conditioned reflex in the course of 12 generations led to an increase in the intensity of synthesis of nuclear and cytoplasmic fractions of hippocampal RNA in quick-learning animals compared with slow-learning. 2. Electrophoretic analysis of nuclear and cytoplasmic fractions of hippocampal RNA revealed the presence of a similar series of classes of RNA in the initial and trained groups of specially bred animals. 3. In the region of high-molecular-weight classes of nRNA incorporation of radioactive precursor was at a higher level in quick-learning animals than in slow-learning. 4. In connection with training an increase was observed in the incorporation of radio-active precursors in the region of high-molecular-weight classes of nRNA and in the 18S-4S RNA region of cRNA. 5. Incorporation of3H-uridine into polyA-RNA and changes in incorporation of label connected with training were significantly greater in quick-learning animals.