Nucleic acid and protein content of rat cecum mucosa in dietary adaptation-growth by cellular hyperplasia.

The deoxyribonucleic acid (DNA), ribonucleic acid (RNA) and protein content of the isolated cecum mucosa was determined in control rats and rats with adaptive cecum growth induced by dietary polyethylene glycol. Feeding the polymer resulted in an increase in the total amount of mucosal nucleic acids and protein which was statistically significant after 2-4 days and reached twice the control value after 2 months. During growth, the protein/DNA, protein/RNA and RNA/DNA ratios remained unaltered, indicating hyperplasia and not hypertrophy of the epithelial cells. The water content of the mucosa increased from 75 to 81% during adaptation, possibly related to the stimulation in active sodium transport reported earlier. Recalculation of parallel Na-K-ATPase data on the basis of DNA demonstrated a doubling of Na-K-ATPase activity per mg DNA in the fully adapted cell.