THE ABSORPTION OF BICARBONATE-SALINE SOLUTIONS BY THE SMALL INTESTINE AND COLON OF THE WHITE RAT

¹ The Department of Biochemistry, University of Oxford

1. During the absorption of isotonic solutions containing 160 mM Na, 135 mM Cl and 25 mM HCO₃, the contents of rat jejunum become progressively more acid than the contents of the ileum or colon.

2. During absorption there is a net entry of total CO2 into the contents of the ileum and colon, while from the jejunum there is a net absorption of total CO_2.

3. The carbonic anhydrase inhibitor 6063 depresses the absorption of water and electrolytes from the jejunum, ileum and colon, and reverses the direction of net movement of CO₂ in ileal segments.

4. After absorption of saline solutions, the water content of the wall of the jejunum and colon is increased.

Note:

I am grateful to Miss E. C. Wills for skilled assistance, and to Mr. J. T. Cox for constructing the flame photometer. 6063 ("Diamox’) was kindly supplied by Cyanamid Products Ltd., London.