New water absorption and mucosal morphometry of ileal reservoirs and of ileal segments transposed to the colon in the cat.

New water absorption and changes in villous height were studied in ileal reservoirs and in ileal segments transposed to the colon in the cat. A continuous perfusion technique was used to estimate net water absorption. The villous height was reduced both in ileal reservoirs and in the transposed segments compared with normal ileum. The serosal area of the reservoir was significantly increased compared with the initial segment used in construction of the reservoir. The reservoir showed a reduced net water absorption rate per unit serosal area compared with a control segment, but when the absorption of the whole reservoir was compared with that of a control segment of the same initial length, there was no significant change. In the transposed segments no significant change in net water absorption could be revealed. Data from both series of experiments showed a positive correlation between net water absorption per unit serosal area and villous height. Blood flow registration in ileal segments transposed to the colon showed a blood flow of the same magnitude in the transposed segment as in the control segment.