Lymph flow during fluid absorption from rat jejunum.

The relation between intestinal lymph flow (JL) and fluid absorption rate (JV) was studied with an in vivo jejunal preparation of the rats under pentobarbital sodium anesthesia. It was found that in more than 60% of the rats there is a communication between hepatic and intestinal lymphatics. JL was significantly higher in these rats whether the intestine was in the nonabsorptive state or during fluid absorption. This is undoubtedly due to the contribution of hepatic lymph. The increased lymph flow due to fluid absorption in the rats without hepatic lymphatic communication varied over a wide range of 0-27% of the absorbed volume with a mean value of 8%. In the rats with simultaneous fat absorption, JV did not change but JL decreased to about 3% of the absorbed volume. There was no correlation between JL and JV. Furthermore, obstruction of JL caused no change in JV, indicating that the lymphatic system is not indispensable in fluid transport. From these findings, it is concluded that JL is not a constant proportion of the absorbed volume but depends on the pathophysiological state of the intestine.