Hepatic lymph flow and protein concentration during intravenous saline infusion and intestinal fluid absorption

Abstract

A simple procedure for the collection of the postnodal and prenodal hepatic lymph in the rats under pentobarbital anesthesia is described. Lymph flow ( J L) from the main hepatic lymph duct (postnodal), protein concentration in both the lymph ( C L) and plasma ( C P), and the C L C P ratio were 0.22 ± 0.1 ml/kg of body weight · hr (0.66 ± 0.3 ml/100 g wet liver wt · hr), 4.3 ± 0.5 and 6.2 ± 0.3 g%, and 0.69 ± 0.1 (mean ± SE), respectively. There was no significant difference in C L between prenodal and postnodal lymph in the fasted or unfasted rats. During intestinal fluid absorption with an increase in intestinal J L, postnodal hepatic J L or C L did not change. During intravenous saline infusion with lowering of plasma oncotic pressure, there was a small increase in prenodal J L (by ∼160%) with some decrease (by 16%) in C L C P ratio but a much larger increase in postnodal J L (by ∼700%) with a significant decrease (by 55%) in C L C P ratio. The results demonstrate that both flow and protein concentration of the postnodal lymph differ greatly from that of the prenodal lymph due to modification during transit through the lymph node. The small increase of the prenodal J L with negligible change in C L C P ratio during saline infusion suggests that oncotic pressure grandient plays a minor or insignificant role in the transsinusoidal fluid transport in the liver.