THE EFFECTS OF INTRAVENOUS INFUSION OF SOLUTIONS WITH DIFFERENT COLLOID OSMOTIC PRESSURES ON RAT MESENTERIC LYMPH PRESSURE
Abstract
The effects of intravenous infusion of solutions
of varied colloid osmotic pressure on
mesenteric lymph pressure were measured by a
glass micropipette. The lymph pressure was 4.0
± 1.6 cm H20 between the second and third
valve of rat mesenteric lymphatic vessels with
diameter of 101 ± 25μm (mean ± SD). Intravenous
infusion of 1 ml/100g body weight
(B.W.) of isotonic saline, 5% glucose solution,
and 20% glucose solution increased the lymph
pressure by 1.6 ± 0.5 cm H20, 1.5 ± 0.3 cm
H20 and 2.0 ± 1.0 cm H20, respectively. Infusion
of 2 ml/100g B.W. of the same solutions
increased the lymph pressure by 3.3 ± 1.3 cm
H20, 3.3 ± 1.6 cm H20 and 3.7 ± 0.8 cm
H20, respectively . Infusion of hydroxyethyl
starch solution, with colloid osmotic pressure of
25 mmHg, minimally altered the lymph
pressure. One ml/100g B.W. infusion of low
molecular weight dextran solution, with colloid
osmotic pressure of 162 mmHg, decreased the
lymph pressure by 1.3 ± 0.9 cm H20, and 2
ml/1OOg B.W . infusion of this solution decreased
the lymph pressure by 2.0 ± 1.0 cm H20. The
different effects on lymph pressure derive from
the differences in colloid osmotic pressure of these
solutions in conformity with the Starling
hypothesis.