Journal of Applied Physiology, Vol 57, Issue 5 1597-1601, Copyright © 1984 by American Physiological Society
Modification of lymph by sheep caudal mediastinal node: effect of intranodal endotoxin
T. H. Adair, J. P. Montani and A. C. Guyton
Postnodal lymph from the sheep caudal mediastinal node (CMN) is used by
many investigators to assess lung vascular protein permeability. We
explored the possibility that damage to the CMN blood-lymph barrier could
produce increases in postnodal lymph flow and lymph-to-plasma protein
concentration ratio (L/P) characteristic of lung vascular damage.
Escherichia coli endotoxin (0.049 micrograms/min) was infused into a
prenodal lymph vessel to the CMN in the conscious sheep, and postnodal
lymph was collected for the next 7 h. Intranodal endotoxin caused an 80%
increase in postnodal lymph flow and a 30% increase in postnodal L/P.
Because there was no indication that the endotoxin had exerted a systemic
effect, the lymph response to endotoxin was attributed to a direct effect
of endotoxin on the blood-lymph barrier of the CMN. We conclude that
significant increases in postnodal lymph flow and L/P characteristic of
lung vascular damage can occur when the blood-lymph barrier of the CMN
becomes damaged.
