AJP - Heart and Circulatory Physiology, Vol 237, Issue 4 504-H513, Copyright © 1979 by American Physiological Society
Experimental studies of the fibrinogen response to hemorrhage
E. B. Reeve, A. Stephens and T. H. Carlson
Rabbits were bled 20 ml/kg body wt over approximately 1 h, and the changes
in hematocrit, plasma total protein, and fibrinogen concentrations, red
cell and plasma volumes, and masses of total protein and fibrinogen in the
plasma during and for 4 days after the hemorrhage were monitored. Ten
percent of plasma fibrinogen was transferred from the interstitial fluids
during the hemorrhage, and total plasma fibrinogen was raised to 140% of
initial levels by 1 day later. 131I-labeled fibrinogen was given
intravenously 1 day before a 20 ml/kg hemorrhage, and simulation methods
described in the APPENDIX were used to define changes in the posthemorrhage
fractional rates: transcapillary transfer rate (j1), lymphatic return rate
(j2), and catabolic rate of fibrinogen (j3): j1 was unchanged but j2
increased and j3 briefly declined. In the day after hemorrhage fibrinogen
synthetic rate increased approximately threefold to restore plasma
fibrinogen concentrations to initial levels, but then returned to normal or
subnormal levels. The alterations in j2 and j3 save about 20% of the
synthetic work that would otherwise be required to restore plasma
fibrinogen levels to normal.
