AJP - Heart and Circulatory Physiology, Vol 258, Issue 4 1126-H1131, Copyright © 1990 by American Physiological Society
Hemodynamic changes associated with anaphylaxis in parasite-sensitized rats
R. Mathison, A. D. Befus and J. S. Davison
Department of Medical Physiology, University of Calgary, Alberta, Canada.
Thirty days after infection with the parasite Nippostrongylus brasiliensis,
microcirculatory changes associated with worm allergen-induced anaphylactic
shock in pentobarbital-anesthetized rats were studied. Allergen challenge
decreased heart rate, mean arterial blood pressure, and cardiac output (CO)
for 60 min, although CO increased markedly by 240 min. Blood flow
(ml.min-1.g wet tissue-1) was reduced to most tissues, with the exception
of the kidneys, hepatic arterial, heart, and brain, for 60 min. Depressed
flow to the adrenals and enhanced flow to the kidneys, trachea, stomach,
and mesentery were observed at 240 min. The percent distribution of cardiac
output per gram wet tissue (%CO/g) increased initially to the kidneys,
heart, liver, and cervical spinal cord, decreased to the spleen and cecum,
and remained unchanged to other gastrointestinal tissues. The %CO/g to most
tissues returned to normal by 60 min but decreased to the adrenals at 240
min. The intestine is an important organ affected by anaphylaxis in the
rat, and the liver may participate in alleviating anaphylaxis.
