AJP - Gastrointestinal and Liver Physiology, Vol 251, Issue 5 718-G723, Copyright © 1986 by American Physiological Society
Age-related superior mesenteric arterial flow changes in piglets: effects of feeding and hemorrhage
A. C. Yao, P. M. Gootman, P. P. Frankfurt and S. M. DiRusso
Cardiovascular (CV) responses to feeding before and after 15% blood volume
hemorrhage (H) were studied in lightly anesthetized piglets less than or
equal to 2-days and greater than 2-wk-old. Superior mesenteric (Mes) and
renal (Ren) arterial flows (F) were registered by electromagnetic probes
before and continuously for 2 h after milk feeding (26 ml/kg) by gavage.
Postprandially, in piglets less than or equal to 2-days-old MesF tended to
increase (maximum change, mean +/- SE, 16.0 +/- 4.7%) at 30 min, whereas
Mes vascular resistance (R) significantly decreased at 30, 90, and 120 min
(17.3 +/- 6.2%). In piglets greater than 2-wk-old, MesF significantly
increased by 30 min, which lasted 120 min (37.7 +/- 11.7%); MesR decreased
by 20.0 +/- 5.8% at 90-120 min. Compared with the less than or equal to 2
days olds, the older piglets demonstrated greater and more sustained
postprandial MesF increase. After H, regional F and pulse pressure (PP)
decreased, heart rate and R increased in both groups. After stabilization,
feeding induced insignificant CV changes in less than or equal to 2-day-old
piglets. In contrast, increased MesF (44 +/- 14.4%) and PP (24 +/- 8.5%)
and decreased MesR (31 +/- 8.9%) were observed in the greater than
2-wk-olds. MesF changes differed significantly between the age groups. The
Ren vascular bed showed no consistent response in both age groups. Thus Mes
vascular responses to feeding with or without preceding H in developing
piglets were age related.
