Yao A C, Gootman P M, Frankfurt P P, DiRusso S M
Am J Physiol. 1986 Nov;251(5 Pt 1):G718-23. doi: 10.1152/ajpgi.1986.251.5.G718.
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.
在小于或等于2日龄和大于2周龄的轻度麻醉仔猪中，研究了15%血容量出血（H）前后喂食对心血管（CV）的反应。通过电磁探头在通过灌胃给予牛奶喂食（26 ml/kg）之前以及之后连续2小时记录肠系膜上动脉（Mes）和肾动脉（Ren）血流（F）。餐后，在小于或等于2日龄的仔猪中，肠系膜上动脉血流（MesF）在30分钟时趋于增加（最大变化，平均值±标准误，16.0±4.7%），而肠系膜上血管阻力（R）在30、90和120分钟时显著降低（17.3±6.2%）。在大于2周龄的仔猪中，肠系膜上动脉血流（MesF）在30分钟时显著增加，并持续120分钟（37.7±11.7%）；肠系膜上血管阻力（MesR）在90至120分钟时降低了20.0±5.8%。与小于或等于2日龄的仔猪相比，年龄较大的仔猪餐后肠系膜上动脉血流增加更大且更持久。出血后，两组的局部血流（F）和脉压（PP）均降低，心率和血管阻力（R）均升高。稳定后，小于或等于2日龄的仔猪喂食引起的心血管变化不显著。相比之下，在大于2周龄的仔猪中观察到肠系膜上动脉血流增加（44±14.4%）和脉压增加（24±8.5%）以及肠系膜上血管阻力降低（31±8.9%）。不同年龄组之间肠系膜上动脉血流变化存在显著差异。在两个年龄组中，肾血管床均未表现出一致的反应。因此，发育中的仔猪在有或无先前出血情况下喂食时肠系膜血管反应与年龄相关。
