Nowicki P T, Hansen N B, Menke J A
Am J Physiol. 1987 Feb;252(2 Pt 1):G190-4. doi: 10.1152/ajpgi.1987.252.2.G190.
The effect of reduced perfusion pressure on neonatal intestinal blood flow, vascular resistance, arterio-venous oxygen content (a-v O2), and oxygen uptake was studied in nine fasted newborn piglets, aged 5-6 days. Successive reductions of intestinal perfusion pressure were achieved by a clamp on the thoracic aorta. Intestinal blood flow decreased after each reduction of perfusion pressure. Intestinal vascular resistance increased and Gf, a measure of flow control, was negative after all but the final, most severe reduction of perfusion pressure. However, intestinal a-v O2 increased after each pressure reduction and intestinal oxygen uptake was thus maintained at greater than or equal to 95% of its baseline value until perfusion pressure was reduced to less than or equal to 70% of its base-line value. The neonatal intestine maintains tissue oxygen uptake during moderate hypotension, and this is accomplished by regulation of a-v O2, rather than by regulation of blood flow.
在9只5 - 6日龄的禁食新生仔猪中，研究了灌注压降低对新生仔猪肠道血流、血管阻力、动静脉氧含量（a-v O2）和氧摄取的影响。通过钳夹胸主动脉实现肠道灌注压的连续降低。每次灌注压降低后，肠道血流均减少。除最后一次最严重的灌注压降低外，其余每次降低后肠道血管阻力均增加，且作为流量控制指标的Gf为负值。然而，每次压力降低后肠道a-v O2均增加，因此在灌注压降至其基线值的70%及以下之前，肠道氧摄取维持在其基线值的95%及以上。新生仔猪肠道在中度低血压期间维持组织氧摄取，这是通过调节a-v O2而非调节血流来实现的。
