Kiel J W, Riedel G L, Shepherd A P
Gastroenterology. 1987 Jul;93(1):12-20. doi: 10.1016/0016-5085(87)90307-6.
Although autoregulation of total blood flow has been demonstrated in the stomach, autoregulation of gastric mucosal blood flow has not been investigated due to the limitations of previously available mucosal blood flow measuring techniques. We recently evaluated laser-Doppler velocimetry for use in the stomach and found it to yield continuous, superficial measurements of either mucosal or muscularis blood flow. In the present study, simultaneous measurements of total, mucosal, and muscularis blood flows and arteriovenous oxygen difference were made during step decreases in perfusion pressure in chambered segments of resting canine stomach. As perfusion pressure was decreased from 180 to 35 mmHg, oxygen consumption remained relatively constant at 1.5 ml/min X 100 g and only became blood flow-dependent when perfusion pressure was set below 90 mmHg and total blood flow fell below 35 ml/min X 100 g. Oxygen consumption was maintained partly by increased oxygen extraction; however, there was also a progressive increase in the tendency for total blood flow autoregulation after each drop in perfusion pressure. Mucosal blood flow was also well autoregulated over the physiologic range of perfusion pressure and remained relatively constant during the plateau portion of the oxygen consumption curve. Our results indicate that in the resting stomach, oxygen consumption is maintained by changes in oxygen extraction in conjunction with autoregulation of mucosal and total blood flow.
尽管已经证实胃的总血流量存在自身调节，但由于先前可用的粘膜血流量测量技术的局限性，胃粘膜血流量的自身调节尚未得到研究。我们最近评估了激光多普勒测速仪在胃中的应用，发现它能对粘膜或肌层血流量进行连续的浅表测量。在本研究中，在静息犬胃的分隔段灌注压力逐步降低期间，同时测量了总血流量、粘膜血流量、肌层血流量和动静脉氧差。当灌注压力从180 mmHg降至35 mmHg时，氧耗量保持相对恒定，为1.5 ml/min×100 g，只有当灌注压力设定在90 mmHg以下且总血流量降至35 ml/min×100 g以下时，氧耗量才开始依赖血流量。氧耗量部分通过增加氧摄取来维持；然而，每次灌注压力下降后，总血流量自身调节的趋势也在逐渐增加。在灌注压力的生理范围内，粘膜血流量也能很好地进行自身调节，并且在氧耗量曲线的平台期保持相对恒定。我们的结果表明，在静息胃中，氧耗量通过氧摄取的变化以及粘膜和总血流量的自身调节来维持。
