Strong gastric contractions cause mucosal ischemia.
Strong gastric contractions cause mucosal ischemia.
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强烈的胃收缩导致粘膜缺血。
DOI：
10.1152/ajpgi.1991.260.3.g524
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发表时间：
1991
期刊：
影响因子：
--
通讯作者：
Guth,PH
中科院分区：
文献类型：
--
作者：
Livingston,EH;Howard,TJ;Garrick,TR;PassaroJr,EP;Guth,PH
肠段的收缩导致其血流的改变。然而，收缩和粘膜血流之间精确的时间和空间关系是未知的。大鼠配备应变计力传感器，并植入银丝电极到胃的肌层外。在电场刺激收缩过程中，对胃粘膜的运动性和血流进行了体内显微镜观察。收缩起源于中间体，宽度为0.237 +/- 0.018 cm，以0.133 +/- 0.024 cm/s的速度沿着体行进，持续时间为5.9 +/- 0.1 s。胃窦收缩宽度为0.174 ± 0.032 cm，行进速度为0.070 ± 0.009 cm/s，持续时间为5.6 ± 0.7 s。在收缩期间，在收缩的峰值处，体中的毛细血管流速从410 +/-105微米/秒的基础值降低到206 +/-104微米/秒。在收缩释放后5秒，观察到充血，流速增加至570 +/-102微米/秒。在胃窦中，无论初始流速如何，在收缩期间血流完全停止，并且在收缩解除时未发生充血;相反，流速缓慢恢复至基线值。在这两个区域中，流量减少与力传感器测量的收缩同相。这些研究提供了直接的证据，有力的胃收缩可以有效地减少或停止胃粘膜血流。
Contractions of a segment of bowel result in alterations of its blood flow. However, the precise temporal and spacial relationships between contractions and mucosal blood flow are unknown. Rats were fitted with strain gauge force transducers and implanted with silver wire electrodes into the muscularis externa of the stomach. In vivo microscopic observation of motility and of the gastric mucosal blood flow was performed during electrical field-stimulated contractions. Contractions originated in the midcorpus, were 0.237 +/- 0.018 cm wide, traveled along the corpus at 0.133 +/- 0.024 cm/s, and had a duration of 5.9 +/- 0.1 s. Antral contractions were 0.174 +/- 0.032 cm wide, traveled at 0.070 +/- 0.009 cm/s, and had a duration of 5.6 +/- 0.7 s. During the contraction, capillary flow velocity in the corpus decreased from a basal value of 410 +/- 105 to 206 +/- 104 microns/s at the peak of a contraction. Five seconds after the contraction was released hyperemia was observed with the flow velocity increasing to 570 +/- 102 microns/s. In the antrum, flow stopped completely during the contraction irrespective of the initial flow velocity and no hyperemia occurred with release of the contraction; rather, flow velocity slowly returned to baseline values. In both regions the flow reductions were in phase with the contractions as measured by the force transducers. These studies provide direct evidence that strong gastric contractions can effectively reduce or stop gastric mucosal blood flow.