DEVELOPMENT OF A NEW EXPERIMENTAL APPARATUS FOR STUDYING OF MECHANICAL ACTIVITY OF ISOLATED ARTERIOLES.

[1]一种新的测定离体小动脉机械活动实验装置的研制--标本的制备和解剖例如，脑、脊髓或鸡的囊袋，并置于装有含有1%BSA的MOPS缓冲生理盐溶液的冷却解剖室中。将分离的小动脉小心地从解剖室转移到安装在倒置显微镜载物台上的温控插管室中。插管通过使用安装在显微操作器上的同心玻璃吸管系统在两端插管分离的小动脉，显微操作器安装在插入的显微镜载物台上。通过对保持移液管的内腔施加真空，将小动脉的一端轻轻拉入移液管中。将灌注移液管插入L ...更多信息 微动脉的内腔。然后用同样的方法在小动脉的另一端插管。仪器插管后，将两个微量移液器连接到水压计上，用于通过独立的储液器调节管腔内压力。另一个由压力计加压的储液器通过三通液体开关插入到小动脉和上游储液器之间的液体通道中，用摄像机记录插管小动脉的图像，并在电视监视器上显示。使用结合MacLab Chart数据采集系统的视频卡尺手动测量小动脉管腔直径。[2]生理应用我们研究了离体兔脊髓小动脉对血流的反应，特别是内源性一氧化氮（NO）和前列腺素（PGs）。将小动脉（直径约100 μ m）在两端用微玻璃移液管插管，并在恒定压力（约60 mmHg）下灌注。小动脉在37 ° C下以其最大扩张的-26%产生自发张力。用吲哚美辛（10 μ m）治疗产生了显着的小动脉直径减少，而用一氧化氮产生抑制剂（L-NAME）治疗没有产生显着的变化。然而，在10 μ M吲哚美辛的存在下，30 μ M L-NAME引起小动脉直径的显著减小，这在另外给予1 mM L-精氨酸时完全逆转。提示内皮细胞释放的NO和PGs在兔脊髓小动脉血流介导的血管舒张中起重要作用。少

[1] DEVELOPMENT OF A NEW EXPERIMENTAL APPARATUS FOR STUDYING OF MECHANICAL ACTIVITY OF ISOLATED ARTERIOLESPreparation and dissectionExperimental materials, i. e., brain, spinal cord, or chick pouch, were rapidly removed and placed in a cooled dissection chamber filled with MOPS-buffered physiological salt solution containing 1% BSA.The chamber is placed on a recessed Plexiglas well, and chilled fluid is circulated through the well jacket from a cooling thermopump. The isolated arteriole was carefully transferred from the dissection chamber to a temperature-controlled cannulation chamber mounted on a stage of an inverted microscope.CannulationThe isolated arteriole was cannulated at both ends by using a system of concentric glass pipettes mounted on a micromanipulator which was equipped on the stage of the inserted microscope. By applying vacuum to the lumen of the holding pipette, one end of the arteriole was gently pulled into the pipette. The perfusion pipette was inserted into the l … More umen of the arteriole. Then the other end of the arteriole was cannulated in the same manner.InstrumentationAfter the cannulation, both micropipettes were connected to water manometers used to adjust intraluminal pressure via independent reservoirs. Another fluid reservoir pressurized by the manometer could be inserted into the fluid path between the arteriole and the upstream reservoir by menas of a three-way liquid switch.The image of the cannulated arteriole was recorded using a video camera and displayd on a television monitor. Arteriolar luminal diameters were measured manually using a video caliper incorporated with MacLab Chart data acquisition system.[2] PHYSIOLOGICAL APPLICATIONWe investigated the responses of isolated rabbit spinal arterioles to flow with special reference to endogenous nitric oxide (NO) and prostaglandins (PGs). The arterioles (-100mum in diameter) were cannulated at both ends with microglass pipettes, and perfused at constant pressure (-60mmHg). The arterioles developed spontaneous tone at 37ﾟC by -26% of their maximum dilation. Treatment with indomethacin (10mum) produced a significant decrease in the arteriolar diameter, whereas treatment with a nitric oxide production inhibitor (L-NAME) produced no significant change. In the presence of 10muM indomethacin, however, 30muM L-NAME caused a marked decrease in the arteriolar diameter, which was completely reversed with additional administration of 1mM L-arginine. These findings suggest that both NO and vasodilative PGs released from the endothelial cells may play important roles in the flow-mediated vasodilation in the rabbit spinal arterioles. Less