Vovenko E P, Sokolova I B, Loshchagin O V
I. P. Pavlov Institute of Physiology, Russian Acad. Sci., St. Petersburg, 199034, Nab. Makarova, 6.
Ross Fiziol Zh Im I M Sechenova. 2002 Mar;88(3):372-80.
Using oxygen microelectrodes, distribution of oxygen tension (pO2) has been studied in venules of the rat brain cortex at normobaric hyperoxia (spontaneous breathing with pure oxygen). It has been shown that inhalation of oxygen results in sharp increase of pO2 in majority of the venules under study. The pO2 distribution along the length of venous microvessels of 7-280 microns in diameter is best approximated by equation: pO2 = 76.44 e-0.0008D, n = 407. The pO2 distribution was characterised by extremely high pO2 values (180-240 mm Hg) in some minute venules. Heterogeneity of pO2 distribution in venous microvessels at hyperoxia was shown to be significantly increased. Profiles of pO2 between neighbouring arterioles and venules were for the first time measured. The data clearly evidenced that O2 diffusional shunting took place between cortical arterioles and venules, provided they were distanced from each other for not over 80-100 microns. Distribution of pO2 in venules has been shown to be dependent on the blood flow in the brain cortical microvessels.
利用氧微电极，研究了常压高氧（纯氧自主呼吸）条件下大鼠大脑皮质小静脉中的氧分压（pO₂）分布。结果表明，吸入氧气会导致大多数被研究小静脉中的pO₂急剧升高。直径为7 - 280微米的静脉微血管沿线的pO₂分布最符合以下方程：pO₂ = 76.44 e⁻⁰.⁰⁰⁰⁸D，n = 407。在一些微小静脉中，pO₂分布的特点是具有极高的pO₂值（180 - 240毫米汞柱）。高氧条件下静脉微血管中pO₂分布的异质性显著增加。首次测量了相邻小动脉和小静脉之间的pO₂剖面图。数据清楚地证明，皮质小动脉和小静脉之间发生了氧气扩散分流，前提是它们之间的距离不超过80 - 100微米。小静脉中pO₂的分布已被证明取决于大脑皮质微血管中的血流。
