Endothelial modulation of pH-dependent pressor response in isolated perfused rabbit lungs

Kazuhiro Yamaguchi, Tomoaki Takasugi, Hirohumi Fujita, Masaaki Mori, Yoshitaka Oyamada, Kohichi Suzuki, Atsushi Miyata, Takuya Aoki, Yukio Suzuki

研究成果: Article

34 引用 (Scopus)

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With the use of isolated perfused rabbit lungs (n = 152), roles of endothelium-derived relaxing factor (EDRF) in pulmonary vascular responses to hypocapnia and hypercapnia were studied. Lungs were ventilated with a gas mixture containing 1, 5, or 10% CO2 and 21% O2, adjusting the perfusate pH to 7.8, 7.4, or 7.1, respectively. Methemoglobin (MetHb), hemoglobin (Hb), methylene blue (MB), and L-argininosuccinic acid (L-ASA) were used as modulators of EDRF. To eliminate augmented shear stress, we used papaverine during hypercapnia. As a measure of EDRF, we spectrophotometrically examined nitric oxide (NO) metabolites in the perfusate. Hypocapnia and hypercapnia evoked, respectively, unsustainable vasodilatation and vasoconstriction. Hb, MB, and L-ASA, but not MetHb, produced an increase in baseline pulmonary arterial pressure (P(pa)). These agents also exacerbated vasoconstriction during hypercapnia. Hypercapnia and hypocapnia caused an increase and decrease, respectively, in EDRF production. L-ASA suppressed EDRF production in hypercapnic lungs. Papaverine did not suppress EDRF production under hypercapnia. In conclusion, 1) the effects of pH on pulmonary circulation are transient, 2) the increase in P(pa), caused by hypercapnia is modulated by EDRF, and 3) the pulmonary EDRF genesis is activated by hypercapnic acidosis but suppressed by hypocapnic alkalosis.

元の言語English
ページ(範囲)H252-H258
ジャーナルAmerican Journal of Physiology - Heart and Circulatory Physiology
270
発行部数1 39-1
出版物ステータスPublished - 1996 2 26

    フィンガープリント

ASJC Scopus subject areas

  • Physiology
  • Cardiology and Cardiovascular Medicine
  • Physiology (medical)

これを引用

Yamaguchi, K., Takasugi, T., Fujita, H., Mori, M., Oyamada, Y., Suzuki, K., Miyata, A., Aoki, T., & Suzuki, Y. (1996). Endothelial modulation of pH-dependent pressor response in isolated perfused rabbit lungs. American Journal of Physiology - Heart and Circulatory Physiology, 270(1 39-1), H252-H258.