Martinez-Lemus L A, Hester R K, Becker E J, Jeffrey J S, Odom T W
Department of Poultry Science, Texas Agricultural Experiment Station and Colleges of Medicine and Veterinary Medicine, Texas A&M University, College Station, Texas 77843, USA.
Am J Physiol. 1999 Jul;277(1):R190-7. doi: 10.1152/ajpregu.1999.277.1.R190.
Among chicken strains, broilers are prone to pulmonary hypertension, whereas Leghorns are not. Relaxations to endothelium-dependent (ACh, A23187) and endothelium-independent [sodium nitroprusside (SNP), papaverine (PPV)] vasodilators were compared in preconstricted pulmonary artery (PA) rings from these chicken strains. ACh (10(-7), 10(-6), and 10(-5) M)- and A23187 (10(-6) and 10(-5.5) M)-induced relaxations were smaller (P < 0.05) in broilers than Leghorns. N(G)-nitro-L-arginine methyl ester (10(-3.5) M) caused similar reductions in ACh-induced relaxations in both strains. L-Arginine (10(-4) M) enhanced ACh-induced relaxations more in broilers than Leghorns. Relaxations to 10(-10)-10(-6) M SNP did not differ between strains, but were greater (P < 0.05) in broilers than Leghorns at higher concentrations (10(-5) and 10(-4) M). PPV (10(-4) M)- and SNP (10(-4) M)-induced maximal relaxations were greater in broilers than in Leghorns (176.2 +/- 14.7 vs. 120.9 +/- 14.7% and 201.3 +/- 7.8 vs. 171.2 +/- 10.7%, respectively, P < 0.05). Broiler PA rings appear to have increased intrinsic tone and reduced endothelium-derived nitric oxide activity, both of which may contribute to the susceptibility of broiler chickens to pulmonary hypertension.
在鸡的品种中，肉鸡易患肺动脉高压，而来航鸡则不易患病。比较了这些鸡品种的预收缩肺动脉（PA）环对内皮依赖性（乙酰胆碱、A23187）和非内皮依赖性[硝普钠（SNP）、罂粟碱（PPV）]血管舒张剂的舒张反应。乙酰胆碱（10⁻⁷、10⁻⁶和10⁻⁵ M）和A23187（10⁻⁶和10⁻⁵.⁵ M）诱导的舒张反应在肉鸡中比来航鸡小（P < 0.05）。N⁻硝基⁻L⁻精氨酸甲酯（10⁻³.⁵ M）使两种品种鸡的乙酰胆碱诱导的舒张反应降低程度相似。L⁻精氨酸（10⁻⁴ M）在肉鸡中比来航鸡更能增强乙酰胆碱诱导的舒张反应。对10⁻¹⁰ - 10⁻⁶ M SNP的舒张反应在两个品种之间没有差异，但在较高浓度（10⁻⁵和10⁻⁴ M）时，肉鸡的舒张反应比来航鸡更大（P < 0.05）。PPV（10⁻⁴ M）和SNP（10⁻⁴ M）诱导的最大舒张反应在肉鸡中比来航鸡更大（分别为176.2±14.7%对120.9±14.7%和201.3±7.8%对171.2±10.7%，P < 0.05）。肉鸡的PA环似乎具有增强的内在张力和降低的内皮源性一氧化氮活性，这两者都可能导致肉鸡易患肺动脉高压。
