Cardiac atria are the primary source of ANP release in hypoxia-adapted rats

LIFE SCIENCES

卷:87

Article

Casserly, Brian^2,4  Pietras, Linda¹  Schuyler, Joy³  Wang, Richard³  Hill, Nicholas S.⁵  Klinger, James R.^1,4 

[1] Rhode Isl Hosp, Div Pulm Sleep & Crit Care Med, Providence, RI 02903 USA

[2] Brown Univ, Mem Hosp Rhode Isl, Div Pulm Med, Pawtucket, RI 02860 USA

[3] Rhode Isl Hosp, Dept Emergency Med, Providence, RI 02903 USA

[4] Brown Univ, Alpert Med Sch, Providence, RI 02912 USA

[5] Tufts Univ New England Med Ctr, Div Pulm Sleep & Crit Care Med, Boston, MA USA

关键词: Atrial natriuretic peptide (ANP);    Hypoxic pulmonary hypertension;    Isolated perfused heart;    Cardiac atria;    Hypoxia;   

DOI  :  10.1016/j.lfs.2010.07.013

来源: Elsevier

【 摘 要 】

Aims: Atrial natriuretic peptide (ANP) is released from the heart in response to hypoxia and helps mitigate the development of pulmonary hypertension. However, the mechanism of hypoxia-induced ANP release is not clear. The cardiac atria are the primary source of ANP secretion under normal conditions, but right ventricular ANP expression is markedly up-regulated during adaptation to hypoxia. We sought to better understand mechanisms of cardiac ANP release during adaptation to hypoxia. Main methods: We measured hypoxia-induced ANP release from isolated perfused rat hearts obtained from normoxia and hypoxia-adapted rats before and after removal of the atria. Key findings: In both normoxia- and hypoxia-adapted hearts. ANP levels in the perfusate increased within 15 min of hypoxia. Hypoxia-induced ANP release was greater from hypoxia-adapted than normoxia-adapted hearts. Baseline and hypoxia-induced ANP release were considerably greater with the atria intact (213 +/- 29 to 454 +/- 62 and 281 +/- 26 to 618 +/- 87 pg/ml for normoxia- and hypoxia-adapted hearts respectively. P<0.001 for both) than with atria removed (94 +/- 17 to 131 +/- 32 and 103 +/- 26 to 201 +/- 55 pg/ml, respectively, P<0.002 for both). Hypoxia-induced ANP release was reduced over 80% by removing the atria in both normoxia- and in hypoxia-adapted hearts. Acute hypoxia caused a transient increase in lactate release and reductions in pH and left ventricular generated force, but no differences in pH or left ventricular generated force were seen between normoxia- and hypoxia-adapted rats. Significance: We conclude that the right ventricle is not a major source of cardiac ANP release in normoxia- or hypoxia-adapted rats. (C) 2010 Elsevier Inc. All rights reserved.

【 授权许可】

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