Wong N L, Wong E F, Au G H, Hu D C
Department of Medicine, University of British Columbia, Vancouver, Canada.
Am J Physiol. 1988 Sep;255(3 Pt 1):E260-4. doi: 10.1152/ajpendo.1988.255.3.E260.
The role of intracellular signals in the regulation of atrial natriuretic peptide (ANP) release was studied using the isolated left and right atria from a rat. The atria were perfused with Tyrode's solution, equilibrated with 95% O2-5% CO2 at 37 degrees C with a constant flow of 0.5 ml/min. Addition of epinephrine (10(-6) M), an alpha- and beta-agonist, to the perfusate induced the biphasic release of ANP from the right atrium without effect on the left. The initial peak (19.2 +/- 2.6 pg.min-1.ml-1) occurs 2-4 min after the administration of epinephrine, which lasted 4-6 min and returned to base line (10.4 +/- 1.1 pg.min-1.mg-1). The second peak (16.5 +/- 2.0 pg.min-1.ml-1) appeared 30-35 min after epinephrine administration and was sustained for 100 min, at which time the experiment was terminated. The first peak was stimulated by isoproterenol (10(-6) M), a beta-agonist, and blunted by propranolol (10(-6) M), a beta-antagonist. The second peak appeared following methoxamine (10(-6) M), an alpha-agonist, and could be suppressed by phentolamine (10(-6) M), an alpha-antagonist. These studies indirectly suggest that the adenosine 3',5'-cyclic monophosphate system and the inositol triphosphate system are involved in ANP secretion, with the former responsible for the initial rapid release and the latter maintaining the secretion.
利用大鼠离体的左、右心房，研究了细胞内信号在心房利钠肽（ANP）释放调节中的作用。心房用台氏液灌注，在37℃下用95% O₂-5% CO₂平衡，恒定流速为0.5 ml/min。向灌流液中加入肾上腺素（10⁻⁶ M），一种α和β激动剂，可诱导右心房ANP的双相释放，而对左心房无影响。初始峰值（19.2±2.6 pg·min⁻¹·ml⁻¹）在给予肾上腺素后2-4分钟出现，持续4-6分钟，然后恢复到基线（10.4±1.1 pg·min⁻¹·mg⁻¹）。第二个峰值（16.5±2.0 pg·min⁻¹·ml⁻¹）在给予肾上腺素后30-35分钟出现，并持续100分钟，此时实验终止。第一个峰值由β激动剂异丙肾上腺素（10⁻⁶ M）刺激，并被β拮抗剂普萘洛尔（10⁻⁶ M）减弱。第二个峰值在α激动剂甲氧明（10⁻⁶ M）作用后出现，并可被α拮抗剂酚妥拉明（10⁻⁶ M）抑制。这些研究间接表明，腺苷3',5'-环磷酸系统和肌醇三磷酸系统参与了ANP的分泌，前者负责初始的快速释放，后者维持分泌。
