Jones C E, Thomas J X, Devous M D, Norris C P, Smith E E
Am J Physiol. 1977 Oct;233(4):H438-43. doi: 10.1152/ajpheart.1977.233.4.H438.
Effects of inosine on left ventricular contractile force, circumflex blood flow, heart rate, and arterial pressure were investigated in mongrel dogs. Infusion of 50 ml of 10, 25, or 50 mM inosine into the right atrium over 5 min produced arterial blood inosine concentrations of 20-120 microM. Infusion of inosine concentrations of 10 mM or greater produced statistically significant increases in contractile force and circumflex blood flow (P less than 0.05). The increases in contractile force and circumflex blood flow caused by 50 inosine were approximately 40% and 110%, respectively. No statistically significant increases in heart rate or arterial pressure were observed during infusion of inosine at any concentration. Administration of propranolol (2 mg/kg) in no way altered the effects of inosine on contractile force or circumflex blood flow. Thus, the present study suggests that inosine in concentrations which may be produced in the myocardium during stressful conditions causes a substantial effect on the inotropic state of the heart and that the effects of inosine are not mediated through adrenergic mechanisms.
在杂种犬中研究了肌苷对左心室收缩力、回旋支血流量、心率和动脉血压的影响。在5分钟内将50毫升10、25或50毫摩尔的肌苷注入右心房，使动脉血肌苷浓度达到20 - 120微摩尔。注入10毫摩尔或更高浓度的肌苷会使收缩力和回旋支血流量出现统计学上的显著增加（P < 0.05）。50毫摩尔肌苷引起的收缩力和回旋支血流量增加分别约为40%和110%。在注入任何浓度的肌苷期间，未观察到心率或动脉血压有统计学上的显著增加。给予普萘洛尔（2毫克/千克）丝毫未改变肌苷对收缩力或回旋支血流量的影响。因此，本研究表明，在应激状态下心肌中可能产生的浓度的肌苷会对心脏的变力状态产生实质性影响，并且肌苷的作用不是通过肾上腺素能机制介导的。
