Kanakis C, Pouget M, Rosen K M
Ann Intern Med. 1979 Oct;91(4):571-4. doi: 10.7326/0003-4819-91-4-571.
We have previously reported that 25 micrograms/kg of intravenous (i.v.) delta-9-tetrahydrocannabinol (delta-9-THC) produces marked increases in heart rate, prolongation of left ventricular ejection time corrected for heart rate (LVETc), and a shortening of the pre-ejection period in normal volunteers. Beta-adrenergic blockade partially attenuates these responses. To elucidate further the mechanism of action of delta-9-THC, we gave 10 normal volunteers 0.1 mg/kg of i.v. propranolol and 2 mg of i.v. atropine before they received 25 micrograms/kg of i.v. delta-9-THC. Systolic time intervals were compared in the denervated subjects before and after delta-9-THC. Post delta-9-THC responses were measured at a time approximating peak psychologic high. Mean +/- SEM heart rate before and after delta-9-THC was 89 +/- 4 and 87 +/- 3 beats/min (NS); mean +/- SEM pre-ejection period before and after delta-9-TCH was 107 +/- 5 and 109 +/- 4 ms (NS); and mean +/- SEM LVETc before and after delta-9-THC was 433 +/- 6 and 429 +/- 6 ms (NS). Since previous denervation of our subjects with atropine and propranolol totally abolished changes in heart rate and systolic time intervals, the cardiac effects of delta-9-THC appear to be mediated totally via the autonomic nervous system, probably reflecting direct central nervous system stimulation.
我们之前报道过，静脉注射25微克/千克的δ-9-四氢大麻酚（δ-9-THC）可使正常志愿者的心率显著增加，校正心率后的左心室射血时间（LVETc）延长，射血前期缩短。β-肾上腺素能阻滞剂可部分减弱这些反应。为了进一步阐明δ-9-THC的作用机制，我们在10名正常志愿者接受25微克/千克静脉注射的δ-9-THC之前，先给他们静脉注射0.1毫克/千克的普萘洛尔和2毫克的阿托品。比较了去神经受试者在注射δ-9-THC前后的收缩期时间间隔。在接近心理兴奋高峰时测量注射δ-9-THC后的反应。注射δ-9-THC前后的平均±标准误心率分别为89±4和87±3次/分钟（无显著性差异）；注射δ-9-THC前后的平均±标准误射血前期分别为107±5和109±4毫秒（无显著性差异）；注射δ-9-THC前后的平均±标准误LVETc分别为433±6和429±6毫秒（无显著性差异）。由于之前用阿托品和普萘洛尔使我们的受试者去神经后完全消除了心率和收缩期时间间隔的变化，因此δ-9-THC的心脏效应似乎完全是通过自主神经系统介导的，可能反映了中枢神经系统的直接刺激。
