概括
德尔塔-9-四大麻 (delta-9-THC) 通过增加心率和改变心缩时间间隔,显著提高心脏表现. β抑制剂部分抑制了这些心血管效应.
科学领域:
- 心脏病学 心脏病学
- 药理学 药理学是指药理学的学科.
- 身体生理学 身体生理学
背景情况:
- 作为大麻的主要精神活性成分的delta-9-tetrahydrocannabinol (delta-9-THC) 已知对心血管有影响.
- 了解delta-9-THC对心脏功能的确切影响对于评估其生理后果至关重要.
研究的目的:
- 在健康的男性志愿者中研究静脉注射delta-9-THC对缩时间间隔 (STI) 的影响.
- 确定β-上腺体阻断在调节对delta-9-THC的心脏反应中的作用.
主要方法:
- 系统性时间间隔 (STI) 在静脉注射25毫克/公斤delta-9-THC之前和之后测量了十名健康的男性志愿者.
- 测量重复在9个额外的受试者谁接受了之前的β-上腺素阻塞.
主要成果:
- 德尔塔-9-THC显著增加了心率 (32 +/- 7次/分钟) 和改变了STI,包括延长了总电机学心 (17 +/- 4.2毫秒) 和左心室喷射时间 (LVETc) (24 +/- 4.0毫秒).
- 预喷射期 (PEP) 被delta-9-THC (17+/- 5.1毫秒) 显著缩短.
- β-上腺素阻塞减弱了这些效应,特别是防止了PEP的显著缩短.
结论:
- 德尔塔-9-THC增强心脏表现,通过心率增加和修饰性性传播疾病证明,而不会改变血压或后负荷.
- β-上腺素通路在调解delta-9-THC对心脏的影响方面起着部分作用.
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