Mechanisms whereby Propofol Mediates Peripheral Vasolidation in Humans: Sympathoinhibition or Direct Vascular Relaxation?

@article{Robinson1997MechanismsWP,
  title={Mechanisms whereby Propofol Mediates Peripheral Vasolidation in Humans: Sympathoinhibition or Direct Vascular Relaxation?},
  author={Brian J. Robinson and Thomas J. Ebert and Timothy J. O'Brien and M D Colinco and Michael Muzi},
  journal={Anesthesiology},
  year={1997},
  volume={86},
  pages={64–72}
}
Background Anesthetic induction and maintenance with propofol are associated with decreased blood pressure that is, in part, due to decreased peripheral resistance. Several possible mechanisms whereby propofol could reduce peripheral resistance include a direct action of propofol on vascular smooth muscle, an inhibition of sympathetic activity to the vasculature, or both. This study examined these two possibilities in humans by measuring the forearm vascular responses to infusions of propofol… 
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One mechanism promoting hypotension during propofol anesthesia in humans seems to be related to its direct effects on venous smooth muscle tone and presumably venous return.
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TLDR
It is demonstrated that clinically relevant concentrations of propofol (10(-6) M or less) have no direct vasodilator effects and that it reduces endothelium-dependent relaxation to acetylcholine.
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TLDR
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TLDR
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TLDR
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TLDR
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