Ralevic Vera, Kendall David A, Randall Michael D, Smart Darren
School of Biomedical Sciences, University of Nottingham Medical School, Queen's Medical Centre, UK.
Life Sci. 2002 Oct 18;71(22):2577-94. doi: 10.1016/s0024-3205(02)02086-6.
Capsaicin-sensitive sensory nerves are widely distributed in the cardiovascular system. They are activated by a variety of physical and chemical stimuli, characteristically by capsaicin acting via the vanilloid receptor VR1, and have a role in the regulation of peripheral vascular resistance and maintenance of homeostasis via their afferent and efferent functions. Cannabinoids, a recently discovered family of extracellular signalling molecules, can act at cannabinoid (CB) receptors expressed on sensory nerves, to cause inhibition of sensory neurotransmitter release. There is recent evidence, however, that anandamide, an endogenous cannabinoid, can activate VR1, coexpressed with CB receptors on the same sensory nerve terminals, causing a release of sensory neurotransmitter, vasorelaxation and hypotension. Hence, anandamide can elicit opposite actions, inhibition via CB receptors and excitation via VR1, on sensory neurotransmission. The possible biological significance of this is discussed.
对辣椒素敏感的感觉神经广泛分布于心血管系统。它们可被多种物理和化学刺激激活，典型的是通过辣椒素作用于香草酸受体VR1来激活，并且通过其传入和传出功能在调节外周血管阻力和维持体内平衡方面发挥作用。大麻素是最近发现的一类细胞外信号分子，可作用于感觉神经上表达的大麻素（CB）受体，从而抑制感觉神经递质的释放。然而，最近有证据表明，内源性大麻素花生四烯乙醇胺可激活与CB受体在同一感觉神经末梢共表达的VR1，导致感觉神经递质释放、血管舒张和低血压。因此，花生四烯乙醇胺可对感觉神经传递产生相反的作用，即通过CB受体产生抑制作用，通过VR1产生兴奋作用。本文讨论了其可能的生物学意义。
