Shortly after the identification of the EDRF, it was suspected that the endothelium could release more than one relaxing factor, depending on the vessel size, the stimulus, and the species studied. Initial studies showed that some vasodilators produce hyperpolarization of the vascular smooth muscle membrane in an endothelium-dependent manner. It is now clear that this is due to the release of a hyperpolarizing factor from the endothelium that is almost certainly different than NO86 Its production is stimulated by many of the same stimuli that evoke the release of NO and depends on intracellular calcium. Although there is some debate regarding the nature of this factor, increasing evidence suggests that it is a cytochrome P450 metabolite of arachidonic acid and perhaps other fatty acids.87 This epoxide, when released from the endothelium, opens calcium-activated potassium channels in the adjacent vascular smooth muscle, resulting in vasodilation.88 It has also been shown that these epoxides have important anti-inflammatory effects.89
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Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.