Inhibition of Neurogenic Inflammation by the Amazonian Herbal Medicine Sangre de Grado

This study was designed to determine if the Amazonian medicinal sangre de grado, confers benefit by suppressing the activation of sensory afferent nerves. Methods: (i) vasorelaxation of rat mesenteric arteries in response to calcitonin gene-related peptide; (ii) rat paw edema in response to protease-activating peptide receptor 2–activating peptide; (iii) rat paw hyperalgesia in response to low-dose protease-activating peptide receptor 2–activating peptide or prostaglandin E2; (iv) gastric hyperemia in response luminal capsaicin; (v) a clinical trial of a sangre de grado balm in pest control workers. The parent botanical was fractionated for evaluation of potential active components. In preconstricted rat mesenteric arteries, highly diluted sangre de grado (1:10,000) caused a shift to the right of the calcitonin gene-related peptide dose–response curve (p