Pulmonary Inflammation — A Balancing Act

Abstract

Even in antiquity it was known that inflammation has both beneficial and adverse effects, but only recently have we begun to elucidate how the body maintains a balance between host defenses and tissue injury. This balance is especially important in the lung, where despite protective mechanical and physical forces, noxious agents constantly assault lower respiratory epithelial surfaces.More than 25 years ago, the importance of neurogenic control of pulmonary inflammation was suggested by a study of a tachykinin neuropeptide called substance P.¹ Ablation of substance P–producing sensory neurons by capsaicin, the irritant agent in hot pepper, markedly inhibited the noxious . . .