Lou Y P, Lundberg J M
Department of Pharmacology, Karolinska Institute, Stockholm, Sweden.
Biochem Biophys Res Commun. 1992 Nov 30;189(1):537-44. doi: 10.1016/0006-291x(92)91591-d.
Low pH is a well known sensory irritant in pathological conditions such as inflammation. The mechanisms underlying this low pH effect were therefore studied in the guinea pig. Acid exposure caused marked nasal irritation via a specific subset of sensory nerves sensitive to capsaicin. Furthermore, acid caused bronchoconstriction via release of neuropeptides from capsaicin sensitive afferents. Interestingly, capsazepine, a recently developed competitive capsaicin receptor antagonist, selectively inhibited these responses to low pH. Ruthenium red, which blocks the cation channel associated with the capsaicin receptor, had effects similar to those of capsazepine. Therefore, acid irritation of the airway mucosa may involve capsaicin-receptor mechanisms and capsazepine represents a novel protective agent.
低pH值是炎症等病理状况下一种众所周知的感觉刺激物。因此，在豚鼠身上研究了这种低pH值效应的潜在机制。酸暴露通过对辣椒素敏感的特定感觉神经亚群引起明显的鼻部刺激。此外，酸通过辣椒素敏感传入神经释放神经肽导致支气管收缩。有趣的是，辣椒平（一种最近开发的竞争性辣椒素受体拮抗剂）选择性地抑制了对低pH值的这些反应。钌红可阻断与辣椒素受体相关的阳离子通道，其作用与辣椒平相似。因此，气道黏膜的酸刺激可能涉及辣椒素受体机制，辣椒平代表一种新型的保护剂。
