Dusser D J, Jacoby D B, Djokic T D, Rubinstein I, Borson D B, Nadel J A
Cardiovascular Research Institute, University of California, San Francisco 94143.
J Appl Physiol (1985). 1989 Oct;67(4):1504-11. doi: 10.1152/jappl.1989.67.4.1504.
We examined the effects of viral respiratory infection by Sendai virus on airway responsiveness to tachykinins in guinea pigs. We measured the change in total pulmonary resistance induced by substance P or capsaicin in the presence or absence of the neutral endopeptidase inhibitor, phosphoramidon, in infected and in noninfected animals. In the absence of phosphoramidon, the bronchoconstrictor responses to substance P and to capsaicin were greater in infected than in noninfected animals. Phosphoramidon did not further potentiate the responses to substance P and to capsaicin in the infected animals, whereas it did so in noninfected animals. Studies performed in vitro showed that nonadrenergic noncholinergic bronchial smooth muscle responses to electrical field stimulation were also increased in tissues from infected animals and that phosphoramidon increased the response of tissues from noninfected animals greatly but increased the responses of tissues from infected animals only slightly. Responses to acetylcholine were unaffected by viral infection. Neutral endopeptidase activity was decreased by 40% in the tracheal epithelial layer of the infected animals. We suggest that respiratory infection by Sendai virus causes enhanced airway responsiveness to tachykinins by decreasing neutral endopeptidase-like activity in the airway epithelium.
我们研究了仙台病毒引起的病毒性呼吸道感染对豚鼠气道对速激肽反应性的影响。我们在感染和未感染的动物中，测量了在存在或不存在中性内肽酶抑制剂磷酰胺素的情况下，P物质或辣椒素诱导的总肺阻力变化。在不存在磷酰胺素的情况下，感染动物对P物质和辣椒素的支气管收缩反应比未感染动物更强。磷酰胺素在感染动物中并未进一步增强对P物质和辣椒素的反应，而在未感染动物中则会增强。体外研究表明，感染动物组织中对电场刺激的非肾上腺素能非胆碱能支气管平滑肌反应也增加，并且磷酰胺素极大地增加了未感染动物组织的反应，但仅略微增加了感染动物组织的反应。对乙酰胆碱的反应不受病毒感染的影响。感染动物气管上皮层中的中性内肽酶活性降低了40%。我们认为，仙台病毒引起的呼吸道感染通过降低气道上皮中类中性内肽酶活性，导致气道对速激肽的反应性增强。
