Nakazawa H, Sekizawa K, Morikawa M, Yamauchi K, Satoh M, Maeyama K, Watanabe T, Sasaki H
Department of Geriatric Medicine, Tohoku University School of Medicine, Sendai, Japan.
Am J Respir Crit Care Med. 1994 May;149(5):1180-5. doi: 10.1164/ajrccm.149.5.8173757.
We investigated the effects of viral respiratory infection by Sendai virus on bronchial responses to aerosolized histamine in anesthetized guinea pigs and on the activity of histamine N-methyltransferase (HMT). We measured the change in total pulmonary resistance induced by histamine in the presence or absence of a specific HMT inhibitor, SKF 91488, in noninfected and infected animals. In the absence of SKF 91488, the bronchoconstrictor response to histamine was greater in infected than in noninfected animals. SKF 91488 (10(-2) M, 90 breaths) potentiated the responses to histamine in noninfected animals, and the magnitude of augmented responses to histamine by SKF 91488 was similar to that by viral infection. Furthermore, SKF 91488 did not further potentiate the responses to histamine in infected animals. However, responses to aerosolized acetylcholine were unaffected by viral infection and SKF 91488. The HMT activity decreased by 56% in the trachea, 86% in the bronchi, and 52% in the parenchymal tissue in the infected animals. In contrast to HMT activity, acetylcholinesterase activity was unaffected by viral infection. These results suggest that respiratory infection by Sendai virus causes enhanced bronchial responsiveness to histamine by decreasing HMT activity in airways.
我们研究了仙台病毒引起的病毒性呼吸道感染对麻醉豚鼠支气管对雾化组胺的反应以及组胺N - 甲基转移酶（HMT）活性的影响。我们测量了在有无特异性HMT抑制剂SKF 91488的情况下，未感染和感染动物中组胺诱导的总肺阻力变化。在没有SKF 91488的情况下，感染动物对组胺的支气管收缩反应比未感染动物更强。SKF 91488（10⁻² M，90次呼吸）增强了未感染动物对组胺的反应，且SKF 91488增强的组胺反应幅度与病毒感染相似。此外，SKF 91488并未进一步增强感染动物对组胺的反应。然而，对雾化乙酰胆碱的反应不受病毒感染和SKF 91488的影响。感染动物的气管中HMT活性降低了56%，支气管中降低了86%，实质组织中降低了52%。与HMT活性相反，乙酰胆碱酯酶活性不受病毒感染影响。这些结果表明，仙台病毒引起的呼吸道感染通过降低气道中的HMT活性导致支气管对组胺的反应性增强。
