大鼠肺迷走神经传入末梢对化学刺激物的敏感性

C.-Y Ho , Q Gu , Y.S Lin , L.-Y Lee
{"title":"大鼠肺迷走神经传入末梢对化学刺激物的敏感性","authors":"C.-Y Ho ,&nbsp;Q Gu ,&nbsp;Y.S Lin ,&nbsp;L.-Y Lee","doi":"10.1016/S0034-5687(01)00241-9","DOIUrl":null,"url":null,"abstract":"<div><p>This study was carried out to investigate the relationship between the conduction velocity of the vagal afferents arising from the rat lungs and their sensitivities to capsaicin, other chemical irritants, and lung inflation. We recorded single-unit activities of vagal pulmonary afferents (<em>n</em>=205) in anesthetized, open-chest rats, and distinguished C fibers (conduction velocity&lt;2 m/sec) from myelinated afferents; the latter group was further classified into rapidly adapting pulmonary receptors (RARs) and slowly adapting pulmonary stretch receptors (SARs) on the basis of their adaptation indexes to lung inflation. Right-atrial injection of capsaicin (1 μg/kg) evoked an abrupt and intense stimulatory effect in 88.9% (64/72) of the pulmonary C fibers tested, but only a mild stimulation in 6.3% (3/48) of the RARs and none of the SARs. Other inhaled and injected chemical stimulants (e.g., cigarette smoke, lactic acid) activated 68.9% (42/61) of the pulmonary C fibers. The same chemical irritants exerted a mild stimulatory effect in only 14.5% (8/55) of the RARs; this subgroup of RARs exhibited a low or no baseline activity, and half of them were located near the hilum. Chemical stimulants had little or no effect on SARs. The response of pulmonary C fibers to lung inflation (tracheal pressure=30 cm H<sub>2</sub>O) was not only extremely weak, but also showed a longer onset latency and an irregular pattern. In a sharp contrast, lung inflation evoked rapid and vigorous discharges in both RARs and SARs. In conclusion, C fibers are the primary type of chemosensitive vagal pulmonary afferents in rat lungs.</p></div>","PeriodicalId":20976,"journal":{"name":"Respiration physiology","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2001-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0034-5687(01)00241-9","citationCount":"207","resultStr":"{\"title\":\"Sensitivity of vagal afferent endings to chemical irritants in the rat lung\",\"authors\":\"C.-Y Ho ,&nbsp;Q Gu ,&nbsp;Y.S Lin ,&nbsp;L.-Y Lee\",\"doi\":\"10.1016/S0034-5687(01)00241-9\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>This study was carried out to investigate the relationship between the conduction velocity of the vagal afferents arising from the rat lungs and their sensitivities to capsaicin, other chemical irritants, and lung inflation. We recorded single-unit activities of vagal pulmonary afferents (<em>n</em>=205) in anesthetized, open-chest rats, and distinguished C fibers (conduction velocity&lt;2 m/sec) from myelinated afferents; the latter group was further classified into rapidly adapting pulmonary receptors (RARs) and slowly adapting pulmonary stretch receptors (SARs) on the basis of their adaptation indexes to lung inflation. Right-atrial injection of capsaicin (1 μg/kg) evoked an abrupt and intense stimulatory effect in 88.9% (64/72) of the pulmonary C fibers tested, but only a mild stimulation in 6.3% (3/48) of the RARs and none of the SARs. Other inhaled and injected chemical stimulants (e.g., cigarette smoke, lactic acid) activated 68.9% (42/61) of the pulmonary C fibers. The same chemical irritants exerted a mild stimulatory effect in only 14.5% (8/55) of the RARs; this subgroup of RARs exhibited a low or no baseline activity, and half of them were located near the hilum. Chemical stimulants had little or no effect on SARs. The response of pulmonary C fibers to lung inflation (tracheal pressure=30 cm H<sub>2</sub>O) was not only extremely weak, but also showed a longer onset latency and an irregular pattern. In a sharp contrast, lung inflation evoked rapid and vigorous discharges in both RARs and SARs. In conclusion, C fibers are the primary type of chemosensitive vagal pulmonary afferents in rat lungs.</p></div>\",\"PeriodicalId\":20976,\"journal\":{\"name\":\"Respiration physiology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2001-09-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://sci-hub-pdf.com/10.1016/S0034-5687(01)00241-9\",\"citationCount\":\"207\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Respiration physiology\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0034568701002419\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Respiration physiology","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0034568701002419","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 207

摘要

本研究旨在探讨由大鼠肺产生的迷走神经传入神经的传导速度与其对辣椒素、其他化学刺激物和肺膨胀的敏感性之间的关系。我们记录了麻醉、开胸大鼠迷走神经肺传入神经(n=205)的单单位活动,并从髓鞘传入神经中区分出C纤维(传导速度为2m /秒);根据对肺膨胀的适应指数,将后者进一步分为快速适应肺受体(RARs)和慢适应肺伸展受体(SARs)。右心房注射辣椒素(1 μg/kg)对88.9%(64/72)的肺C纤维有突然的强烈刺激作用,但对6.3%(3/48)的rar有轻微刺激作用,对SARs无刺激作用。其他吸入和注射的化学刺激物(如香烟烟雾、乳酸)激活68.9%(42/61)的肺C纤维。相同的化学刺激物仅对14.5%(8/55)的RARs产生轻度刺激作用;该亚组RARs表现出较低或无基线活性,其中一半位于门附近。化学兴奋剂对SARs的作用很小或没有作用。肺C纤维对肺充气(气管压=30 cm H2O)的反应极弱,且起病潜伏期较长,形态不规则。与之形成鲜明对比的是,肺膨胀在RARs和SARs中都引起了快速和剧烈的放电。综上所述,C纤维是大鼠肺化学敏感迷走神经传入神经的主要类型。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
Sensitivity of vagal afferent endings to chemical irritants in the rat lung

This study was carried out to investigate the relationship between the conduction velocity of the vagal afferents arising from the rat lungs and their sensitivities to capsaicin, other chemical irritants, and lung inflation. We recorded single-unit activities of vagal pulmonary afferents (n=205) in anesthetized, open-chest rats, and distinguished C fibers (conduction velocity<2 m/sec) from myelinated afferents; the latter group was further classified into rapidly adapting pulmonary receptors (RARs) and slowly adapting pulmonary stretch receptors (SARs) on the basis of their adaptation indexes to lung inflation. Right-atrial injection of capsaicin (1 μg/kg) evoked an abrupt and intense stimulatory effect in 88.9% (64/72) of the pulmonary C fibers tested, but only a mild stimulation in 6.3% (3/48) of the RARs and none of the SARs. Other inhaled and injected chemical stimulants (e.g., cigarette smoke, lactic acid) activated 68.9% (42/61) of the pulmonary C fibers. The same chemical irritants exerted a mild stimulatory effect in only 14.5% (8/55) of the RARs; this subgroup of RARs exhibited a low or no baseline activity, and half of them were located near the hilum. Chemical stimulants had little or no effect on SARs. The response of pulmonary C fibers to lung inflation (tracheal pressure=30 cm H2O) was not only extremely weak, but also showed a longer onset latency and an irregular pattern. In a sharp contrast, lung inflation evoked rapid and vigorous discharges in both RARs and SARs. In conclusion, C fibers are the primary type of chemosensitive vagal pulmonary afferents in rat lungs.

求助全文
通过发布文献求助,成功后即可免费获取论文全文。 去求助
来源期刊
自引率
0.00%
发文量
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信