{"title":"大鼠背根神经节结肠感觉神经元辣椒素敏感性和电压门控钠电流。","authors":"X Su, R E Wachtel, G F Gebhart","doi":"10.1152/ajpgi.1999.277.6.G1180","DOIUrl":null,"url":null,"abstract":"<p><p>DiI-labeled colon sensory neurons were acutely dissociated from S1 rat dorsal root ganglia (DRG) and studied using perforated whole cell patch-clamp techniques. Forty-six percent (54/116) of labeled sensory neurons responded to capsaicin (10(-8)- 10(-5) M) with an increase in inward current, which was a nonspecific cation conductance. Responses to capsaicin applied by puffer ejection were dependent on dose, with a half-maximal response at 4.9 x 10(-7) M; bath application was characterized by marked desensitization. Voltage-gated Na(+) currents in 23 of 30 DRG cells exhibited both TTX-sensitive and TTX-resistant components. In these cells, capsaicin induced an inward current in 11 of 17 cells tested. Of the cells containing only a TTX-sensitive component, none of six cells tested was sensitive to capsaicin. In all cells that responded to capsaicin with an increase in inward current, capsaicin abolished voltage-gated Na(+) currents (n = 21). Capsazepine (10(-6) M) significantly attenuated both the increase in inward current and the reduction in Na(+) currents. Na(+) currents were not significantly altered by adenosine, bradykinin, histamine, PGE(2), or serotonin at 10(-6) M and 10(-5) M. These findings may have important implications for understanding both the irritant and analgesic properties of capsaicin.</p>","PeriodicalId":7590,"journal":{"name":"American Journal of Physiology","volume":"277 6","pages":"G1180-8"},"PeriodicalIF":0.0000,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1152/ajpgi.1999.277.6.G1180","citationCount":"103","resultStr":"{\"title\":\"Capsaicin sensitivity and voltage-gated sodium currents in colon sensory neurons from rat dorsal root ganglia.\",\"authors\":\"X Su, R E Wachtel, G F Gebhart\",\"doi\":\"10.1152/ajpgi.1999.277.6.G1180\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>DiI-labeled colon sensory neurons were acutely dissociated from S1 rat dorsal root ganglia (DRG) and studied using perforated whole cell patch-clamp techniques. Forty-six percent (54/116) of labeled sensory neurons responded to capsaicin (10(-8)- 10(-5) M) with an increase in inward current, which was a nonspecific cation conductance. Responses to capsaicin applied by puffer ejection were dependent on dose, with a half-maximal response at 4.9 x 10(-7) M; bath application was characterized by marked desensitization. Voltage-gated Na(+) currents in 23 of 30 DRG cells exhibited both TTX-sensitive and TTX-resistant components. In these cells, capsaicin induced an inward current in 11 of 17 cells tested. Of the cells containing only a TTX-sensitive component, none of six cells tested was sensitive to capsaicin. In all cells that responded to capsaicin with an increase in inward current, capsaicin abolished voltage-gated Na(+) currents (n = 21). Capsazepine (10(-6) M) significantly attenuated both the increase in inward current and the reduction in Na(+) currents. Na(+) currents were not significantly altered by adenosine, bradykinin, histamine, PGE(2), or serotonin at 10(-6) M and 10(-5) M. These findings may have important implications for understanding both the irritant and analgesic properties of capsaicin.</p>\",\"PeriodicalId\":7590,\"journal\":{\"name\":\"American Journal of Physiology\",\"volume\":\"277 6\",\"pages\":\"G1180-8\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"1999-12-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://sci-hub-pdf.com/10.1152/ajpgi.1999.277.6.G1180\",\"citationCount\":\"103\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"American Journal of Physiology\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1152/ajpgi.1999.277.6.G1180\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"American Journal of Physiology","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1152/ajpgi.1999.277.6.G1180","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 103
摘要
采用全细胞穿孔膜片钳技术,从S1大鼠背根神经节(DRG)急性分离dii标记的结肠感觉神经元。46%(54/116)的标记感觉神经元对辣椒素(10(-8)- 10(-5)M)有反应,向内电流增加,这是一种非特异性阳离子电导。对辣椒素的反应依赖于剂量,在4.9 x 10(-7) M时有半最大反应;浴液应用的特点是显着脱敏。在30个DRG细胞中,23个细胞的电压门控Na(+)电流同时表现出ttx敏感和ttx抗性成分。在这些细胞中,辣椒素在17个测试细胞中的11个中诱导了内向电流。在只含有ttx敏感成分的细胞中,6个细胞对辣椒素都不敏感。在所有对辣椒素有向内电流增加反应的细胞中,辣椒素消除了电压门控的Na(+)电流(n = 21)。Capsazepine (10(-6) M)显著减弱了向内电流的增加和Na(+)电流的减少。在10(-6)M和10(-5)M时,腺苷、缓激肽、组胺、PGE(2)或血清素对Na(+)电流没有显著改变。这些发现可能对理解辣椒素的刺激和镇痛特性具有重要意义。
Capsaicin sensitivity and voltage-gated sodium currents in colon sensory neurons from rat dorsal root ganglia.
DiI-labeled colon sensory neurons were acutely dissociated from S1 rat dorsal root ganglia (DRG) and studied using perforated whole cell patch-clamp techniques. Forty-six percent (54/116) of labeled sensory neurons responded to capsaicin (10(-8)- 10(-5) M) with an increase in inward current, which was a nonspecific cation conductance. Responses to capsaicin applied by puffer ejection were dependent on dose, with a half-maximal response at 4.9 x 10(-7) M; bath application was characterized by marked desensitization. Voltage-gated Na(+) currents in 23 of 30 DRG cells exhibited both TTX-sensitive and TTX-resistant components. In these cells, capsaicin induced an inward current in 11 of 17 cells tested. Of the cells containing only a TTX-sensitive component, none of six cells tested was sensitive to capsaicin. In all cells that responded to capsaicin with an increase in inward current, capsaicin abolished voltage-gated Na(+) currents (n = 21). Capsazepine (10(-6) M) significantly attenuated both the increase in inward current and the reduction in Na(+) currents. Na(+) currents were not significantly altered by adenosine, bradykinin, histamine, PGE(2), or serotonin at 10(-6) M and 10(-5) M. These findings may have important implications for understanding both the irritant and analgesic properties of capsaicin.