Transient receptor potential ankyrin 1 （TRPA1） is a key player in pain and neurogenic inflammation, and is localized in nociceptive primary sensory dorsal root ganglion （DRG） neurons. TRPA1 plays a major role in t...Transient receptor potential ankyrin 1 （TRPA1） is a key player in pain and neurogenic inflammation, and is localized in nociceptive primary sensory dorsal root ganglion （DRG） neurons. TRPA1 plays a major role in the transmission of nociceptive sensory signals. The generation of neurogenic inflammation appears to involve TRPAl-evoked release of calcitonin gene-related peptide （CGRP）. However, it remains unknown whether TRPA1 or CGRP expression is affected by TRPA 1 activation. Thus, in this study, we examined TRPA 1 and CGRP expression in DRG neurons in vitro after treatment with the TRPA1 activator tbrmaldehyde or the TRPA1 blocker menthol. In addition, we examined the role of extracellular signal-regulated protein kinase 1/2 （ERK1/2） in this process. DRG neurons in culture were exposed to formaldehyde, menthol, the ERK1/2 inhibitor PD98059 ＋ formaldehyde, or PD98059 ＋ menthol. After treatment, real-time polymerase chain reaction, western blot assay and double immunofluorescence labeling were performed to evaluate TRPA1 and CGRP expression in DRG neurons. Formaldehyde elevated mRNA and protein levels of TRPA 1 and CGRP, as well as the proportion of TRPA1- and CGRP-positive neurons. In contrast, menthol reduced TRPA1 and CGRP expression. Furthermore, the effects of lbrmaldehyde, but not menthol, on CGRP expression were blocked by pretreatment with PD98059. PD98059 pretreatment did not affect TRPA1 expression in the presence of formaldehyde or menthol.展开更多
基金supported by the National Natural Science Foundation of China,No.81501935(to HL)the Natural Science Foundation of Shandong Province of China,No.ZR2014HQ065(to HL)
文摘Transient receptor potential ankyrin 1 （TRPA1） is a key player in pain and neurogenic inflammation, and is localized in nociceptive primary sensory dorsal root ganglion （DRG） neurons. TRPA1 plays a major role in the transmission of nociceptive sensory signals. The generation of neurogenic inflammation appears to involve TRPAl-evoked release of calcitonin gene-related peptide （CGRP）. However, it remains unknown whether TRPA1 or CGRP expression is affected by TRPA 1 activation. Thus, in this study, we examined TRPA 1 and CGRP expression in DRG neurons in vitro after treatment with the TRPA1 activator tbrmaldehyde or the TRPA1 blocker menthol. In addition, we examined the role of extracellular signal-regulated protein kinase 1/2 （ERK1/2） in this process. DRG neurons in culture were exposed to formaldehyde, menthol, the ERK1/2 inhibitor PD98059 ＋ formaldehyde, or PD98059 ＋ menthol. After treatment, real-time polymerase chain reaction, western blot assay and double immunofluorescence labeling were performed to evaluate TRPA1 and CGRP expression in DRG neurons. Formaldehyde elevated mRNA and protein levels of TRPA 1 and CGRP, as well as the proportion of TRPA1- and CGRP-positive neurons. In contrast, menthol reduced TRPA1 and CGRP expression. Furthermore, the effects of lbrmaldehyde, but not menthol, on CGRP expression were blocked by pretreatment with PD98059. PD98059 pretreatment did not affect TRPA1 expression in the presence of formaldehyde or menthol.
