Differential effects of acute hypoxia on the activation of TRPV1 by capsaicin and acidic pH
- Authors
- Kim, KS[Kim, Kyung Soo]; Yoo, HY[Yoo, Hae Young]; Park, KS[Park, Kyung Sun]; Kim, JK[Kim, Jin Kyoung]; Zhang, YH[Zhang, Yin-Hua]; Kim, SJ[Kim, Sung Joon]
- Issue Date
- Mar-2012
- Publisher
- SPRINGER TOKYO
- Citation
- JOURNAL OF PHYSIOLOGICAL SCIENCES, v.62, no.2, pp.93 - 103
- Indexed
- SCIE
SCOPUS
- Journal Title
- JOURNAL OF PHYSIOLOGICAL SCIENCES
- Volume
- 62
- Number
- 2
- Start Page
- 93
- End Page
- 103
- URI
- https://scholarworks.bwise.kr/skku/handle/2021.sw.skku/66156
- DOI
- 10.1007/s12576-011-0185-4
- ISSN
- 1880-6546
- Abstract
- Transient receptor potential vanilloid 1 (TRPV1) is a Ca2+-permeable cation channel activated by a variety of physicochemical stimuli. The effect of hypoxia (P-O2, 3%) on rat TRPV1 overexpressed in HEK293T has been studied. The basal TRPV1 current (I (TRPV1)) was partly activated by hypoxia, whereas capsaicin-induced TRPV1 (I (TRPV1,Cap)) was attenuated. Such changes were also suggested from hypoxia- and capsaicin-induced Ca2+ signals in TRPV1-expressing cells. Regarding plausible changes of reactive oxygen species (ROS) under hypoxia, the effects of antioxidants, vitamin C and tiron, as membrane-impermeable and -permeable, respectively, were tested. Both I (TRPV1) and I (TRPV1,Cap) were increased by vitamin C, while only I (TRPV1) was slightly increased by tiron. The hypoxic inhibition of I (TRPV1,Cap) was still persistent under hypoxia/vitamin C. Interestingly, hypoxia/tiron strongly inhibited both I (TRPV1) and I (TRPV1,Cap). Also, with vitamin C applied through a pipette solution, hypoxia inhibited I (TRPV1) and I (TRPV1,Cap). In contrast, hypoxia and hypoxia/tiron had no effect on the I (TRPV1) induced by acid (pH 6.2, I (TRPV1,Acid)). Taken together, hypoxia partly activated TRPV1 while it decreased their sensitivity to capsaicin. Putative changes of ROS under hypoxia might underlie the side-specific effects of ROS on TRPV1: inhibitory at the extracellular and stimulatory at the intracellular side, respectively. The differential effects of hypoxia on I (TRPV1,Cap) and I (TRPV1,Acid) suggested that the intracellular ROS increase might attenuate the pharmacological potency of capsaicin.
- Files in This Item
- There are no files associated with this item.
- Appears in
Collections - Medicine > Department of Medicine > 1. Journal Articles
Items in ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.