Stereo-selective inhibition of transient receptor potential TRPC5 cation channels by neuroactive steroids
| العنوان: | Stereo-selective inhibition of transient receptor potential TRPC5 cation channels by neuroactive steroids |
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| المؤلفون: | Majeed, Y, Amer, MS, Agarwal, AK, McKeown, L, Porter, KE, O'Regan, DJ, Naylor, J, Fishwick, CWG, Muraki, K, Beech, DJ |
| المصدر: | British Journal of Pharmacology |
| بيانات النشر: | Blackwell Science Inc, 2011. |
| سنة النشر: | 2011 |
| مصطلحات موضوعية: | Patch-Clamp Techniques, Estradiol, Myocytes, Smooth Muscle, Dihydrotestosterone, Stereoisomerism, cationic channel, progesterone, Research Papers, transient receptor potential canonical 5, Structure-Activity Relationship, HEK293 Cells, Sphingosine, Pregnenolone, neurosteroid, Humans, Calcium, Lysophospholipids, Gonadal Steroid Hormones, Cells, Cultured, Phospholipids, TRPC Cation Channels |
| الوصف: | BACKGROUND AND PURPOSE Transient receptor potential canonical 5 (TRPC5) channels are widely expressed, including in the CNS, where they potentiate fear responses. They also contribute to other non-selective cation channels that are stimulated by G-protein-coupled receptor agonists and lipid and redox factors. Steroids are known to modulate fear and anxiety states, and we therefore investigated whether TRPC5 exhibited sensitivity to steroids. EXPERIMENTAL APPROACH Human TRPC5 channels were conditionally expressed in HEK293 cells and studied using intracellular Ca2+ measurement, whole-cell voltage-clamp and excised patch techniques. For comparison, control experiments were performed with cells lacking TRPC5 channels or expressing another TRP channel, TRPM2. Native TRPC channel activity was recorded from vascular smooth muscle cells. KEY RESULTS Extracellular application of pregnenolone sulphate, pregnanolone sulphate, pregnanolone, progesterone or dihydrotestosterone inhibited TRPC5 activity within 1–2 min. Dehydroepiandrosterone sulphate or 17β-oestradiol had weak inhibitory effects. Pregnenolone, and allopregnanolone, a progesterone metabolite and stereo-isomer of pregnanolone, all had no effects. Progesterone was the most potent of the steroids, especially against TRPC5 channel activity evoked by sphingosine-1-phosphate. In outside-out patch recordings, bath-applied progesterone and dihydrotestosterone had strong and reversible effects, suggesting relatively direct mechanisms of action. Progesterone inhibited native TRPC5-containing channel activity, evoked by oxidized phospholipid. CONCLUSIONS AND IMPLICATIONS Our data suggest that TRPC5 channels are susceptible to relatively direct and rapid stereo-selective steroid modulation, leading to channel inhibition. The study adds to growing appreciation of TRP channels as non-genomic steroid sensors. |
| اللغة: | English |
| تدمد: | 1476-5381 0007-1188 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=pmid________::4865dc0d729773c848d142cc56d43937Test http://europepmc.org/articles/PMC3057289Test |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.pmid..........4865dc0d729773c848d142cc56d43937 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 14765381 00071188 |
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