کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6277321 | 1295754 | 2010 | 8 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Serotonin upregulates low- and high-threshold tetrodotoxin-resistant sodium channels in the same subpopulation of rat nociceptors
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
5-HTDRGGTPHEPESNav1.9EGTANav1.8TTXtetraethylammonium chloridedorsal root ganglion - گانگلیون ریشه پشتی4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid - 4- (2-hydroxyethyl) -1-piperazineethanesulfonic acidethylene glycol tetraacetic acid - اتیلن گلیکول تتراستیک اسیدtetrodotoxin - تترو دوتوکسین holding potential - داشتن پتانسیلSerotonin - سروتونینSensory Neuron - نورون حسیTetraethylammonium hydroxide - هیدروکسید تترا اتیل آمونیومHyperalgesia - پردردی یا هایپرآلژزیTEA - چایGuanosine triphosphate - گوانوزین تری فسفات
موضوعات مرتبط
علوم زیستی و بیوفناوری
علم عصب شناسی
علوم اعصاب (عمومی)
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
The modulation by serotonin (5-HT) of low- and high-threshold tetrodotoxin- (TTX) resistant Na+ currents was studied in small-diameter (â25 μm) acutely-isolated rat dorsal root ganglion (DRG) cells. Each DRG cell included in the study was classified as type 2 or non-type 2, based on expression of a low-threshold A-type K+ current. When cells of either type were recorded from using a CsF based internal solution and a holding potential (HP) of â80 mV, the apparent threshold for activation of TTX-resistant Na+ currents ranged from â75 to â60 mV. A 500 ms prepulse to â60 mV greatly suppressed currents evoked by test potentials (TPs) to â75 through â35 mV. A similar scenario was observed when the CsF based internal solution was changed for one that contained CsCl, except that the apparent threshold of activation was shifted by about +25 mV, and currents evoked by TPs to â55 to â35 mV in the absence of a prepulse were much smaller than their counterparts observed with the CsF internal. These data suggest two types of TTX-resistant Na+ currents; one with a low-threshold for activation that is enhanced by the presence of fluoride inside the cell and is inactivated by holding at â60 mV, and one with a higher threshold for activation that is not inactivated by holding at â60 mV. In type 2 DRG cells, 10 μM 5-HT upregulated low-threshold currents evoked by TPs to â55 to â35 mV from HP â80 mV, as well as high-threshold currents evoked by more depolarized TPs from HP â60 mV. However, when cells were held at â60 mV, 5-HT did not upregulate currents evoked by TPs to â35 or â30 mV, suggesting that the low-threshold current was nearly completely inactivated. Previous studies have suggested that type 2 DRG cells are nociceptor cell bodies. If 5-HT produces similar effects in type 2 DRG cell peripheral receptors, the upregulation of the low-threshold currents may serve to lower the threshold for nociception, while the upregulation of the high-threshold current may strengthen nociceptive signals.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Neuroscience - Volume 165, Issue 4, 17 February 2010, Pages 1293-1300
Journal: Neuroscience - Volume 165, Issue 4, 17 February 2010, Pages 1293-1300
نویسندگان
R.S. Scroggs,