RESUMO
Objective: To evaluate the effects of penehyclidine hydrochloride on the nuclear factor erythroid 2-related factor 2/antioxidant responsive element (Nrf2/ARE) signaling pathway during endotoxin-induced acute lung injury(ALI) in neonate rats. Methods: Forty 7-day-old Wistar rats weighing 12-18 g were randomly divided into 4 groups (n=10) using a random number table: normal saline group(NS group), acute lung injury(ALI group), penehyclidine hydrochloride group(PHC group) and penehyclidine hydrochloride+ Nrf2 siRNA plasmid group(PNS group). The ALI model was induced with intraperitoneal endotoxin (5.0 mg/kg) in groups ALI, PHC and PNS. In groups PHC and PNS, penehyclidine hydrochloride (2.0 mg/kg) was injected intraperitoneally at 1 h before ALI respectively, while the equal volume of normal saline was administered in groups NS and ALI. The animal of PNS group were inhaled adenovirus packaging of Nrf2-siRNA three times (one time a day) before modeling. At 4 h after endotoxin injection, the rats were sacrificed. The lungs were collected to determine the wet/dry(W/D) lung weight ratio. The expression of Nrf2 and heme oxygen and enzyme 1(HO-1) were determined by Western blotting, contents of tumor necrosis factor-alpha(TNF-α),interleukin10 (IL-10)were determined by enzyme-linked immunosorbent assay(ELISA). The cell apoptosis were determined by transferase-mediated deoxyuridine triphosphate-biotin nick end labeling(TUNEL),and the apoptotic index was calculated. Results: The W/D ratio in NS, ALI, PHC and PNS groups were (4.2±0.1), (9.6±0.7), (6.5±0.6), (8.3±1.3) respectively. The apoptotic index were (3.7±0.5)%, (31.5±3.2)%, (17.6±4.2)%, (28.1±3.5)%respectively.The contents of TNF-α were (10.3±1.6), (98.5±8.5), (68.5±6.7), (89.9±8.5) pg/ml respectively. The contents of IL-10 were (7.9±0.6), (102.8±9.3), (72.5±5.8), (97.7±9.1) pg/ml respectively.The expression of Nrf2 were (23.2±7.6), (79.8±13.0), (155.5±16.7), (12.0±3.3) respectively. The expression of HO-1 were (31.7±8.6), (90.8±10.3), (147.6±22.5), (61.4±9.7) respectively. There were statistically significant differences among different groups (F=86.013, 154.897, 328.810, 374.198, 333.965, 125.274, all P<0.05). Compared with group NS, the W/D ratio, apoptotic index and the contents of TNF-α, IL-10 increased, the expression of Nrf2 and HO-1 up-regulated in group ALI and group PHC (all P<0.05). Compared with group ALI, the W/D ratio, apoptotic index and the contents of TNF-α, IL-10 decreased, the expression of Nrf2 and HO-1 up-regulated in group PHC (all P<0.05). Compared with group ALI, no significant differences were found in the W/D ratio, apoptotic index and the contents of TNF-α, IL-10 in group PNS(all P>0.05), while the expression of Nrf2 and HO-1 down-regulated in group PNS (all P<0.05). Compared with group PHC, the W/D ratio,apoptotic index and the contents of TNF-α,IL-10 increased, the expression of Nrf2 and HO-1 down-regulated in group PNS (all P<0.05). Conclusion: Nrf2/ARE signaling pathway is involved in the reduction of ALI by penehyclidine hydrochloride in neonate rats.
Assuntos
Lesão Pulmonar Aguda , Animais , Animais Recém-Nascidos , Antioxidantes , Endotoxinas , Pulmão , Fator 2 Relacionado a NF-E2 , Quinuclidinas , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Fator de Necrose Tumoral alfaRESUMO
Objective: To investigate the effect of the single lumen endobronchial tube and the double lumen endobronchial tube on ventilation and lung injury in patients with esophageal cancer undergoing combined thoracoscopic and laparoscopic esophagectomy. Methods: Sixty patients with esophageal cancer undergoing combined thoracoscopic and laparoscopic esophagectomy were divided into single lumen endobronchial tube group (D group, n=30) and double lumen endobronchial tube group (S, n=30) according to the random number table. Blood samples were harvested at the moment of tracheal intubation (T(0)), after artificial pneumothorax (one lung ventilation) 30 min (T(1)), after artificial pneumothorax (one lung ventilation) 90 min (T(2)), artificial pneumothorax over (double lung ventilation) 30 min (T(3)) and after extubation 30 min (T(4)) for arterial blood gas analysis. Heart rate (HR), mean arterial pressure (MAP), pulse oxygen saturation (SpO(2)), oxygen tension (PaO(2)), carbon dioxide partial pressure (PaCO(2)) and airway pressure (PAW) were recorded at T(0)-T(4). The incidences of pneumonia of two groups were record at 3 days after operation. Results: There were no obvious differences in HR, MAP, SpO(2), PaO(2), PaCO(2) between two groups at T(0)-T(4) (P>0.05). Compared with T(0), the levels of HR and PaO(2) were increased remarkably at T(1)-T(3) (P<0.05), the levels of PaCO(2) were increased remarkably at T(1)-T(4) (P<0.01), and the levels of Paw were increased remarkably at T(1)-T(3) (P<0.01). Compared with S group, the levels of Paw were decreased remarkably at T(1)-T(2) (29.5±3.7 vs 21.3±2.1, P=0.001; 30.7±4.8 vs 20.3±2.3, P=0.001). There were no obvious differences in the levels of TNF-α, IL-6, IL-8 in Bronchoalveolar Lavage Fluid (BALF) between two groups at T(0) (P>0.05). Compared with T(0), the levels of TNF-α, IL-6, IL-8 in BALF were increased remarkably at T(3), T(5) (P<0.05). Compared with S group, the levels of TNF-α, IL-6, IL-8 in D group in BALF were decreased remarkably at T(3), T(5) (P<0.05). Compared with S group, the incidence of pneumonia in D group were decreased remarkably at 3 days after operation (4(13.3%) vs 11(36.7%), P=0.017). Conclusion: The ventilation effect of the single lumen endobronchial tube on lung injury for patients with esophageal cancer undergoing combined thoracoscopic and laparoscopic esophagectomy is the same as that of the double lumen endobronchial tube, however the single lumen endobronchial tube has less injury on the lung.
Assuntos
Neoplasias Esofágicas , Lesão Pulmonar , Esofagectomia , Humanos , Laparoscopia , PulmãoRESUMO
Magnetic fractions (MFs) in industrially derived contaminated soils were extracted with a magnetic separation procedure. Total, soluble, and bioaccessible Cr, Cu, Pb and Zn in the MFs and non-magnetic fractions (NMFs) were analyzed using aqua regia and extraction tests, such as deionized water, toxicity characteristic leaching procedure (TCLP), and gastric juice simulation (GJST) test. Compared with the non-magnetic fractions, soil MFs were enriched with Fe, Mn, Pb, Cd, Cr, Cu, and Ni. Extraction tests indicated that soil MFs contained higher water, TCLP, and GJST-extractable Cr, Cu, Pb, and Zn concentrations than the soil NMFs. The TCLP-extractable Pb concentration in the MFs exceeded the USEPA hazardous waste criteria, suggesting that soil MFs have a potentially environmental pollution risk. Solubility of trace metals was variable in the different extraction tests, which has the order of GJST > TCLP > water. TCLP test showed Cu and Zn were more mobile than Cr and Pb while bioaccessibility of trace metal defined by GJST test showed the order of Cu ≈ Cr ≈ Zn > Pb. These findings suggested that the MFs in the industrially derived contaminated soils had higher possibility of polluting water bodies, and careful environmental impact assessment was necessary.
Assuntos
Metais/análise , Poluentes do Solo/análise , Oligoelementos/análise , Animais , China , Suco Gástrico/metabolismo , Humanos , Imãs/química , Metais/química , Metais/toxicidade , Microscopia Eletrônica de Varredura , Poluentes do Solo/química , Poluentes do Solo/toxicidade , Solubilidade , Espectrometria por Raios X , Oligoelementos/química , Oligoelementos/toxicidadeRESUMO
This work studied the effectiveness of fly ash in removing phosphate from aqueous solution and its related removal mechanism. The adsorption and precipitation of phosphate by fly ash were investigated separately in order to evaluate their role in the removal of phosphate. Results showed that the removal of phosphate by fly ash was rapid. The removal percentage of phosphate in the first 5min reached 68-96% of the maximum removal of phosphate by fly ash. The removal processes of phosphate by fly ash included a fast and large removal representing precipitation, then a slower and longer removal due to adsorption. The adsorption of phosphate on fly ash could be described well by Freundlich isotherm equation. The pH and Ca2+ concentration of fly ash suspension were decreased with the addition of phosphate, which suggests that calcium phosphate precipitation is a major mechanism of the phosphate removal. Comparison of the relative contribution of the adsorption and precipitation to the total removal of phosphate by fly ash showed that the adsorption accounted for 30-34% of the total removal of phosphate, depending on the content of CaO in fly ash. XRD patterns of the fly ash before and after phosphate adsorption revealed that phosphate salt (CaHPO4 x 2H2O) was formed in the adsorption process. Therefore, the removal of phosphate by fly ash can be attributed to the formation of phosphate precipitation as a brushite and the adsorption on hydroxylated oxides. The results suggested that the use of fly ash could be a promising solution to the removal of phosphate in the wastewater treatment and pollution control.
Assuntos
Carbono/química , Material Particulado/química , Fosfatos/química , Fosfatos/isolamento & purificação , Adsorção , Cinza de Carvão , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Soluções , Difração de Raios XRESUMO
The concentration of intracellular Ca(2+) ([Ca(2+)](i)) influences neuronal properties ranging from excitability to neurotransmitter release. Persistent inflammation is associated with changes in the properties of primary afferent neurons ranging from excitability to transmitter release. The purpose of the present study was to determine whether previously described inflammation-induced changes in excitability and transmitter release are associated with changes in the regulation of [Ca(2+)](i). Acutely dissociated dorsal root ganglion (DRG) neurons harvested from adult rats 3 days following a hind-paw injection of complete Freund's adjuvant (CFA) or naïve controls, were stimulated with 30 mM K(+) (High K(+)). High K(+) evoked changes in [Ca(2+)](i) were assessed with fura-2 ratiometric microfluorimetry. Subpopulations of DRG neurons were defined by cell body diameter, isolectin B4 (IB4) binding, capsaicin (CAP) sensitivity and target of innervation (1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbo-cyanine perchlorate labeling). Inflammation was associated with significant increases in resting [Ca(2+)](i) and increases in the magnitude and decreases in the decay, of the evoked increase in [Ca(2+)](i). The changes in evoked transients were larger in neurons innervating the site of inflammation. Furthermore, there were differences among subpopulations of DRG neurons with respect to changes in magnitude and/or decay of the evoked transient such that the increase in magnitude was larger in small- and medium-diameter neurons than in large diameter neurons while the decrease in the decay was greater in CAP responsive, IB4 positive, small- and medium-diameter neurons than in CAP unresponsive, IB4 negative and/or large-diameter neurons. These changes in the regulation of [Ca(2+)](i) were not due to inflammation-induced changes in passive or active electrophysiological properties. Importantly, an inflammation-induced increase in evoked Ca(2+) transients in putative nociceptive afferents may contribute to the pain and hyperalgesia associated with persistent inflammation via facilitation of transmitter release from these afferents.
Assuntos
Sinalização do Cálcio , Gânglios Espinais/metabolismo , Inflamação/metabolismo , Neurônios Aferentes/metabolismo , Nociceptores/metabolismo , Dor/metabolismo , Potenciais de Ação/efeitos dos fármacos , Animais , Cálcio/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Capsaicina/farmacologia , Tamanho Celular , Células Cultivadas , Fura-2 , Gânglios Espinais/efeitos dos fármacos , Inflamação/induzido quimicamente , Masculino , Neurônios Aferentes/efeitos dos fármacos , Neurotransmissores/metabolismo , Nociceptores/efeitos dos fármacos , Dor/induzido quimicamente , Lectinas de Plantas , Potássio/metabolismo , Potássio/farmacologia , Ratos , Ratos Sprague-Dawley , Transmissão Sináptica/efeitos dos fármacosRESUMO
The removal of phenanthrene and iodine from aqueous solutions in single and binary systems by inactivated soil indigenous bacterial biomass (SIBB), as well as affecting factors, were evaluated. Sorption kinetic and isotherm studies were carried out to investigate the synergistic effects of phenanthrene and iodine. Optimal parameters for the biosorption process included a solution pH of 6.0 and biosorbent dosage of 0.75 g L-1. The ionic strength significantly decreased the biosorption of both phenanthrene and iodine in single conditions, while no obvious influences were found in the binary conditions. A pseudo-second-order model was well fitted to the kinetic biosorption data for both phenanthrene and iodine. The results showed that the presence of co-solute accelerated the biosorption processes and the pseudo-second-order biosorption rates (k 2) for phenanthrene and iodine increased from 0.005441 to 0.009825 g mg-1 min-1 and from 0.000114 to 0.000223 g mg-1 min-1, respectively. The SIBB showed strong affinity with both phenanthrene and iodine, with a partition coefficient K d (Linear model) of 6892.4 L kg-1 for phenanthrene and affinity parameter K L (Langmuir model) of 232 500 L kg-1 for iodine. The presence of co-solute illustrated a synergistic effect on the biosorption of phenanthrene and iodine due to intermolecular forces between phenanthrene and iodine, enhancing the K d of 34.7% for phenanthrene and K L of 107.0% for iodine, respectively. The results suggested that SIBB was an effective material for the simultaneous biosorption of phenanthrene and iodine from aqueous solutions.
RESUMO
Taste receptor cells are primary sensory receptors utilized by the nervous system to detect the presence of gustatory stimuli in the oral cavity. These cells are particularly heterogeneous and may be divided into various subtypes based on morphological, histochemical, or physiological criteria. One example is the heterogeneous expression of neuropeptides, such as cholecystokinin and vasoactive intestinal polypeptide. These peptides are hypothesized to participate in the transduction processes. To pursue examination of this hypothesis, this study explored the relationship of peptide expression with two important and mostly non-overlapping transductive elements--the taste-specific G protein gustducin, involved in bitter and sweet transduction cascades, and the seven transmembrane taste receptor T1R2, hypothesized to respond to sweet compounds. Double labeling experiments were performed on taste buds of the posterior rat tongue combining immunocytochemistry for peptide expression and in situ hybridization experiments for either gustducin or T1R2 expression. Additionally, vasoactive intestinal peptide (VIP)-expression in posterior taste receptor cells was confirmed using the technique of RT-PCR. More than half (56%) of the CCK-expressing taste receptor cells co-expressed alpha-gustducin mRNA whereas far fewer (15%) co-expressed T1R2 mRNA. A majority of VIP-expressing taste receptor cells co-expressed alpha-gustducin mRNA (60%) whereas only 19% of these cells co-expressed T1R2 mRNA. More remarkable was the observation that these two peptides displayed almost identical expression patterns with these signal transduction molecules, suggesting that peptides are not randomly expressed with relation to signal transduction molecules. This observation supports the hypothesis that peptides may play roles in transduction. Further physiological exploration will be required to elucidate the nature of these roles.
Assuntos
Colecistocinina/metabolismo , Neurônios/metabolismo , Papilas Gustativas/citologia , Transducina/metabolismo , Peptídeo Intestinal Vasoativo/metabolismo , Animais , Contagem de Células , Colecistocinina/genética , Regulação da Expressão Gênica/fisiologia , Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Masculino , Neurônios/classificação , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodosRESUMO
Poly(vinylidene fluoride) (PVDF) based polymers are attractive for applications for artificial muscles, high energy density storage devices etc. Recently these polymers have been found great potential for being used as actuators for refreshable full-page Braille displays for visually impaired people in terms of light weight, miniaturized size, and larger displacement, compared with currently used lead zirconate titanate ceramic actuators. The applied voltages of published polymer actuators, however, cannot be reduced to meet the requirements of using city power. Here, we report the polymer actuator generating quite large displacement and blocking force at a voltage close to the city power. Our embodiments also show good self-healing performance and disuse of lead-containing material, which makes the Braille device safer, more reliable and more environment-friendly.
Assuntos
Algoritmos , Modelos TeóricosRESUMO
A mathematical model of soluble microbial products (SMPs) formation-degradation was established based on the activated sludge model no. 1 and was applied to the membrane bioreactor process with high concentration of activated sludge under intermittent aerobic operational condition. The simulation results were in good agreement with the experimental data which indicated that the coefficients used in the model could successfully describe the treatment performance. The most advantage of this modified model over the conventional one was that the significant importance of SMP existence was demonstrated and the model provided an reasonable comprehension for SMP concept. The present study demonstrated that SMPs contributed most to the organic matter in the effluent, and the results coincided well with the observations of many other researchers.
Assuntos
Biodegradação Ambiental , Reatores Biológicos , Simulação por Computador , Modelos Teóricos , Purificação da Água/métodos , Cinética , Membranas Artificiais , Poluentes Químicos da ÁguaRESUMO
Using the model of adriamycin-induced nephrotic syndrome in rats, we studied the relationship between urine electrolyte excretion rates and proteinuria and determined the activity of Na(+)-K(+)-ATPase in the renal tissue of nephrotic rats. No relationship was found between the increased sodium reabsorption and proteinuria. But the impaired salt excretion was inversely related to the increase of Na(+)-K(+)-ATPase activity in the renal inner medulla. It is proposed that direct effect of adriamycin on renal tubule cells is the primary events, that the increased Na(+)-ATPase activity on basolateral membrane of renal tubule cells be an intrarenal factor which mediates the action of retention of salt by the kidney and that inner medullary collecting ducts might be one of the sites of the sodium retention in nephrotic rats.
Assuntos
Síndrome Nefrótica/enzimologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Sódio/urina , Albuminúria/enzimologia , Animais , Doxorrubicina , Masculino , Síndrome Nefrótica/induzido quimicamente , Síndrome Nefrótica/urina , Ratos , Ratos Sprague-DawleyRESUMO
The existence of soluble microbial products (SMP) produced by microbial cultures involved in biological wastewater treatment process has been widely investigated. This paper aims to establish an available mathematical model by incorporating the SMP concept into the Activated Sludge Model (ASM) No. 3. Prediction of sewage treatment performance in membrane bioreactor process under intermittent aerobic condition by model simulation was presented, and the results provided a more comprehensive image for this process. It was found that SMP could not be ignored and it contributed about 15% of total COD in the reactor under HRT = 12 hr and SRT = 10 days condition. The model also provided reasonable simulation results for nitrogen, biomass concentration, and other treatment behaviors. Furthermore, the treatment performance can be predicted under various operating conditions by this proposed model.
Assuntos
Reatores Biológicos , Modelos Teóricos , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Previsões , Membranas Artificiais , SolubilidadeRESUMO
The inhibitory effects of dopamine (DA) applied spinally on the wide dynamic range (WDR) neurons of dorsal horn in rats were studied with extracellular recording technique. 54 WDR units were tested from 43 rats. With a dosage of DA from 0.26 x 10(-6) to 1.58 x 10(-6) mol/kg, the inhibitory effect of the neurotransmitter on the responses of dorsal horn neurons to noxious transcutaneous electrical stimulation exhibited a gradual increase. After DA (0.52 x 10(-6) mol/kg) administration, the inhibitory effect of DA began to appear in 5 min and reach to maximum in 15 min, whereupon the maximum level could be maintained for about 25 min. This effect of DA could be reversed completely by dopaminergic receptor antagonist, droperidol (0.66 x 10(-6) mol/kg) but not by 2.65 x 10(-6) mol/kg phentolamine or 1.37 x 10(-6) mol/kg naloxone. The results of the present investigation suggest that DA may be involved in the modulation of nociception at the spinal level as an independent neurotransmitter.
Assuntos
Dopamina/farmacologia , Nociceptores/fisiologia , Medula Espinal/fisiologia , Animais , Droperidol/farmacologia , Estimulação Elétrica , Potenciais Evocados/efeitos dos fármacos , Feminino , Masculino , Naloxona/farmacologia , Neurônios/fisiologia , Fentolamina/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Dopaminérgicos/fisiologiaRESUMO
A pilot-scale study of tertiary wastewater treatment of the JIZHUANGZI Municipal Wastewater Treatment Plant was carried out by preozonation, coagulation and direct filtration process with the aim of producing wastewater suitable for reuse. The proposed treatment scheme could produce a filtered water with lower turbidity, COD(Cr) and colour at lower ozone and coagulant dosages. Ozone was added into the mixing tank with coagulant simultaneously and postozonation was not cost effective. With the increase of ozone dosage, better COD(Cr) and colour removals were observed especially at the ozone dosage between 0.7-1.0 mg l(-1). Similarly, increasing ferric sulphate dosage resulted in better removals of turbidity, COD(Cr) and colour in the filtered water. In contrast, increasing polymer T-80 dosage seemed to improve colour removal rather than turbidity and COD(Cr). To achieve removal efficiency of 70% for turbidity, 45% for COD(Cr) and over 60% for colour, the optimum dosages of ozone, ferric sulphate and polymer T-80 should be 0.7-1.0 mg l(-1), 10.0-12.5 mg l(-1) and 0.7-1.0 mg l(-1), respectively.
Assuntos
Compostos Férricos/química , Filtração , Ozônio/química , Polímeros/química , Purificação da Água/instrumentação , Cor , Humanos , Projetos PilotoRESUMO
A laboratory composting was conducted to determine the effect of the continuously enforced aeration on the composting performance. The mixture of dog food, excess sludge, and woodchip was used as raw composting materials. The temperature changes in the decomposition process, and pH, weight loss, ash, and extract composition from the final product after 17 days composting were investigated. The results demonstrated that flow rate of enforced aeration indeed influenced the composting performance. Composting under 0.05-0.1 1 min(-1) condition seemed better than that under 0.2-0.41 min(-1) condition. Higher flow rate of air not only cooled the composting mixture significantly, further adversely affected temperature rise, but also evaporated moisture mostly. Thermophilic composting can occur under 0.05-0.11 min(-1) air flow rate condition, while composting in cases of 0.2-0.4 l min(-1) air flow rate mainly resulted in a mesophilic process. Microbial activity was considered to be significantly inhibited at 0.4 1 min(-1) air flow rate condition based on the analyses of total organic carbon and volatile fatty acids from water extraction of composting products.
Assuntos
Conservação dos Recursos Naturais , Alimentos , Eliminação de Resíduos/métodos , Movimentos do Ar , Ração Animal , Bactérias , Carbono/metabolismo , Ácidos Graxos/metabolismo , Concentração de Íons de Hidrogênio , Oxigênio , Temperatura , Volatilização , MadeiraRESUMO
This report studied on a hyperglycophilic yeast isolated from sweetened condensed milk in Shandong province. It can fermented glucose, sucrose and raffinose; and can assimilate glucose, sucrose and raffinose as its sole carbon source. According to the morphology, physiology and habitat, it was identified to be Candida lactiscondensi (Hammer) Meyer et Yarrow, one of the synonym is Torulopsis lactiscondensi (Hammer) Lodder et Kreger-van Rij (1952). Detailed description was given in this report.
Assuntos
Candida/classificação , Microbiologia de Alimentos , Leite/microbiologia , Animais , Candida/isolamento & purificação , Conservação de AlimentosRESUMO
Persistent inflammation is associated with a shift in spinal GABA(A) signaling from inhibition to excitation such that GABA(A)-receptor activation contributes to inflammatory hyperalgesia. We tested the hypothesis that the primary afferent is the site of the persistent inflammation-induced shift in GABA(A) signaling which is due to a Na(+)-K(+)-Cl(-)-co-transporter (NKCC1)-dependent depolarization of the GABA(A) current equilibrium potential (E(GABA)). Acutely dissociated retrogradely labeled cutaneous dorsal root ganglion (DRG) neurons from naïve and inflamed (3 days after a subcutaneous injection of complete Freund's adjuvant) adult male rats were studied with Ca(2+) imaging, western blot and gramicidin-perforated patch recording. GABA evoked a Ca(2+) transient in a subpopulation of small- to medium-diameter capsaicin-sensitive cutaneous neurons. Inflammation was associated with a significant increase in the magnitude of GABA-induced depolarization as well as the percentage of neurons in which GABA evoked a Ca(2+) transient. There was no detectable change in NKCC1 protein or phosphoprotein at the whole ganglia level. Furthermore, the increase in excitatory response was comparable in both HEPES- and HCO(3)(-)-buffered solutions, but was only associated with a depolarization of E(GABA) in HCO(3)(-)-based solution. In contrast, under both recording conditions, the excitatory response was associated with an increase in GABA(A) current density, a decrease in low threshold K(+) current density, and resting membrane potential depolarization. Our results suggest that increasing K(+) conductance in afferents innervating a site of persistent inflammation may have greater efficacy in the inhibition of inflammatory hyperalgesia than attempting to drive a hyperpolarizing shift in E(GABA).