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2.
Zhonghua Jie He He Hu Xi Za Zhi ; 45(1): 111-115, 2022 Jan 12.
Artigo em Chinês | MEDLINE | ID: mdl-35000316

RESUMO

Malignant pleural mesothelioma (MPM) is a kind of invasive malignant tumor originated from pleural tissue. The incidence of MPM is not high in the population, but the prognosis is very poor. The median survival time is only about 12 months. Pemetrexed combined with platinum is the first-line chemotherapy regimen recommended by the current guidelines. The use of bevacizumab will further prolong the survival of chemotherapy. Once resistance happened, no anti-tumor treatment has been confirmed to achieve survival benefits. Therefore, there is no recommended standard second-line MPM regimen in international and domestic guidelines, including National Comprehensive Cancer Network (NCCN) guidelines. Vinorelbine, gemcitabine and other monotherapy regimens are commonly used in clinical practice, but the median progression free survival (PFS) is only about 3 months. Immune checkpoint inhibitors (ICIS) have been proved to have a significant inhibitory effect on tumor growth in a variety of malignant tumors, and their efficacy is related to the expression of programmed death-ligand 1(PD-L1). In unresectable MPM, programmed death 1 (PD-1)/PD-L1 inhibitors have been used in a series of clinical studies in the first-line, second-line and above treatment. Some of the results have been cited and recommended by international guidelines, but the overall efficacy improvement is still limited. This review summarizes the latest clinical studies and researches in the field of MPM treatment and predicts the directions and prospect of improving the therapeutic effect in the future.


Assuntos
Neoplasias Pulmonares , Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Mesotelioma/tratamento farmacológico , Pemetrexede/uso terapêutico , Pleura , Neoplasias Pleurais/tratamento farmacológico , Prognóstico
3.
Zhonghua Gan Zang Bing Za Zhi ; 28(9): 737-741, 2020 Sep 20.
Artigo em Chinês | MEDLINE | ID: mdl-33053972

RESUMO

Objective: To investigate and analyze the current situation, screening, clinical characteristics, prevention and treatment of bleeding esophageal varices in cirrhotic patients with portal hypertension in Tibet region. Methods: Clinical data of cirrhotic patients with portal hypertension through March 2017 to February 2020 from Tibet region were collected and analyzed retrospectively. Results: 511 cases with liver cirrhosis were included in the study, of which 185 cases (36.20%) had compensated cirrhosis and 326 cases (63.80%) had decompensated cirrhosis. Further analysis of the etiological data of liver cirrhosis showed that 306 cases (59.88%) were of chronic hepatitis B, 113 cases (22.11%) of alcoholic liver disease, and 68 cases (13.31%) of chronic hepatitis B combined with alcoholic liver disease. Among patients with compensated liver cirrhosis, 48 cases (25.95%) underwent endoscopic examination of which 33 diagnosed as high-risk variceal bleeding. However, none of these 33 cases had received non-selective ß-blocker therapy, and only four patients had received endoscopic variceal banding therapy. Among patients with decompensated liver cirrhosis, 83 cases (25.46%) had a history of upper gastrointestinal bleeding, 297 cases (91.10%) had ascites, 23 cases (7.05%) had hepatic encephalopathy, and 3 cases (0.92%) had hepatorenal syndrome. Among the patients with a history of upper gastrointestinal bleeding, 42 cases (50.60%) had received secondary preventive treatment for bleeding esophageal varices, including 39 cases of endoscopic treatment, 1 case of endoscopic combined drug treatment, 3 cases of interventional treatment, and 2 cases of surgical treatment. Conclusion: Chronic hepatitis B and alcoholic liver diseases are the main causes of liver cirrhosis in Tibet region. Moreover, this region lacks screening, prevention and treatment for bleeding esophageal varices in cirrhotic patients with portal hypertension. Therefore, it is necessary to increase the screening of high-risk groups to prevent and improve the first-time bleeding, and promote multidisciplinary team to prevent and treat re-bleeding.


Assuntos
Varizes Esofágicas e Gástricas , Hipertensão Portal , Varizes Esofágicas e Gástricas/epidemiologia , Varizes Esofágicas e Gástricas/etiologia , Varizes Esofágicas e Gástricas/prevenção & controle , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/prevenção & controle , Humanos , Hipertensão Portal/complicações , Cirrose Hepática/complicações , Estudos Retrospectivos , Tibet
4.
Zhonghua Zhong Liu Za Zhi ; 42(9): 771-776, 2020 Sep 23.
Artigo em Chinês | MEDLINE | ID: mdl-32988161

RESUMO

Objective: Recently, increasing number of lung cancer patients benefit from immune-checkpoint inhibitors (ICIs). However, the data of Chinese small cell lung cancer (SCLC) patients is limited. This study aims to analyze the response and survival data of ICIs treatment in SCLC and to explore the predictive biomarkers. Methods: Forty-seven SCLC patients who received ICIs treatment from Peking University Cancer Hospital from May 2017 to September 2019 was recruited. Clinical characteristics including sex, age, smoking status, ICIs strategy, PD-L1 expression and therapeutic efficacy were collected to explore the clinical predictive biomarkers for SCLC ICIs treatment. Results: Among the 47 patients, 18 (38.3%) cases were partial repose (PR), 11 (23.4%) were stable disease (SD), 18 (38.3%) were progressive disease (PD), and the objective response rate (ORR) was 38.3%, disease control rate (DCR) was 61.7%, the median progression-free survival (PFS) was 5.3 months. ICIs monotherapy accounts for 27.7%, the ORR was 15.4%, DCR was 53.8%, median PFS was 2.7 months. Combined therapy accounts for 72.3%, the ORR was 47.1%, DCR was 64.7%, median PFS was 5.4 months. Fourteen (29.8%) patients received ICIs as the first line treatment, their ORR was 85.7%, DCR was 100%, median PFS was 9.1 month. The ORR was not related to the age, sex, body mass index (BMI), smoking status and programmed death-ligand 1 (PD-L1) expression (P>0.05). The ORRs were higher in patients underwent PD-L1 monotherapy (P=0.001), combined therapy (P=0.002) and received ICIs as the first line treatment (P<0.001). Log-rank analysis indicated that the PFS of female patients were 12.0 months, significantly longer than 4.4 months of male patients in ICIs treatment (P=0.038). Patients who received PD-L1 monotherapy, combined treatment, or ICIs as the first line treatment had longer PFS than their counterparts, though no statistical significant was observed (P>0.05). Cox multivariate analysis showed that, the gender was not an independent predictor for PFS in ICIs treatment (HR=3.777, 95%CI=0.974~30.891, P=0.054). Conclusions: Immunotherapy is an effective treatment strategy for SCLC. Patients who receive combined ICIs treatment, first line ICIs treatment and PD-L1 treatment may get greater benefits. PD-L1 expression cannot predict the response and PFS in SCLC ICIs treatment.


Assuntos
Antineoplásicos Imunológicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Antineoplásicos Imunológicos/uso terapêutico , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Feminino , Humanos , Imunoterapia , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico
5.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(6): 641-644, 2019 Nov 05.
Artigo em Chinês | MEDLINE | ID: mdl-32064810

RESUMO

OBJECTIVE: To investigate the status of human intestinal parasitic diseases in Nanping City from 2014 to 2018, so as to provide reference for the development of the effective control measures. METHODS: Administrative villages were selected using the two-stage cluster sampling in Nanping City from 2014 to 2018, and surveillance of human intestinal parasitic diseases was performed in 5 administrative villages in each county (district) of Nanping City. Intestinal parasitic infections were detected using a modified Kato-Katz thick smear method (two smears for a single stool sample) in villagers, and the hookworm species was differentiated. In addition, the eggs of Enterobius vermicularis were detected using the adhesive tape method in children aged 3 to 6 years. RESULTS: A total of 6 317 villagers were detected in Nanping City from 2014 to 2018, and the overall prevalence of human intestinal parasitic infections was 2.15%. There was year- (χ2 = 10.53, P < 0.05) and gender-specific prevalence of human intestinal parasitic infections in Nanping City during the study period (χ2 = 17.00, P < 0.01). The prevalence of human intestinal parasitic infections increased with age, and there was age-specific prevalence of human intestinal parasitic infections in Nanping City (χ2 = 102.62, P < 0.01). A total of 945 children at ages of 3 to 6 years were detected, and the prevalence of E. vermicularis infection was 3.28%. CONCLUSIONS: The prevalence of human intestinal parasitic infections is at a low level in Nanping City from 2014 to 2018, and the infection mainly occurs in villagers of advanced age and low education levels. Further comprehensive measures are required to control intestinal parasitic infections in key populations.


Assuntos
Enteropatias Parasitárias , Animais , Criança , Pré-Escolar , China/epidemiologia , Fezes/parasitologia , Humanos , Enteropatias Parasitárias/epidemiologia , Prevalência
6.
Eur J Gynaecol Oncol ; 38(3): 449-452, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29693889

RESUMO

PURPOSE: Long non-coding RNAs (lncRNAs) have been proved to play important roles in the tumorigenesis and development of human epithelial ovarian cancer (EOC). The aim of the present study was to investigate the expression and clinical value of BRAF-activated non-coding RINA (BANCR) in EOC patients. MATERIALS AND METHODS: BANCR expression was detected in 84 EOC and 36 normal ovarian epithelial tissue samples. Association between BANCR levels and clinicopathological factors and patient prognosis was also analyzed. RESULTS: BANCR expression was increased in EOC compared with normal ovarian epithelial tissues. Moreover, high expression of BANCR was closely correlated with advanced FIGO stage, higher serum, CAI125 expression level, and lymph node metastasis. Multivariate regression analysis identified BANCR overexpression as an independent unfavorable prognostic factor in EOC patients. CONCLUSIONS: These findings suggested that BANCR may act as a tumor promoter in EOC and would be a novel diagnostic and prognostic marker for this disease.


Assuntos
Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , RNA Longo não Codificante/análise , Adulto , Idoso , Carcinoma Epitelial do Ovário , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/mortalidade , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Prognóstico
8.
Curr Mol Med ; 16(8): 702-709, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27686798

RESUMO

Pancreatic cancer remains a worldwide issue and burden that is hard to resolve given its low resection rate and chemo-resistance. Early diagnosis and early treatment are critical for conquering pancreatic cancer. Therefore, new biomarkers for diagnosis and prognosis are urgently needed. Previously, researchers mainly focused on protein-coding genetic and epigenetic changes in many types of cancers, and regarded the noncoding part as waste. Recently, however, long non-coding RNA (lncRNA) has emerged as a major participant in carcinogenesis, as it regulates cell proliferation, migration, invasion, metastasis, chemo-resistance, etc. The underlying mechanisms are summarized as signaling, decoy, guide and scaffold, yet the specific regulation networks remain to be uncovered. Several studies have revealed that some lncRNAs are dysregulated in pancreatic cancer, participating in biological functions. In this review, we will briefly outline the functional lncRNAs in pancreatic cancer, decipher possible mechanisms of lncRNAs, and further explore their significance in pancreatic cancer.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias Pancreáticas/genética , RNA Longo não Codificante/genética , Biomarcadores Tumorais , Carcinogênese/genética , Humanos , Neoplasias Pancreáticas/metabolismo
11.
HLA ; 87(2): 115-6, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26812171

RESUMO

Five Mafa-DPB1, two Mafa-DQB1 and three Mafa-DRB novel alleles are identified in Vietnamese cynomolgus macaques.


Assuntos
Alelos , Antígenos de Histocompatibilidade Classe II/genética , Animais , Macaca fascicularis , Vietnã
12.
Tissue Antigens ; 80(6): 494-501, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23137320

RESUMO

Cynomolgus macaques (Macaca fascicularis, Mafa) have emerged as an important animal model for infectious disease and transplantation research. Extensive characterization of their major histocompatibility complex (MHC) polymorphism regions therefore becomes urgently required. In this study, we identified 41 MHC class I A nucleotide sequences in 34 unrelated cynomolgus macaques of Vietnamese origin farmed in Southern China, including eight novel Mafa-A sequences. We found two sequences with perfect identity and six sequences with close similarity to previously defined MHC class I alleles from other populations, especially from Indonesian-origin macaques. We also found three Vietnamese-origin cynomolgus macaque MHC class I sequences for which the predicted protein sequences identical throughout their B and F binding pockets to Mamu-A1*001:01 and Mamu-A3*13:03, respectively. This is important because Mamu-A1*001:01 and Mamu-A3*13:03 are associated with longer survival and lower set-point viral load in simian immunodeficiency virus (SIV)-infected rhesus monkeys. These findings have implications for the evolutionary history of Vietnamese-origin cynomolgus macaque as well as for the use of this model in SIV/SHIV (a virus combining parts of the HIV and SIV genomes) research.


Assuntos
Genes MHC Classe I , Macaca fascicularis/genética , Macaca fascicularis/imunologia , Alelos , Sequência de Aminoácidos , Animais , Sequência de Bases , Primers do DNA/genética , Evolução Molecular , Genética Populacional , Antígenos de Histocompatibilidade Classe I/genética , Macaca/genética , Macaca/imunologia , Modelos Animais , Dados de Sequência Molecular , Filogenia , Homologia de Sequência de Aminoácidos , Vírus da Imunodeficiência Símia/imunologia , Vírus da Imunodeficiência Símia/patogenicidade , Especificidade da Espécie , Vietnã
14.
15.
Mol Pain ; 1: 23, 2005 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-16111486

RESUMO

The anterior cingulate cortex (ACC) plays an important role in higher brain functions including learning, memory, and persistent pain. Long-term potentiation of excitatory synaptic transmission has been observed in the ACC after digit amputation, which might contribute to plastic changes associated with the phantom pain. Here we report a long-lasting membrane potential depolarization in ACC neurons of adult rats after digit amputation in vivo. Shortly after digit amputation of the hind paw, the membrane potential of intracellularly recorded ACC neurons quickly depolarized from approximately -70 mV to approximately -15 mV and then slowly repolarized. The duration of this amputation-induced depolarization was about 40 min. Intracellular staining revealed that these neurons were pyramidal neurons in the ACC. The depolarization is activity-dependent, since peripheral application of lidocaine significantly reduced it. Furthermore, the depolarization was significantly reduced by a NMDA receptor antagonist MK-801. Our results provide direct in vivo electrophysiological evidence that ACC pyramidal cells undergo rapid and prolonged depolarization after digit amputation, and the amputation-induced depolarization in ACC neurons might be associated with the synaptic mechanisms for phantom pain.

16.
J Neurophysiol ; 88(6): 2928-41, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12466419

RESUMO

Modulatory influences on spinal mechanical transmission from the rostral medial medulla (RMM) were studied. Noxious stimulation, produced by von Frey-like monofilaments, and non-noxious stimulation, produced by a soft brush, was applied to the glabrous skin of the hind foot. At 28 sites in RMM, electrical stimulation facilitated responses to noxious mechanical stimulation at low intensities (5-25 microA) and inhibited responses of the same neurons at greater intensities (50-100 microA) of stimulation. At 24 and 9 other sites in RMM, stimulation at all intensities only inhibited or only facilitated, respectively, responses to noxious mechanical stimulation of the hind foot. Stimulus-response functions to mechanical stimulation were shifted leftward by low intensities and decreased by high intensities of stimulation. Inhibitory influences were found to descend in the dorsolateral funiculi; facilitatory effects were contained in the ventral spinal cord. Descending modulation of non-noxious brush stimulation revealed biphasic facilitatory-inhibitory effects (9 sites in RMM), only inhibitory effects (14 sites) and only facilitatory effects (8 sites). The effects of electrical stimulation were replicated by intra-RMM administration of glutamate; a low concentration (0.25 nmol) facilitated and a greater concentration (2.5 nmol) inhibited spinal mechanical transmission, providing evidence that cells in RMM are sufficient to engage descending influences. Descending modulatory effects were specific for the site of stimulation, not for the spinal neuron, because modulation of the same neuron was different from different sites in RMM. These results show that spinal mechanical transmission, both noxious and non-noxious, is subject to descending influences, including facilitatory influences that may contribute to exaggerated responses to peripheral stimuli in some chronic pain states.


Assuntos
Bulbo/fisiologia , Nociceptores/fisiologia , Medula Espinal/fisiologia , Transmissão Sináptica , Animais , Estimulação Elétrica , Ácido Glutâmico/farmacologia , Humanos , Masculino , Bulbo/efeitos dos fármacos , Microinjeções , Inibição Neural , Estimulação Física , Ratos , Ratos Sprague-Dawley , Tempo de Reação
17.
J Neurophysiol ; 87(5): 2225-36, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11976363

RESUMO

Descending inhibitory and facilitatory influences from the rostroventral medulla (RVM) on responses of lumbosacral spinal neurons to noxious colorectal distension (CRD, 80 mmHg, 20 s) were studied. At 25 sites in the RVM, electrical stimulation produced biphasic effects, facilitating responses of spinal neurons to CRD at lesser intensities of stimulation (5-25 microA) and inhibiting responses of the same neurons at greater intensities of stimulation (50-100 microA). At 38 other sites in the RVM, electrical stimulation produced only intensity-dependent inhibition of neuron responses to CRD. At another 13 sites in the RVM, electrical stimulation (5-100 microA) produced only facilitatory effects on responses to CRD. Descending modulatory effects were selective for distension-evoked activity; spontaneous activities of the same spinal neurons were not significantly affected by electrical stimulation that either facilitated or inhibited neuron responses to CRD. Neuron responses to graded CRD (20-100 mmHg) were positively accelerating functions that were shifted leftward or rightward, respectively, by lesser, facilitatory intensities or greater, inhibitory intensities of RVM stimulation. L-glutamate microinjection into the RVM replicated the effects of electrical stimulation, producing similar biphasic modulatory effects as produced by electrical stimulation. Microinjection of glutamate into the RVM at a low dose (5 nmoles) facilitated responses of spinal neurons to CRD and inhibited responses of the same neurons at a greater dose (50 nmoles). In some experiments, microinjection of lidocaine (0.5 microl of 4% solution) or the neurotoxin ibotenic acid (0.5 microl, 10 microg) into the RVM produced reversible or long-lasting, respectively, decreases in spontaneous activity and responses of spinal neurons to CRD. These results reveal that spinal visceral nociceptive transmission is subject to a tonic descending excitatory influence from the RVM and that descending modulatory effects from the RVM on visceral nociceptive transmission are qualitatively similar to modulation of cutaneous nociceptive transmission.


Assuntos
Bulbo/citologia , Bulbo/fisiologia , Nociceptores/fisiologia , Medula Espinal/citologia , Medula Espinal/fisiologia , Animais , Cateterismo , Colo/inervação , Vias Eferentes/efeitos dos fármacos , Vias Eferentes/fisiologia , Estimulação Elétrica , Ácido Glutâmico/farmacologia , Masculino , Inibição Neural/efeitos dos fármacos , Inibição Neural/fisiologia , Nociceptores/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Reto/inervação , Estimulação Química , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
18.
J Physiol ; 540(Pt 2): 593-606, 2002 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11956346

RESUMO

As a neurohormone and as a neurotransmitter, oxytocin has been implicated in the stress response. Descending oxytocin-containing fibres project to the dorsal horn of the spinal cord, an area important for processing nociceptive inputs. Here we tested the hypothesis that oxytocin plays a role in stress-induced analgesia and modulates spinal sensory transmission. Mice lacking oxytocin exhibited significantly reduced stress-induced antinociception following both cold-swim (10 degrees C, 3 min) and restraint stress (30 min). In contrast, the mice exhibited normal behavioural responses to thermal and mechanical noxious stimuli and morphine-induced antinociception. In wild-type mice, intrathecal injection of the oxytocin antagonist dOVT (200 microM in 5 microl) significantly attenuated antinociception induced by cold-swim. Immunocytochemical staining revealed that, in the mouse, oxytocin-containing neurones in the paraventricular nucleus of the hypothalamus are activated by stress. Furthermore, oxytocin-containing fibres were present in the dorsal horn of the spinal cord. To test whether descending oxytocin-containing fibres could alter nociceptive transmission, we performed intracellular recordings of dorsal horn neurones in spinal slices from adult mice. Bath application of oxytocin (1 and 10 microM) inhibited excitatory postsynaptic potentials (EPSPs) evoked by dorsal root stimulation. This effect was reversed by the oxytocin antagonist dOVT (1 microM). Whole-cell recordings of dorsal horn neurones in postnatal rat slices revealed that the effect of oxytocin could be blocked by the addition of GTP-gamma-S to the recording pipette, suggesting activation of postsynaptic oxytocin receptors. We conclude that oxytocin is important for both cold-swim and restraint stress-induced antinociception, acting by inhibiting glutamatergic spinal sensory transmission.


Assuntos
Analgesia/psicologia , Ocitocina/fisiologia , Estresse Psicológico/psicologia , Animais , Comportamento Animal/fisiologia , Western Blotting , Eletrofisiologia , Imuno-Histoquímica , Hibridização In Situ , Masculino , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Knockout , Neurônios Aferentes/fisiologia , Ocitocina/genética , Medição da Dor/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/fisiologia , Técnicas de Patch-Clamp , Células do Corno Posterior/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Medula Espinal/fisiologia , Natação/psicologia , Transmissão Sináptica/fisiologia
19.
Neuron ; 32(3): 477-88, 2001 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-11709158

RESUMO

In the spinal cord dorsal horn, excitatory sensory fibers terminate adjacent to interneuron terminals. Here, we show that kainate (KA) receptor activation triggered action potential-independent release of GABA and glycine from dorsal horn interneurons. This release was transient, because KA receptors desensitized, and it required Na+ entry and Ca2+ channel activation. KA modulated evoked inhibitory transmission in a dose-dependent, biphasic manner, with suppression being more prominent. In recordings from isolated neuron pairs, this suppression required GABA(B) receptor activation, suggesting that KA-triggered GABA release activated presynaptic GABA(B) autoreceptors. Finally, glutamate released from sensory fibers caused a KA and GABA(B) receptor-dependent suppression of inhibitory transmission in spinal slices. Thus, we show how presynaptic KA receptors are linked to changes in GABA/glycine release and highlight a novel role for these receptors in regulating sensory transmission.


Assuntos
Glicina/metabolismo , Células do Corno Posterior/metabolismo , Terminações Pré-Sinápticas/metabolismo , Receptores de Ácido Caínico/fisiologia , Ácido gama-Aminobutírico/metabolismo , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Agonistas de Aminoácidos Excitatórios/farmacologia , Ativação do Canal Iônico/efeitos dos fármacos , Ativação do Canal Iônico/fisiologia , Ácido Caínico/farmacologia , Masculino , Células do Corno Posterior/efeitos dos fármacos , Terminações Pré-Sinápticas/efeitos dos fármacos , Ratos , Células Receptoras Sensoriais/efeitos dos fármacos , Células Receptoras Sensoriais/metabolismo
20.
Brain Res Bull ; 55(4): 521-31, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11543953

RESUMO

Spinal nociceptive transmission is mediated by glutamate and neuropeptides such as substance P (SP) and neurokinin A (NKA). The neuropeptide-mediated excitatory postsynaptic potentials (EPSPs) had a slow onset and long duration. Here, we demonstrate SP- and NKA-mediated excitatory postsynaptic currents (EPSCs) in dorsal horn neurons of young rats using whole-cell patch-clamp recording techniques. After complete blockade of glutamate receptor-mediated currents, we observed a small residual EPSC. The residual EPSCs exhibited temporal summation in response to a train of stimulation (six pulses delivered at 10-50 Hz). High intensity stimulation (the same or greater than the stimulation threshold for nociceptive fibers in vivo) was required for evoking these summated EPSCs. Summated EPSCs were attenuated or abolished by capsaicin pretreatment, which depletes SP and NKA from presynaptic terminals; SP and NKA pretreatment; NK(1) or NK(2) receptor antagonists; and inhibition of postsynaptic G proteins. EPSCs were neither blocked by a metabotropic glutamate receptor antagonist nor a gamma-aminobutyric acid(B) receptor antagonist. The summated EPSCs were also sensitive to voltage-gated calcium channel antagonists or mu-opioid receptor activation by DAMGO. The present study provides electrophysiological evidence that suggests the possible contribution of SP and NKA to sensory synaptic transmission between primary afferent fibers and dorsal horn neurons.


Assuntos
Neurocinina A/farmacologia , Células do Corno Posterior/metabolismo , Substância P/farmacologia , Transmissão Sináptica/efeitos dos fármacos , 2-Amino-5-fosfonovalerato/metabolismo , 6-Ciano-7-nitroquinoxalina-2,3-diona/farmacologia , Fatores Etários , Analgésicos Opioides/farmacologia , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo P/metabolismo , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Antagonistas GABAérgicos/farmacologia , Guanosina Difosfato/análogos & derivados , Guanosina Difosfato/farmacologia , Técnicas In Vitro , Dor/metabolismo , Técnicas de Patch-Clamp , Ácidos Fosfínicos/farmacologia , Células do Corno Posterior/efeitos dos fármacos , Propanolaminas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de Glutamato/metabolismo , Receptores da Neurocinina-1/metabolismo , Receptores da Neurocinina-2/metabolismo , Tionucleotídeos/farmacologia , ômega-Conotoxina GVIA/farmacologia
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