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1.
Rhinology ; 62(1): 23-34, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37902657

RESUMO

BACKGROUND: Surgical treatment is playing an increasingly important role in the management of nasopharyngeal carcinoma (NPC). This consensus focuses on the indications for optimal surgery, and surgical methods in the whole process of treatment for NPC to provide a useful reference to assist these difficult clinical decisions. METHODOLOGY: A thorough review of available literature on NPC and surgery was conducted by the Association for the prevention and treatment of nasopharyngeal carcinoma in China, international exchange and promotion Association for medicine and healthcare, and the Committee on nasopharyngeal cancer of Guangdong provincial anticancer association. A set of questions and a preliminary draft guideline was circulated to a panel of 1096 experienced specialists on this disease for voting on controversial areas and comments. A refined second proposal, based on a summary of the initial voting and different opinions expressed, was recirculated to the experts in two authoritative medical science and technology academic groups in the prevention and treatment of NPC in China for review and reconsideration. RESULTS: The initial round of questions showed variations in clinical practice even among similar specialists, reflecting the lack of high-quality supporting data and resulting difficulties in formulating clinical decisions. Through exchange of comments and iterative revisions, recommendations with high-to-moderate agreement were formulated on general treatment strategies and details of surgery, including indications and surgical approaches. CONCLUSION: By standardizing the surgical indications and practice, we hope not only to improve the surgical outcomes, but also to highlight the key directions of future clinical research in the surgical management of NPC.


Assuntos
Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/cirurgia , Neoplasias Nasofaríngeas/cirurgia , Neoplasias Nasofaríngeas/patologia , Consenso , Medicina Baseada em Evidências/métodos , China
3.
Zhonghua Zhong Liu Za Zhi ; 42(3): 252-256, 2020 Mar 23.
Artigo em Chinês | MEDLINE | ID: mdl-32252206

RESUMO

Objective: To evaluate the performance of Hybribio human papillomavirus (HPV) typing test kit for high risk HPV-DNA typing detection in screening of cervical precancer lesions. Methods: A total of 9 914 women were recruited in Henan, Shanxi, and Guangdong provinces from June to July 2017. All women underwent HPV DNA test. The women who diagnosed as HPV positive and cytological examination ≥ atypical squamous cells of undetermined significance (ASCUS) or HPV negative and cytological examination≥low-grade squamous intraepithelial lesions (LSIL) underwent colposcopy biopsy and pathological examination. Using the pathological diagnosis as the gold standard, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and 95% confidence interval (CI) of high-risk HPV and HPV16/18 tests were calculated. Results: The mean age of 9 914 subjects was (45.0±9.3) years old. Among them, 1 302 subjects were detected as high risk HPV positive, including 211 of HPV16 positive and 64 of HPV18 positive. According to the pathological gold standard of cervical intraepithelial neoplasia grade 2 (CIN2) or worse, the sensitivity and specificity of high risk-HPV and HPV 16/18 for triaging ASCUS women were 90.6% (95%CI: 75.8%-96.8%) and 78.0% (95%CI: 74.5%-81.2%) as well as 56.3% (95%CI: 39.3%-71.8%) and 95.7% (95%CI: 93.8%-97.1%), respectively. The sensitivity and specificity of high risk-HPV and HPV 16/18 for cervical precancer lesions screening were 95.1% (95%CI: 88.1%-98.1%) and 87.6% (95%CI: 86.9%-88.2%) as well as 65.9% (95%CI: 55.1%-75.2%) and 97.8% (95%CI: 97.5%-98.1%), respectively. Conclusions: The Hybribio HPV test kit has a relative high sensitivity and specificity for cervical precancer lesions screening and ASCUS triaging. It is reliable for HPV DNA detection and cervical cancer screening.


Assuntos
Detecção Precoce de Câncer , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Teste de Papanicolaou , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/complicações , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Adulto , Biópsia , Colo do Útero/patologia , Colo do Útero/virologia , Colposcopia , DNA Viral/análise , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Papillomaviridae/classificação , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/virologia , Valor Preditivo dos Testes , Gravidez , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia
4.
Eur Rev Med Pharmacol Sci ; 23(10): 4313-4320, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31173304

RESUMO

OBJECTIVE: Exercise-based intervention promises to be more effective in a structured framework for individuals with autism spectrum disorders (ASD). The aim of this study was to observe changes in behavior of individuals with ASD by investigating their physical status after the structured exercise-based intervention. PATIENTS AND METHODS: The exercise intervention integrated an 8-week exercise program that included aerobic, resistive, and neuromuscular exercises. Body composition and the Autism Treatment Evaluation Checklist (ATEC) were evaluated to assess changes after the exercise-based intervention. RESULTS: After the exercise intervention, the fat mass of individuals with ASD were significantly reduced, and their behavior improved markedly. CONCLUSIONS: This pilot study demonstrated that individuals with ASD require long-term, structured exercise-based intervention, and that such exercise-based intervention is effective for improving their health.


Assuntos
Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/terapia , Terapia por Exercício/métodos , Adolescente , Transtorno do Espectro Autista/psicologia , Conscientização , Composição Corporal , Distribuição da Gordura Corporal , Criança , Comunicação , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Projetos Piloto , Treinamento Resistido , Comportamento Social , Resultado do Tratamento
5.
Eur Rev Med Pharmacol Sci ; 18(2): 160-4, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24488902

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is a clinicopathologic syndrome of which the main feature is diffuse macrovesicular hepatic steatosis caused by deposition of excessive free fatty acid and triglyceride in liver parenchyma. AIM: To observe the efficacy of Tiopronin in treatment of severe nonalcoholic fatty liver disease (NAFLD). PATIENTS AND METHODS: 30 patients with severe NAFLD were treated with Tiopronin for 3 months. 30 healthy people were selected as control. The body mass index (BMI) and plasma levels of endotoxin (ET), leptin, IL-6 and IL-8 were measured before and after treatment. RESULTS: The serum levels of ET, leptin, IL-6 and IL-8 in severe NAFLD group were significantly higher than those in control group (p < 0.05). After treatment with Tiopronin, these indexes were significantly lower than before (p < 0.05). CONCLUSIONS: The intestinal endotoxemia (IETM) occurs in patients with severe NAFLD. Leptin, IL-6 and IL-8 play important roles in pathogenesis of NAFLD. Tiopronin can reduce the levels of ET, leptin, IL-6 and IL-8 for treatment of NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Tiopronina/uso terapêutico , Adulto , Índice de Massa Corporal , Endotoxinas/sangue , Feminino , Humanos , Interleucina-6/sangue , Interleucina-8/sangue , Leptina/sangue , Masculino , Hepatopatia Gordurosa não Alcoólica/sangue , Triglicerídeos/sangue
6.
J Int Med Res ; 40(2): 556-64, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22613416

RESUMO

OBJECTIVE: T helper 17 (Th17) cells play important roles in adaptive immunity and are involved in several inflammatory and autoimmune diseases, but little is known about their role in tumour immunity. The current study investigated the involvement of Th17 cells in multiple myeloma. METHODS: Flow cytometry was used to investigate the frequencies of Th17 cells in peripheral blood mononuclear cells from 30 patients with multiple myeloma and from 14 healthy control subjects. The concentrations of Th17-associated cytokines (interleukin [IL]-6, IL-17, IL-1ß and IL-23) were measured by enzyme-linked immunosorbent assay. RESULTS: There was a significantly increased proportion of Th17 cells, and increased plasma concentrations of Th17-associated cytokines, in patients with multiple myeloma compared with healthy controls. There was a significant relationship between the proportion of Th17 cells and clinical tumour stage, serum lactate dehydrogenase concentration and serum creatinine concentration. CONCLUSIONS: Th17 cells might be important therapeutic targets in multiple myeloma and could facilitate a better outcome for tumour immunotherapy.


Assuntos
Mieloma Múltiplo/imunologia , Células Th17/imunologia , Idoso , Antineoplásicos/uso terapêutico , Contagem de Linfócito CD4 , Creatinina/sangue , Feminino , Humanos , Interleucina-1/sangue , Interleucina-17/sangue , Interleucina-1beta/sangue , Interleucina-6/sangue , L-Lactato Desidrogenase/sangue , Masculino , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia
7.
Neuroscience ; 155(2): 469-75, 2008 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-18601983

RESUMO

Blocking specific K+ channels has been proposed as a promising strategy for the treatment of neurodegenerative diseases. Using a computational virtual screening approach and electrophysiological testing, we found four Aconitum alkaloids are potent blockers of the delayed rectifier K+ channel in rat hippocampal neurons. In the present study, we first tested the action of the four alkaloids on the voltage-gated K+, Na+ and Ca2+ currents in rat hippocampal neurons, and then identified that talatisamine is a specific blocker for the delayed rectifier K+ channel. External application of talatisamine reversibly inhibited the delayed rectifier K+ current (IK) with an IC50 value of 146.0+/-5.8 microM in a voltage-dependent manner, but exhibited very slight blocking effect on the voltage-gated Na+ and Ca2+ currents even at the high concentration of 1-3 mM. Moreover, talatisamine exerted a significant hyperpolarizing shift of the steady-state activation, but did not influence the steady state inactivation of IK and its recovery from inactivation, suggesting that talatisamine had no allosteric action on IK channel and was a pure blocker binding to the external pore entry of the channel. Our present study made the first discovery of potent and specific IK channel blocker from Aconitum alkaloids. It has been argued that suppressing K+ efflux by blocking IK channel may be favorable for Alzheimer's disease therapy. Talatisamine can therefore be considered as a leading compound worthy of further investigations.


Assuntos
Aconitina/análogos & derivados , Canais de Potássio de Retificação Tardia/antagonistas & inibidores , Canais de Potássio de Retificação Tardia/fisiologia , Hipocampo/fisiologia , Bloqueadores dos Canais de Potássio/farmacologia , Células Piramidais/fisiologia , Aconitina/química , Aconitina/farmacologia , Alcaloides/farmacologia , Animais , Canais de Cálcio/fisiologia , Medicamentos de Ervas Chinesas/farmacologia , Hipocampo/citologia , Ativação do Canal Iônico/efeitos dos fármacos , Cinética , Potenciais da Membrana/efeitos dos fármacos , Técnicas de Patch-Clamp , Bloqueadores dos Canais de Potássio/química , Ratos , Ratos Sprague-Dawley , Canais de Sódio/fisiologia
8.
Phys Rev Lett ; 88(10): 101802, 2002 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-11909342

RESUMO

We report values of R = sigma(e(+)e(-)-->hadrons)/sigma(e(+)e(-)-->mu(+)mu(-)) for 85 center-of-mass energies between 2 and 5 GeV measured with the upgraded Beijing Spectrometer at the Beijing Electron-Positron Collider.

9.
Neuroscience ; 105(3): 663-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11516831

RESUMO

Huperzine A, a nootropic alkaloid isolated from a Chinese herb, has been proposed as one of the most promising agents to treat Alzheimer's disease. Recently, the agent was found to inhibit the N-methyl-D-aspartate (NMDA) receptors in rat cerebral cortex in addition to causing an inhibitory effect on acetylcholinesterase. In the present study, the mechanisms underlying NMDA receptor inhibition were investigated using whole-cell voltage-clamp recording in CA1 pyramidal neurons acutely dissociated from rat hippocampus. Huperzine A reversibly inhibited the NMDA-induced current (IC(50)=126 microM, Hill coefficient=0.92), whereas it had no effect on the current induced by alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate or kainate. The effect was non-competitive, and showed neither 'voltage-dependency', nor 'use-dependency'. The IC(50) values of huperzine A were neither altered by changing the concentrations of glycine (2-0.2 microM) and pH (7.4-6.7) in the external solution, nor by addition of Zn(2+) (5 microM) and dithiothreitol (5 mM) to the external solution. However, addition of spermine (200 microM) to the external solution caused a parallel shift to the right of the huperzine A concentration-response curve. From these we suggest that huperzine A acts as a non-competitive antagonist of the NMDA receptors, via a competitive interaction with one of the polyamine binding sites. The potential relevance of NMDA receptor antagonist activity of huperzine A to the treatment of Alzheimer's disease is discussed.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Hipocampo/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Nootrópicos/farmacologia , Células Piramidais/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Sesquiterpenos/farmacologia , Alcaloides , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Animais , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/metabolismo , Ditiotreitol/farmacologia , Relação Dose-Resposta a Droga , Agonistas de Aminoácidos Excitatórios/farmacologia , Glicina/farmacologia , Hipocampo/metabolismo , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Ácido Caínico/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , N-Metilaspartato/farmacologia , Técnicas de Patch-Clamp , Células Piramidais/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/agonistas , Receptores de N-Metil-D-Aspartato/metabolismo , Espermina/farmacologia , Zinco/farmacologia , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/farmacologia
11.
Neurosci Lett ; 295(3): 116-8, 2000 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-11090988

RESUMO

The inhibition of huperzine A, a potential therapeutic agent to treat Alzheimer's disease, on rat cortical acetylcholinesterase was found to be highly stereospecific. In the present study the effect of the enantiomers of huperzine A on [(3)H]dizocilpine (MK-801) binding to synaptic membrane of rat cerebral cortex was compared. The natural (-)-huperzine A and the synthetic (+)-huperzine A inhibited the specific binding of [(3)H]MK-801 with a similar potency. The IC(50) values were 65+/-7 and 82+/-12 microM (n=5 for each enantiomer, P=0.248), respectively. The result indicates that huperzine A inhibits N-methyl-D-aspartate (NMDA) receptor in rat cerebral cortex without stereoselectivity.


Assuntos
Sítios de Ligação/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Maleato de Dizocilpina/farmacocinética , Fármacos Neuroprotetores/farmacologia , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Sesquiterpenos/farmacologia , Membranas Sinápticas/efeitos dos fármacos , Alcaloides , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Sítios de Ligação/fisiologia , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Inibidores da Colinesterase/farmacologia , Interações Medicamentosas/fisiologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/química , Ensaio Radioligante , Ratos , Receptores de N-Metil-D-Aspartato/metabolismo , Sesquiterpenos/química , Estereoisomerismo , Membranas Sinápticas/metabolismo
12.
Life Sci ; 67(11): 1265-74, 2000 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-10972195

RESUMO

(-)-Stepholidine (SPD), with D1 agonistic action, elicited an excitatory firing activity of nucleus accumbens (NAc) neurons by intravenous administration, but this effect was hardly observed by iontophoresis of SPD into the NAc. The present study intends to determine whether D1 receptors in the medial prefrontal cortex (mPFC) are involved in the action of SPD on the firing activity of NAc neurons in the chloral hydrate-anesthetized male rats. The results showed that the intra-mPFC microinjected SCH-23390 (D1 antagonist, 30 mM), but not the D2 antagonist spiperone (30 mM), significantly attenuated the enhanced firing activity induced by intravenous injection of SPD (2 mg/kg). Similarly, the excitatory firing of NAc neurons was also exhibited by the microinjection of either SPD or D1 agonist SKF-38393 into the mPFC. The SPD-induced excitatory effect was in a dose-dependent way from 277.8 +/- 51.3% (10 mM) to 1105.4 +/- 283.5% (30 mM) of NAc basal firing, which was completely reversed by SCH-23390 (i.v.). Furthermore, the direct D1 agonistic action of SPD on the mPFC neuron was observed with microiontophoresis. These results indicate that SPD possesses a direct agonistic action on the mPFC D1 receptors, by which it modulates the firing activity of NAc neurons.


Assuntos
Berberina/análogos & derivados , Agonistas de Dopamina/farmacologia , Núcleo Accumbens/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Receptores de Dopamina D1/efeitos dos fármacos , Animais , Berberina/farmacologia , Potenciais Evocados , Iontoforese , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Núcleo Accumbens/citologia , Núcleo Accumbens/metabolismo , Córtex Pré-Frontal/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Dopamina D1/metabolismo
13.
Sheng Li Xue Bao ; 52(2): 123-30, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11961581

RESUMO

Our previous work has demonstrated that (-)-stepholidine (SPD) has dual action, ie D(1) agonistic-D(2) antagonistic action on DA receptors in the nigra-striatal dopamine (DA) system. The present study attempted to ascertain its dual action on the mesolimbic DA system. The firing activities of the nucleus accumbens (NAc) neurons were extracellularly recorded with intravenous and iontophoretic administration of the drug in 6-hydroxydopamine (6-OHDA)-lesioned and intact rats. The results showed that SPD produced a consistently biphasic firing of NAc neurons during the cumulative doses of 0.02 2 mg/kg, iv. When the rats were pretreated with D(2) antagonist spiperone, SPD only exerted an increasing effect, which was subsequently reversed by the D(1) antagonist SCH-23390. Moreover, SCH-23390 could prevent the rate of increase elicited by SPD at high doses, presumably due to the D(1) agonistic action of SPD on the activity of NAc neuron. On the other hand, the inhibition of NAc firing elicited by either D(2) agonist LY171555 or D(1)/D(2) agonists apomorphine was completely reversed by SPD, suggesting an antagonistic action of SPD to D(2) receptors. In 6-OHDA-lesioned rats, iontophoresis of SPD also had an inhibitory effect in the majority of NAc neurons (91%) as SKF-38393 did. This inhibition could be completely blocked by the ejection of SCH-23390, but not by spiperone. These results indicate that SPD also has a D(1) agonistic-D(2) antagonistic dual action on NAc neuron activity, which may be beneficial to the treatment of schizophrenia.


Assuntos
Berberina/análogos & derivados , Berberina/farmacologia , Antagonistas dos Receptores de Dopamina D2 , Núcleo Accumbens/fisiologia , Receptores de Dopamina D1/agonistas , Animais , Eletrofisiologia , Masculino , Neurônios/fisiologia , Oxidopamina , Ratos , Ratos Sprague-Dawley
14.
Neurosci Lett ; 272(1): 21-4, 1999 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-10507533

RESUMO

Huperzine A, a selective inhibitor of acetylcholinesterase, was recently demonstrated to exert an antagonist effect on N-methyl-D-aspartate (NMDA) receptor in rat cerebral cortex. In the present study, the effects of six cholinesterase inhibitors, e.g. huperzine A, huperzine B, tacrine, donepezil (E2020), physostigmine and galanthamine on [3H]dizocilpine (MK-801) binding to synaptic membrane of rat cerebral cortex were compared. Their IC50 values (mean +/- SD) were 36.9 +/- 12.1, 316.8 +/- 93.2, 33.2 +/- 3.7, 135.0 +/- 15.1, 50.4 +/- 7.4, and 3344 +/- 295 microM, respectively. The rank order of potency is tacrine approximately huperzine A > physostigmine > donepezil > huperzine B >> galanthamine. There is no correlation between their activities to inhibit [3H]MK-801 binding and to inhibit acetylcholinesterase (r = +0.563, P = 0.245). The results suggest that most cholinesterase inhibitors available exhibit an antagonist effect on NMDA receptor in rat cerebral cortex in addition to their inhibitory effect on acetylcholinesterase.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Inibidores da Colinesterase/farmacologia , Maleato de Dizocilpina/metabolismo , Antagonistas de Aminoácidos Excitatórios/metabolismo , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Córtex Cerebral/metabolismo , Concentração Inibidora 50 , Ratos , Ratos Sprague-Dawley
15.
Zhongguo Yao Li Xue Bao ; 20(1): 31-5, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10437121

RESUMO

AIM: To investigate the effects of huperzine A (Hup A) on NMDA receptors in rat cerebral cortex. METHODS: 1) The effect of hup A on NMDA-induced current was studied in acutely dissociated rat hippocampal pyramidal neurons using whole-cell recording. 2) The effect of Hup A on NMDA receptor binding was assessed using [3H] dizocilpine (Diz) binding assay in synaptic membrane preparation of rat cerebral cortex. RESULTS: 1) Hup A reversibly inhibited NMDA-induced current in a concentration-dependent manner with IC50 of 45.4 mumol.L-1. 2) Hup A inhibited the specific binding of [3H]MK-801 to extensively washed synaptic membrane of rat cerebral cortex in a concentration-dependent manner with IC50 of 0.5 (0.1-1.9) mumol.L-1 (n = 4). 3) L-Glutamate 10 mumol.L-1 markedly increased [3H] MK-801 binding. In the presence of L-glutamate, Hup A 0.001-0.1 mumol.L-1 caused a further increase of the binding, whereas Hup A 1-300 mumol.L-1 inhibited the binding in a concentration-dependent manner with IC50 of 12.3 (5.8-26.3) mumol.L-1 (n = 5). CONCLUSION: Hup A acted as an antagonist of NMDA receptor in cerebral cortex in addition to its inhibitory effect on acetylcholinesterase.


Assuntos
Córtex Cerebral/metabolismo , Inibidores da Colinesterase/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Sesquiterpenos/farmacologia , Alcaloides , Animais , Separação Celular , Maleato de Dizocilpina/metabolismo , Hipocampo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Membranas Sinápticas/metabolismo
16.
Zhongguo Yao Li Xue Bao ; 20(11): 979-86, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11270978

RESUMO

AIM: To elucidate the action sites of l-stepholidine (SPD) in the basal ganglia. METHODS: Counting the rotations after intra-nucleus microinjection and recording the neuron firing by microiontophoresis of SPD and DA agonists in the basal ganglia of 6-hydroxydopamine (6-OHDA)-lesioned rats. RESULTS: The DA immunoreactive substance was markedly reduced in the 6-OHDA-lesioned rats. The intra-neostriatum microinjection of apomorphine (Apo, D1/D2), SK&F 38393 (D1), and SPD elicited remarkable rotation, and the characteristics of SK&F 38393-produced rotation were of long latency and long duration. The intra-substantia nigra pars reticulata (SNR) injection of Apo, SK&F 38393, and SPD induced the rotation response, while the selective D2 agonist quinpirole hydrochloride (Ly171555) did not because of scarce D2 receptors in the SNR. The intraglobus pallidus (GP) injection of DA agonists and SPD failed to evoke rotation, but the GP nucleus still had the contribution to rotation elicited by i.p. injection of DA agonists and SPD in the 6-OHDA-lesioned rats with successive kainic acid (KA) lesion. Besides, the successive lesion of entopeduncular nucleus (EP) on rotation was less important than that of GP nucleus. The microiontophoresis of Apo and SPD into the SNR could evoke the neuron firing, but failed to activate the GP neurons, which were activated by sodium glutamate (Glu) and inhibited by gamma-aminobutyric acid (GABA). CONCLUSION: The action sites of SPD-induced rotation and neuron firing via the D1 receptors are in the neostriatum and SNR instead of GP. The direct neurocircuit through SNR is the most important for rotation of 6-OHDA-lesioned rats.


Assuntos
Berberina/análogos & derivados , Berberina/farmacologia , Agonistas de Dopamina/farmacologia , Rotação , Substância Negra/fisiologia , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/farmacologia , Animais , Apomorfina/farmacologia , Antagonistas de Dopamina/farmacologia , Eletrofisiologia , Masculino , Neostriado/fisiologia , Oxidopamina , Ratos , Ratos Sprague-Dawley
17.
Zhongguo Yao Li Xue Bao ; 19(1): 31-5, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10375754

RESUMO

AIM: To study the effects of the K+ channel opener pinacidil on 5-HT3 receptor-mediated contractions of the isolated guinea pig ileum (GPI) longitudinal muscle-myenteric plexus strip preparations. METHODS: GPI contractions were recorded with a chart recorder through isometric transducers. The effect of pinacidil on binding properties of 5-HT3 receptors was assessed using [3H]GR65630 binding assay in membrane preparations of rat entorhinal cortex. RESULTS: (1) A selective 5-HT3 receptor agonist 2-methyl-5-HT 0.1-300 mumol.L-1 and 5-HT 0.001-50 mumol.L-1 elicited GPI contractile responses in concentration-dependent manners, the EC50 values (and 95% confidence limits) for 2-methyl-5-HT and 5-HT were 10.0 (8.9-11.2) mumol.L-1 and 1.6 (1.3-1.9) mumol.L-1, respectively. Selective 5-HT3 receptor antagonist tropisetron 0.1 mumol.L-1 competitively inhibited the responses to 2-methyl-5-HT and 5-HT. (2) Pinacidil 0.5-5 mumol.L-1 inhibited 5-HT3 receptor-mediated contractions. (3) Pinacidil 1 mumol.L-1 enhanced the inhibitory effects of tropisetron 0.1 mumol.L-1 or another selective 5-HT3 receptor antagonist benesetron 1 mumol.L-1 on 5-HT-induced GPI contractile responses. (4) Pinacidil 1-5 mumol.L-1 did not affect GPI contractile responses evoked by a selective M-ACh receptor agonist carbachol 1 mumol.L-1. (5) Pinacidil 1-5 mumol.L-1 had no effect on binding properties of 5-HT3 receptors with selective 5-HT3 receptor radioligand [3H]GR65630 in the entorhinal cortex of rat brain. CONCLUSION: The inhibition by pinacidil of 5-HT3 receptor-mediated GPI contractile responses may be mediated through activation of ATP-sensitive K+ channels located in prejunctional myenteric neurons.


Assuntos
Contração Muscular/efeitos dos fármacos , Pinacidil/farmacologia , Canais de Potássio/agonistas , Antagonistas da Serotonina , Animais , Carbacol/antagonistas & inibidores , Cobaias , Íleo/efeitos dos fármacos , Masculino , Músculo Liso/efeitos dos fármacos , Plexo Mientérico/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores de Serotonina , Serotonina/análogos & derivados , Serotonina/farmacologia , Agonistas do Receptor de Serotonina
18.
Zhongguo Yao Li Xue Bao ; 19(4): 317-21, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10375775

RESUMO

AIM: To purify and characterize a potassium channel blocker (BmP-3) from the venom of Chinese scorpion Buthus martensii Karsch. METHODS: 1. Purification was carried out by gel-filtration, cation-exchange, and reversed-phase chromatographies. N-terminal was directly sequenced by double-coupling manual method. Molecular weight was determined on an electrospray ionization mass spectrometer. Amino acid composition was analyzed after acidic hydrolysis for 20 h in HCl 6 mol.L-1 at 110 degrees C. 2. Toxicity tests were conducted in mice and cockroaches. 3. The inhibitory effects of BmP-3 on K+ channels were tested in acutely dissociated rat hippocampal pyramidal neurons using whole-cell patch-clamp configuration. RESULTS: 1. A pure peptide (BmP-3, 8.1 mg) was obtained, about 0.08% of total proteins of the venom. The N-terminal sequences were VGCEE and the molecular weight was 2938 in ESI-mass spectra. 2. No death occurred at the dosage of 200 micrograms in mice and 8 micrograms in cockroaches. 3. The peptide at 10 mumol.L-1 reduced the peak outward K+ currents by 63% +/- 4% in vitro. CONCLUSION: BmP-3 inhibited K+ channels.


Assuntos
Bloqueadores dos Canais de Potássio , Venenos de Escorpião/química , Venenos de Escorpião/isolamento & purificação , Sequência de Aminoácidos , Animais , Baratas , Hipocampo/fisiologia , Masculino , Camundongos , Dados de Sequência Molecular , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley , Venenos de Escorpião/farmacologia , Venenos de Escorpião/toxicidade , Alinhamento de Sequência
19.
Zhongguo Yao Li Xue Bao ; 19(4): 327-31, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10375777

RESUMO

AIM: To study the effects of pentobarbital (PB) on acutely dissociated rat sacral dorsal commissural neurons (SDCN). METHODS: Nystatin-perforated patch clamp recording was used. RESULTS: (1) At a holding potential of -40 mV, PB induced inward Cl- current (IPB) in a concentration-dependent manner with a EC50 (95% confidence limits) of 416 (385-477) mumol.L-1 and a Hill coefficient of 1.08. (2) Picrotoxin reversibly blocked IPB. (3) The reversal potential of IPB was close to the Cl- equilibrium potential. (4) PB enhanced GABA-induced Cl- influx (IGABA). In the presence of PB 30 mumol.L-1, the EC50 (95% confidence limits) of IGABA decreased from 6.9 (5.4-8.4) mumol.L-1 to 3.5 (2.9-4.1) mumol.L-1. CONCLUSION: PB had dual effects on SDCN, facilitated GABAA receptor-mediated currents and at higher concentrations induced Cl- influx itself.


Assuntos
Adjuvantes Anestésicos/farmacologia , Canais de Cloreto/efeitos dos fármacos , Pentobarbital/farmacologia , Medula Espinal/fisiologia , Animais , Animais Recém-Nascidos , Moduladores GABAérgicos/farmacologia , Técnicas In Vitro , Neurônios/fisiologia , Técnicas de Patch-Clamp , Ratos , Ratos Sprague-Dawley , Ácido gama-Aminobutírico/farmacologia
20.
Zhongguo Yao Li Xue Bao ; 19(5): 451-5, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10375808

RESUMO

AIM: To study the effects of tetraethylammonium (TEA) and 4-aminopyridine (4-AP) on 5-HT3 receptor-mediated contractions of the isolated guinea pig ileum longitudinal muscle-myenteric plexus strip preparations (GPI). METHODS: GPI contractions were recorded with a chart recorder through isometric transducers. The effect of TEA and 4-AP on binding properties of 5-HT3 receptors was assessed using [3H]GR65630 binding assay in membrane preparation of rat entorhinal cortex. RESULTS: (1) Both TEA 0.5 mmol.L-1 and 4-AP 5 mumol.L-1 increased the spontaneous activity, and elicited contractions of GPI; atropine 10 mumol.L-1 or the selective 5-HT3 receptor antagonist MDL72222 100 mumol.L-1 prevented these effects. (2) Both TEA 0.05-0.5 mmol.L-1 and 4-AP 1-10 mumol.L-1 enhanced GPI contractions induced by the selective 5-HT3 receptor agonists 2-methyl-5-HT in concentration-dependent manners. (3) Both TEA 0.5 mmol.L-1 and 4-AP 5 mumol.L-1 attenuated the inhibitory effects of the selective 5-HT3 receptor antagonists tropisetron 0.1 mumol.L-1 and benesetron 1 mumol.L-1 on 5-HT3 receptor-mediated GPI contractions. (4) Neither TEA 0.1-0.5 mmol.L-1 nor 4-AP 5-10 mumol.L-1 affected GPI contractions evoked by the selective M-ACh receptor agonist carbachol 1 mumol.L-1. (5) TEA 0.5 mmol.L-1 and 4-AP 10 mumol.L-1 had no effect on the properties of binding of the selective 5-HT3 receptor radioligand [3H]GR65630 to 5-HT3 receptors. CONCLUSION: The enhancement by TEA and 4-AP of 5-HT3 receptor-mediated GPI contractile responses was due to blocking K+ channels in prejunctional myenteric neurons.


Assuntos
4-Aminopiridina/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Receptores de Serotonina/fisiologia , Tetraetilamônio/farmacologia , Animais , Cobaias , Íleo/efeitos dos fármacos , Técnicas In Vitro , Masculino , Plexo Mientérico/efeitos dos fármacos , Canais de Potássio , Serotonina/análogos & derivados , Serotonina/farmacologia , Antagonistas da Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologia , Tropanos/farmacologia
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