RESUMO
OBJECTIVE: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) identified in China, in December 2019 determines COronaVIrus Disease 19 (COVID-19). Whether or not the virus was present in Italy earlier the first autochthonous COVID-19 case was diagnosed is still uncertain. We aimed to identify anti-SARS-CoV-2 antibodies in sera collected from 4th November 2019 to 9th March 2020, in order to assess the possible spread of the virus in Italy earlier than the first official national diagnosis. PATIENTS AND METHODS: Anti-SARS-CoV-2 antibodies were evaluated in retrospective serum samples from 234 patients with liver diseases (Hep-patients) and from 56 blood donors (BDs). We used two rapid serologic tests which were confirmed by a validated chemoluminescence assay. RESULTS: Via rapid tests, we found 10/234 (4.3%) IgG-positive and 1/234 (0.4%) IgM-positive cases in the Hep-patient group. Two/56 (3.6%) IgG-positive and 2/56 (3.6%) IgM-positive cases were detected in BD group. Chemoluminescence confirmed IgG-positivity in 3 Hep-patients and 1 BD and IgM-positivity in 1 Hep-patient. RNAemia was not detected in any of the subjects, rendering the risk of transfusion transmission negligible. CONCLUSIONS: Our results suggest an early circulation of SARS-CoV-2 in Italy, before the first COVID-19 cases were described in China. Rapid tests have multiple benefits; however, a confirmation assay is required to avoid false positive results.
Assuntos
Anticorpos Antivirais/imunologia , COVID-19/epidemiologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Idoso , Doadores de Sangue , COVID-19/diagnóstico , COVID-19/imunologia , Teste Sorológico para COVID-19 , Feminino , Humanos , Imunoensaio , Itália/epidemiologia , Hepatopatias , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Estudos Retrospectivos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Testes Sorológicos , Fatores de TempoRESUMO
OBJECTIVE: Monoclonal plasma cell proliferative disorders comprise a wide spectrum of diseases associated to clonal B-cell expansion. Serum protein electrophoretic profile (SPEP) and circulating free light chains (FLCs) levels are the mainstay of diseases management. Recently, soluble (s) Syndecan-1 (SDC1, CD138) produced by myeloma plasma cells has been suggested in the monitoring and follow-up of patients with myeloma. The aim of our study is to evaluate sCD138 in addition with FLCs and SPEP for the screening of patients with different evolutive disease pathways. PATIENTS AND METHODS: Sera from 73 patients with monoclonal gammopathy of undetermined significance (MGUS), 120 smoldering and 42 multiple myeloma (SMM and MM, respectively), 70 HCV-related mixed cryoglobulinemia (MC), 35 B-cell non-Hodgkin's lymphoma (B-NHL) and sera from 50 healthy donors (HD), were tested for sCD138, FLCs (assessed by means of ELISA and turbidimetric assay, respectively) and electrophoresis pattern (performed on Capillarys system) for the generation of a novel biomarker score (BS). RESULTS: Our results were grouped according to the two main lines of disease progression (vs. MM or B-NHL): in one group we found BS mean values of 0.2, 3.4, 5.3, 7.1 for HD, MGUS, SMM and MM, respectively; in the other group of 0.2, 4.4, 6.7 for HD, MC and B-NHL. CONCLUSIONS: We showed that BS mean values follow the ingravescence disease status towards the two main lines of progression to cancerous conditions; it could represent an additional useful tool in the management of screening and/or follow-up.
Assuntos
Biomarcadores Tumorais/sangue , Neoplasias de Plasmócitos/diagnóstico , Neoplasias de Plasmócitos/terapia , Sindecana-1/sangue , Adulto , Eletroforese das Proteínas Sanguíneas , Progressão da Doença , Feminino , Humanos , Masculino , Programas de Rastreamento , Gamopatia Monoclonal de Significância Indeterminada , Mieloma Múltiplo/sangue , Neoplasias de Plasmócitos/sangue , Nefelometria e Turbidimetria/métodos , Paraproteinemias/sangue , Valor Preditivo dos Testes , PrognósticoRESUMO
OBJECTIVE: Mixed Cryoglobulinemia is the most well-known Hepatitis C Virus (HCV)-associated extrahepatic manifestation. MC is both an autoimmune and B-lymphoproliferative disorder. Cryoglobulins (CGs) are classified into three groups according to immunoglobulin (Ig) composition: type I is composed of one isotype or Ig class. Type II and type III mixed CGs are immune complexes composed of polyclonal IgGs acting as autoantigens and mono, polyclonal or oligoclonal IgM with rheumatoid factor activity. IgG1 and IgG3 are the predominant subclasses involved. This study shows the simultaneous presence of IgG-RF and IgG3, supporting the hypothesis of an involvement of this subclass in the initiation of early stages of CGs. PATIENTS AND METHODS: We describe a case series of six HCV-positive patients, all of whom had peripheral neuropathy and transient ischemic attacks, presenting cryoprecipitates formed by IgG3 and IgG1. Cryoprecipitate IgG subclass research was carried out by immunofixation electrophoresis by using antisera against IgG1, IgG2, IgG3, and IgG4. RESULTS: Our six patients presented with an immunochemical pattern characterized by the mere presence of IgG1 and IgG3 subclasses with probable RF activity and one of these six patients exhibited monoclonal IgG3 in his cerebrospinal fluid. CONCLUSIONS: We can hypothesize that the IgG passage through the blood-brain barrier could have contributed to the cause of TIAs, through a mechanism involving the precipitation of circulating immune complexes formed by the two subclasses in the intrathecal vessels.
Assuntos
Crioglobulinemia/imunologia , Hepatite C/complicações , Imunoglobulina G/classificação , Doenças do Sistema Nervoso Periférico/etiologia , Idoso , Barreira Hematoencefálica/imunologia , Crioglobulinemia/etiologia , Feminino , Hepatite C/imunologia , Humanos , Imunoglobulina G/metabolismo , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso Periférico/imunologia , Fator Reumatoide/metabolismoRESUMO
BACKGROUND: Cryoglobulinaemic vasculitis (CV) is a lymphoproliferative disorder related to hepatitis C virus (HCV) infection; anti-viral therapy is the first therapeutic option. CV can be incapacitating, compromising the patients' quality of life (QoL). In a controlled study, interferon-based therapy was associated with a lower virological response in vasculitic patients than in patients without vasculitis. Limited, uncontrolled data on direct-acting anti-virals are available. AIM: To evaluate safety, clinical efficacy, virological response and the impact of interferon-free treatment on QoL in HCV patients with and without mixed cryoglobulinaemia (MC). METHODS: We prospectively studied HCV patients with cryoglobulinaemia (with vasculitis-CV- and without vasculitis-MC-) and without cryoglobulinaemia (controls), treated with direct-acting anti-virals. Hepato-virological parameters, CV clinical response and impact on QoL were assessed. RESULTS: One hundred and eighty-two HCV patients were recruited (85 with CV, 54 with MC and 43 controls). A sustained virological response at 12 weeks (SVR12) was achieved in 166 (91.2%) patients (77/85 CV, 48/54 MC, 41/43 controls). In CV SVR patients, cryocrit levels progressively decreased and clinical response progressively improved, reaching 96.7%, 24 weeks after treatment. QoL, baseline physical and mental component summaries were lower in the CV group compared to the other groups (P < 0.05). Scores improved in all groups, and significantly in CV patients after SVR. CONCLUSIONS: No significant differences in SVR rates were recorded between cryoglobulinaemic patients and controls and a high clinical and immunological efficacy was confirmed in CV, supporting the role of interferon-free therapy as the first therapeutic option. Interestingly, CV patients had worse baseline QoL than other HCV-positive groups and interferon-free therapy was effective in significantly increasing QoL, suggesting the important role of direct-acting anti-viral-based therapy in improving CV's individual and social burden.
Assuntos
Antivirais/uso terapêutico , Crioglobulinemia/tratamento farmacológico , Crioglobulinemia/virologia , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Adulto , Idoso , Feminino , Hepacivirus/fisiologia , Humanos , Imunoterapia , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Resposta Viral Sustentada , Resultado do TratamentoRESUMO
The host genetic basis of mixed cryoglobulin vasculitis is not well understood and has not been studied in large cohorts. A genome-wide association study was conducted among 356 hepatitis C virus (HCV) RNA-positive individuals with cryoglobulin-related vasculitis and 447 ethnically matched, HCV RNA-positive controls. All cases had both serum cryoglobulins and a vasculitis syndrome. A total of 899 641 markers from the Illumina HumanOmni1-Quad chip were analyzed using logistic regression adjusted for sex, as well as genetically determined ancestry. Replication of select single-nucleotide polymorphisms (SNPs) was conducted using 91 cases and 180 controls, adjusting for sex and country of origin. The most significant associations were identified on chromosome 6 near the NOTCH4 and MHC class II genes. A genome-wide significant association was detected on chromosome 6 at SNP rs9461776 (odds ratio=2.16, P=1.16E-07) between HLA-DRB1 and DQA1: this association was further replicated in additional independent samples (meta-analysis P=7.1 × 10(-9)). A genome-wide significant association with cryoglobulin-related vasculitis was identified with SNPs near NOTCH4 and MHC Class II genes. The two regions are correlated and it is difficult to disentangle which gene is responsible for the association with mixed cryoglobulinemia vasculitis in this extended major histocompatibility complex region.
Assuntos
Crioglobulinas/análise , Hepatite C/complicações , Polimorfismo de Nucleotídeo Único , Vasculite/genética , Estudos de Casos e Controles , Cromossomos Humanos Par 6/genética , Crioglobulinemia/etiologia , Crioglobulinemia/genética , Feminino , Genes MHC da Classe II , Estudo de Associação Genômica Ampla , Humanos , Masculino , Proteínas Proto-Oncogênicas/genética , Receptor Notch4 , Receptores Notch/genética , Vasculite/etiologiaRESUMO
HCV-related mixed cryoglobulinemia (MC) is characterized by clonal expansion of B cells producing a polyreactive natural antibody (rheumatoid factor) and interferon (IFN)-based therapy is the first therapeutic option in mild-moderate MC. Single nucleotide polymorphisms (SNPs) proximal to genes involved in the innate response (IL28B/IFN-λ gene family) are strongly associated with spontaneous and IFN-induced viral clearance in hepatitis C, but no data exist about their role in HCV-positive MC. A large cohort of patients with HCV and MC was studied to evaluate the influence of IL28B genotype on the response to treatment and/or the evolution to MC of HCV infection. The rs12979860/rs8099917 IL28B polymorphisms were analysed in 481 consecutive HCV-positive subjects (250 with MC and 231 without MC, as controls) using real-time PCR and direct sequencing. Hundred and fifteen HCV patients with MC received standard anti-HCV therapy, and the results were evaluated according to the IL28B SNP distribution. Similar IL28B SNPs allele frequencies were recorded for patients and controls. IL28B major allele homozygosis (for both SNPs tested) was tightly correlated with virological and clinical response (P = 0.002). A statistically significant association was limited to 'difficult-to-treat' (G1/4) HCV genotypes. The IL28B genotype was a strong independent predictor of response (P = 0.007, OR 6.06; CI 1.65-22.22). The IL28B genotype was confirmed to be a useful predictor of response to IFN-based therapy in patients with HCV and MC. The very close correlation between IL28B SNP distribution, virological and clinical response definitively confirmed the key role played by HCV in MC. Conversely, the IL28B genotype does not seem to influence the evolution to MC.
Assuntos
Crioglobulinemia/genética , Hepatite C Crônica/complicações , Interleucinas/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Feminino , Genótipo , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferons/uso terapêutico , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Resultado do TratamentoRESUMO
The possibility that HCV infects lymphoid cells has been widely discussed. Evidence in favor of HCV tropism for lymphoid cells derives from a series of data including: (1) the higher sensitivity of testing HCVRNA in PBMC than in serum or plasma samples, with possible detection of HCV RNA-positive PBMC in the absence of HCV viremia; (2) short-term cultures of PBMC which yield a significant increase in the amount of viral RNA on stimulation by mitogens; (3) results of "in situ" methods (i.e. in situ hybridization, immunofluorescence); (4) efficient infection of lymphoid cell lines or PBMC from normal individuals; (5) the persistence of HCV RNA in PBMC obtained from HCV-positive subjects and injected into SCID mice; (6) the long-term persistence of HCV RNA in PBMC in spite of HCV RNA negativity of serum and liver in sustained responder patients after therapy. The principal criticisms concerning effective HCV infection of lymphoid cells arise from technical difficulty in identifying HCV RNA replicative intermediate in these elements. Conflicting data may also result from differences in PBMC infection by different genotypes, samples taken at different stages in the disease process and differences in the sensitivity of detection methods, as well as low replication levels and/or proportion of infected PBMC. Interesting available data about HCV lymphotropism, which is possibly important in influencing the natural history of infection, include: (1) possible preferential viral tropism for specific PBMC subsets; (2) different lymphotropism of different viral strains; (3) selection of distinctive viral strains; (4) identification of putative HCV cell receptors; (5) association between determination of HCV lymphatic infection and t(14; 18) translocation. The clinical correlates of HCV lymphotropism are potentially very numerous, including, first, its role in determining HCV-related lymphoproliferative disorders.
Assuntos
Hepacivirus/fisiologia , Linfócitos/virologia , Hepacivirus/genética , Humanos , Leucócitos Mononucleares/virologia , RNA Viral/análiseRESUMO
Hepatitis C virus (HCV) chronically infects about 200 million individuals worldwide and leads to severe liver and lymphatic diseases. HCV circulates in the serum, associated with apoB-containing lipoproteins. Platelet-activating factor (PAF), a pro-inflammatory mediator, is mainly modulated by plasma PAF-acetylhydrolase (pPAF-AH), associated with ApoB100-containing low-density lipoproteins (LDL). The aim of the study was to evaluate the potential effects of chronic HCV infection on the PAF/pPAF-AH system. HCV-RNA was detected in plasma, peripheral blood mononuclear cells (PBMC) and liver samples. Plasma PAF levels, pPAF-AH activity, ApoB100 serum titres and pPAF-AH mRNA levels in cultured macrophages were determined. Plasma PAF levels were significantly higher and pPAF-AH activity was significantly lower in HCV patients than in controls. No significant modifications of pPAF-AH mRNA in macrophages or in ApoB100 values were observed in HCV patients compared with controls. Patients who cleared HCV after antiviral treatment showed a complete restoration of pPAF-AH activity and significant decrease of PAF levels during the follow-up. No data exist about the PAF/pPAF-AH system behaviour during HCV infection. This study shows that in HCV patients modifications of pPAF-AH activity/PAF levels take place and that HCV clearance restored pPAF-AH activity. This suggests that circulating viral particles play a role in PAF/pPAF-AH system modifications and such an alteration could be involved in HCV-related damage.
Assuntos
1-Alquil-2-acetilglicerofosfocolina Esterase/sangue , Hepacivirus/crescimento & desenvolvimento , Hepatite C Crônica/sangue , Fator de Ativação de Plaquetas/metabolismo , 1-Alquil-2-acetilglicerofosfocolina Esterase/genética , Antivirais/uso terapêutico , Apolipoproteína B-100/sangue , Feminino , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Humanos , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , RNA Mensageiro/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Viremia/sangue , Viremia/tratamento farmacológico , Viremia/virologiaAssuntos
Carcinoma Hepatocelular/cirurgia , Hepatite C/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Linfócitos B/imunologia , Carcinoma Hepatocelular/virologia , Hepatite C/complicações , Hepatite C/imunologia , Humanos , Neoplasias Hepáticas/virologia , Transtornos Linfoproliferativos/virologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/virologiaRESUMO
Integrin receptors have been demonstrated to mediate either "inside-to-out" and "outside-to-in" signals, and by this way are capable of regulating many cellular functions, such as cell growth and differentiation, cell migration, and activation. Among the various integrin-centered signaling pathways discovered so far, we demonstrated that the modulation of the electrical potential of the plasma membrane (V(REST)) is an early integrin-mediated signal, which is related to neurite emission in neuroblastoma cells. This modulation is sustained by the activation of HERG K(+) channels, encoded by the ether-à-go-go-related gene (herg). The involvement of integrin-mediated signaling is being discovered in the hemopoietic system: in particular, osteoclasts are generated as well as induced to differentiate by interaction of osteoclast progenitors with the stromal cells, through the involvement of integrin receptors. We studied the effects of cell interaction with the extracellular matrix protein fibronectin (FN) in a human leukemic preosteoclastic cell line (FLG 29.1 cells), which has been demonstrated to express HERG currents. We report here that FLG 29.1 cells indeed adhere to purified FN through integrin receptors, and that this adhesion induces an osteoclast phenotype in these cells, as evidenced by the appearance of tartrate-resistant acid phosphatase, as well as by the increased expression of CD51/alpha(v)beta(3) integrin and calcitonin receptor. An early activation of HERG current (I(HERG)), without any increase in herg RNA or modifications of HERG protein was also observed in FN-adhering cells. This activation is apparently sustained by the beta(1) integrin subunit activation, through the involvement of a pertussis-toxin sensitive G(i) protein, and appears to be a determinant signal for the up-regulation of alpha(v)beta(3) integrin, as well as for the increased expression of calcitonin receptor.
Assuntos
Proteínas de Transporte de Cátions , Adesão Celular , Proteínas de Ligação a DNA , Fibronectinas/metabolismo , Integrina beta1/fisiologia , Osteoclastos/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Canais de Potássio/metabolismo , Receptores de Vitronectina/genética , Transativadores , Anticorpos Monoclonais/imunologia , Diferenciação Celular , Canal de Potássio ERG1 , Condutividade Elétrica , Canais de Potássio Éter-A-Go-Go , Proteínas Filagrinas , Humanos , Integrina beta1/imunologia , Leucemia , Osteoclastos/citologia , Técnicas de Patch-Clamp , Canais de Potássio/genética , RNA Mensageiro/biossíntese , Receptores da Calcitonina/biossíntese , Receptores da Calcitonina/genética , Receptores de Vitronectina/biossíntese , Células-Tronco/citologia , Células-Tronco/metabolismo , Regulador Transcricional ERG , Células Tumorais Cultivadas , Regulação para CimaRESUMO
A population of 56 cases of acute delusional disorders classified Bouffées délirantes by Pichot's diagnostic criteria is studied. Diagnostic methodology is described. Prognostic factors are assessed from individual variables, using a logistic linear regression model giving the probability of a favourable outcome. These prognostic factors are then adjusted considering gender.
Assuntos
Delusões/classificação , Transtornos Psicóticos/classificação , Doença Aguda , Adaptação Psicológica , Adolescente , Adulto , Delusões/diagnóstico , Delusões/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/psicologia , Estudos Retrospectivos , Esquizofrenia/classificação , Esquizofrenia/diagnóstico , Psicologia do EsquizofrênicoRESUMO
Stress-induced hyperthermia (SIH), which is seen in the last mice removed from the cage, is a novel animal model sensitive to anxiolytic drugs. SIH is antagonized by CL 218872 (25 and 50 mg/kg, os), by tracazolate (5 and 7.5 mg/kg, ip) and by 2-AP-5 (50 and 100 mg/kg, ip). At higher dose, CL 218872 (100 mg/kg, os) and tracazolate (12.5 mg/kg, ip) lose their activity. PK 9084 (5-40 mg/kg, ip) and CGS 9896 (2-20 mg/kg, both ip and os) were also ineffective in preventing SIH. The anti-hyperthermic effect of CL 218872 (25 mg/kg) and tracazolate (7.5 mg/kg) was blocked by the benzodiazepine antagonist Ro 15-1788 (15 mg/kg), CGS 9896 (10 mg/kg, os) also reversed the effect of CL 218872 (25 mg/kg) on SIH. Differently from anxiolytics, MK-801 (0.5-1 mg/kg, os), PCP (2.5 mg/kg, ip) and d-amphetamine (10 mg/kg, ip) evoked hyperthermia in the first set of mice and prevented a further stress-induced rise of body temperature in the last set of mice.
Assuntos
Ansiolíticos/farmacologia , Febre/prevenção & controle , Estresse Fisiológico/fisiopatologia , 2-Amino-5-fosfonovalerato/farmacologia , Animais , Temperatura Corporal/efeitos dos fármacos , Dextroanfetamina/farmacologia , Maleato de Dizocilpina/farmacologia , Febre/etiologia , Flumazenil/farmacologia , Masculino , Camundongos , Fenciclidina/farmacologia , Pirazóis/farmacologia , Piridazinas/farmacologia , Quinolinas/farmacologia , Receptores de GABA-A/efeitos dos fármacos , Receptores de Serotonina/efeitos dos fármacos , Método Simples-Cego , Estresse Fisiológico/complicaçõesRESUMO
Acute imipramine administration (15 mg/kg i.p. 60 min before) increased the threshold for activating the spinal but not the supraspinal vesico-vesical micturition reflex in urethane-anesthetized rats. On the other hand, "chronic" imipramine administration (15 mg/kg i.p./day for 5 consecutive days) increased selectively the threshold of the supraspinal micturition reflex. Intravenous administration of cumulative doses of imipramine (up to 14 mg/kg) exerted a progressive inhibitory effect on the supraspinal reflex and voiding efficiency, possibly related to direct inhibition of muscular contractility at the bladder level. However, with the dose regimen used to compare the action of imipramine on spinal and supraspinal reflexes (15 mg/kg i.p., 60 min before), imipramine did not affect the volume-pressure curve or myogenic activity in decentralized bladders (bilateral removal of pelvic ganglia). The effect of acute imipramine on threshold of the spinal vesico-vesical reflex was absent in rats receiving oral p-chlorophenylalanine to deplete 5-hydroxytryptamine stores in the central nervous system. On the other hand, p-chlorophenylalanine pretreatment did not prevent the action of chronic imipramine administration on the supraspinal reflex. Acute administration of desipramine, the major metabolite of imipramine, increased threshold of the spinal but not supraspinal micturition reflex. These findings indicate that the ability of imipramine to modulate vesico-urethral motility at the central nervous system level may involve different mechanisms. Inhibition of 5-hydroxytryptamine reuptake in nerve terminals may be important for the acute modulatory effect of imipramine on the spinal reflex.
Assuntos
Imipramina/farmacologia , Reflexo/efeitos dos fármacos , Medula Espinal/fisiologia , Micção/efeitos dos fármacos , Animais , Atropina/farmacologia , Desipramina/farmacologia , Enurese/prevenção & controle , Fenclonina/farmacologia , Masculino , Ratos , Receptores de Serotonina/fisiologia , Medula Espinal/efeitos dos fármacos , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/fisiologiaRESUMO
SC-19220 (5-20 mg/kg i.v.), a competitive receptor antagonist of PGE, increased the bladder capacity and reduced the voiding efficiency of micturition (elicited by slow transvesical filling) of urethane-anesthetized rats. The effect of SC-19220 was prevented by indomethacin pretreatment, whereas indomethacin per se mimicked the effects of SC-19220. SC-19220 produced a competitive rightward shift of the dose-response curve for the contractile effect induced by PGE2 on strips of rat detrusor muscle in vitro, whereas the amplitude of nerve-mediated twitches was unaffected. These findings support the hypothesis that endogenous PGE2 is physiologically involved in the regulation of vesicourethral motility in this species by facilitating attainment of the micturition threshold during the collection phase of the cystometrogram.
Assuntos
Ácido Dibenzo(b,f)(1,4)oxazepina-10(11H)-carboxílico, 8-cloro-, 2-acetilidrazida/farmacologia , Dibenzoxazepinas/farmacologia , Antagonistas de Prostaglandina/farmacologia , Reflexo/efeitos dos fármacos , Animais , Dinoprostona/farmacologia , Técnicas In Vitro , Indometacina/farmacologia , Masculino , Ratos , Ratos Endogâmicos , Micção/efeitos dos fármacosRESUMO
Topical application of exogenous prostanoids (PGE2, TBX B2) on the serosal surface of the urinary bladder of urethane-anaesthetized rats activated reflex micturition. Likewise, intravesical instillation of PGE2 during the cystometrogram lowered the threshold for reflex micturition. Both effects were prevented by systemic capsaicin desensitization (50 mg/kg s.c., 4 days before). Indomethacin pretreatment and systemic capsaicin desensitization each increased the micturition threshold without affecting the amplitude of micturition contraction. However, the effect of the two treatments combined was not greater than the effect of either alone. These findings support the idea that endogenous prostanoids facilitate reflex micturition by stimulating or sensitizing, directly or indirectly, the subset of bladder mechanoreceptors which is capsaicin-sensitive in adult rats.
Assuntos
Capsaicina/farmacologia , Prostaglandinas E/fisiologia , Reflexo/efeitos dos fármacos , Tromboxano B2/fisiologia , Micção/efeitos dos fármacos , Animais , Dinoprostona , Indometacina/farmacologia , Masculino , Prostaglandinas E/administração & dosagem , Prostaglandinas E/farmacologia , Ratos , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/inervaçãoRESUMO
1. The effect of (+/-)-baclofen on micturition reflexes was investigated in urethane-anaesthetized rats. A 'low' dose of (+/-)-baclofen (0.5 mg/kg i.v.) barely affected the early phase of the transurethral cystometrogram (CMG) which involves activation of a spinal vesico-vesical excitatory reflex. 2. At a higher dose (2.5 mg/kg i.v.) (+/-)-baclofen suppressed both the spinal and supraspinal components of the bladder response to transurethral saline filling. 3. When the bladder was filled by the transvesical route a series of regular voiding cycles was obtained which are due to activation of a supraspinal vesico-vesical excitatory reflex. In this model, voiding efficiency of the rat bladder was markedly reduced even after a low dose of (+/-)-baclofen (0.5 mg/kg) and almost suppressed at 2.5 mg/kg. 4. (+/)-Baclofen reduction of voiding efficiency was mainly ascribable to an inhibitory effect on the expulsive phase of the voiding cycle which, in rats, depends critically upon the activation of a reflex which induces a twitch-like contraction of urethral/periurethral skeletal muscles. 5. (+/-)-Baclofen produced a small inhibition of the pinching-induced somatovesical excitatory reflex. (+/-)-Baclofen (2.5 mg/kg i.v.) produced also a marked but transient inhibition of bladder contractions induced by preganglionic nerve stimulation. However the time course of this effect was markedly shorter as compared to the long lasting suppression of voiding cycle observed with this same dose of the drug.(ABSTRACT TRUNCATED AT 250 WORDS)