RESUMO
The search for new nitric oxide donors is warranted by the limitations of organic nitrates currently used in cardiology. The new organic nitrate 2-nitrate-1,3-dibuthoxypropan (NDBP) exhibited promising cardiovascular activities in previous studies. The aim of this study was to investigate the cardiorespiratory responses evoked by NDBP and to compare them to the clinically used organic nitrate nitroglycerine (NTG). Arterial pressure, heart rate and respiration were recorded in conscious adult male Wistar rats. Bolus i.v. injection of NDBP (1 to 15mg/kg; n=8) and NTG (0.1 to 5mg/kg; n=8) produced hypotension. NDBP induced bradycardia at all doses, while NTG induced tachycardia at three lower doses but bradycardia at higher doses. Hydroxocobalamin (20mg/kg; HDX), a NO scavenger, blunted hypotension induced by NDBP (15mg/kg), and its bradycardic effect (n=6). In addition, HDX blunted both hypotension and bradycardia induced by a single dose of NTG (2.5mg/kg; n=6). Both NDBP and NTG altered respiratory rate, inducing a biphasic effect with a bradypnea followed by a tachypnea; HDX attenuated these responses. Our data indicate that NDBP and NTG induce hypotension, bradycardia and bradypnea, which are mediated by nitric oxide release.
Assuntos
Pressão Arterial/efeitos dos fármacos , Fármacos Cardiovasculares/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Nitratos/farmacologia , Propano/análogos & derivados , Respiração/efeitos dos fármacos , Animais , Pressão Arterial/fisiologia , Bradicardia/induzido quimicamente , Bradicardia/tratamento farmacológico , Bradicardia/fisiopatologia , Fármacos Cardiovasculares/administração & dosagem , Estado de Consciência , Relação Dose-Resposta a Droga , Frequência Cardíaca/fisiologia , Hidroxocobalamina/farmacologia , Hipotensão/induzido quimicamente , Hipotensão/tratamento farmacológico , Hipotensão/fisiopatologia , Masculino , Nitratos/administração & dosagem , Óxido Nítrico/metabolismo , Nitroglicerina/administração & dosagem , Nitroglicerina/farmacologia , Propano/administração & dosagem , Propano/farmacologia , Ratos , Ratos Wistar , Taquipneia/induzido quimicamente , Taquipneia/tratamento farmacológico , Taquipneia/fisiopatologia , Vasodilatadores/administração & dosagem , Vasodilatadores/farmacologiaRESUMO
This study evaluated the results of curettage followed by spray propane, butane, and isobutane gas combination cryosurgery in 10 patients with ameloblastoma. The patients' age ranged from 7 to 87 years (mean, 31 years), with equal prevalence in both men and women. Five cases were diagnosed as solid ameloblastomas and 5 as unicystic ameloblastomas. Before enucleation and cryosurgery, the unicystic lesions received marsupialisation to decrease their size. No patient showed evidence of clinical or radiographic recurrence, pathologic fracture, or infection after treatment with enucleation and cryosurgery. The most common complication was wound dehiscence, which was observed in all cases. The average follow-up period was 60.5 months (range 48-108 months). These results show that enucleation followed by cryosurgery is an effective therapy for managing ameloblastomas.