RESUMO
A double toxin-double lesion strategy is well-known to generate a rat model of striatonigral degeneration (SND) such as multiple system atrophy-parkinsonian type. However, with this model it is difficult to distinguish SND from Parkinson's disease (PD). In this study, we propose a new rat model of SND, which is generated by simultaneous injection of 6-hydroxydopamine into the medial forebrain bundle and quinolinic acid into the striatum. Stepping tests performed 30 min after intraperitoneal L-dopa administration at 6 weeks post-surgery revealed an L-dopa response in the PD group but not the SND group. Apomorphine-induced rotation tests revealed no rotational bias in the SND group, which persisted for 2 months, but contralateral rotations in the PD group. MicroPET scans revealed glucose hypometabolism and dopamine transporter impairment on the lesioned striatum in the SND group. Tyrosine hydroxylase immunostaining in the SND group revealed that 74.7% of nigral cells on the lesioned side were lost after lesion surgery. These results suggest that the proposed simultaneous double toxin-double lesion method successfully created a rat model of SND that had behavioral outcomes, multitracer microPET evaluation, and histological aspects consistent with SND pathology. This model will be useful for future study of SND.
Assuntos
Animais , Masculino , Ratos , Apomorfina/farmacologia , Comportamento Animal/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Modelos Animais de Doenças , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Glucose/metabolismo , Injeções Intraperitoneais , Levodopa/farmacologia , Feixe Prosencefálico Mediano/efeitos dos fármacos , Oxidopamina/toxicidade , Doença de Parkinson/metabolismo , Tomografia por Emissão de Pósitrons , Ácido Quinolínico/toxicidade , Ratos Wistar , Degeneração Estriatonigral/induzido quimicamente , Tato/efeitos dos fármacosRESUMO
BACKGROUND: We investigated whether the intubating condition change acoording to the methods of administration of propofol and rocuronium. METHODS: Ninety adult patients (ASA physical status I or II) undergoing elective surgery were randomly assigned to one of three groups; Group I (n = 30) received rocuronium (0.6 mg/kg) after administration of propofol (2 mg/kg), Group II (n = 30) received propofol and rocuronium simultaneously via different intravenous routes, and Group III (n = 30) received a mixture of propofol and rocuronium via same intravenous route. Intubation was attempted at 60 seconds after administration of rocuronium. Hemodynamic parameters (mean blood pressure, heart rate) were measured before and after propofol administration with 20 seconds interval. Intubating conditions (jaw relaxation, vocal cord movement, and response to tracheal intubation) were evaluated as excellent, good, fair and poor. Train of four counts were recorded at 60 seconds after administration of rocuronium. RESULTS: Excellent intubating conditions were obtained in 13% in group I, 60% in group II, 77% in group III. Mean train of four counts were 3.7 in group I, 3.4 in group II, and 3.5 in group III. Mean blood pressures were decreased gradually after propofol administration in all groups. However, heart rates were not changed in all groups. CONCLUSIONS: At induction of anesthesia, simultaneous or mixed administration of propofol and rocuronium provides excellent or good intubating conditions 60 seconds after rocuronium administration. It could be an effective alternative to succinylcholine for rapid sequence induction of anesthesia.