RESUMO
BACKGROUND: Catecholamine secretion by head and neck paragangliomas is uncommon. Dopamine secretion by these tumors has not routinely been assessed. This case report describes a dopamine-secreting glomus vagale and evaluates seven other paragangliomas immunohistochemically for their ability to synthesize dopamine. METHODS: Light microscopic and immunohistochemical studies were performed on eight tumors, and biochemical testing for serum/urine catecholamines was performed on two patients. RESULTS: One patient (case report) had elevated serum dopamine which corrected following surgery. Five tumors stained strongly positive for the presence of tyrosine hydroxylase, the critical enzyme in the biosynthesis of dopamine. CONCLUSION: This case report describes the ability of a glomus vagale to secrete dopamine. Other paragangliomas express the enzymatic machinery necessary to begin catecholamine synthesis. Now that dopamine is routinely screened during catecholamine determination, other cases may be identified.
Assuntos
Corpos Aórticos/metabolismo , Dopamina/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Paraganglioma Extrassuprarrenal/metabolismo , Neoplasias de Cabeça e Pescoço/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Paraganglioma Extrassuprarrenal/diagnóstico , Nervo VagoAssuntos
Cafeína/efeitos adversos , Carcinoma de Células Escamosas/cirurgia , Neoplasias Faríngeas/cirurgia , Complicações Pós-Operatórias , Agitação Psicomotora/etiologia , Síndrome de Abstinência a Substâncias/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Agitação Psicomotora/terapia , Síndrome de Abstinência a Substâncias/terapiaAssuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Fluoruracila/uso terapêutico , Neoplasias Laríngeas/tratamento farmacológico , Septo Nasal/patologia , Neoplasias dos Seios Paranasais/tratamento farmacológico , Neoplasias dos Seios Paranasais/patologia , Neoplasias da Língua/tratamento farmacológico , Idoso , Carcinoma de Células Escamosas/radioterapia , Terapia Combinada , Fluoruracila/administração & dosagem , Glote/patologia , Humanos , Neoplasias Laríngeas/patologia , Masculino , Neoplasias dos Seios Paranasais/radioterapia , Língua/patologiaRESUMO
Auditory brainstem responses (ABRs) were characterized at 37 degrees C in ground squirrels (Citellus lateralis) which were implanted with recording screws to record ABRs, and a thermistor to record brain temperature. After two weeks ground squirrels were reanesthetized and tone pips and clicks were delivered through a TDH-49 headphone. Recorded ABRs were found to vary in a predictable manner as a function of stimulus frequency and intensity. At intensities above 50 dB SPL, ABRs could be recorded over the range tested (2-32 kHz). An 8 kHz tone pip was the best frequency for recording ABRs at the lowest stimulus intensities. Latencies decreased as stimulus frequencies increased from 4 kHz to 32 kHz.
Assuntos
Tronco Encefálico/fisiologia , Potenciais Evocados Auditivos , Sciuridae/fisiologia , Estimulação Acústica , Animais , Limiar Auditivo/fisiologia , Feminino , MasculinoRESUMO
Auditory brainstem responses (ABRs) were recorded in ground squirrels (Citellus lateralis) arousing from hibernation. Squirrels implanted with recording screws to record ABRs, and a thermistor to record brain temperature, were placed in a cold room at 9 degrees C on a 2L:22D light-dark cycle. Hibernating animals were moved from the cold room and ABRs recorded during arousal. The responses showed a gradual development of all brainstem peaks. At low temperatures there were very long latencies to the peaks. The amplitudes of the peaks increased (with fluctuations) as brain temperature increased. The data indicate that neural generators on the brainstem auditory pathway were all activated early in arousal. These results do not support the hypothesis that successive peaks appear and grow in amplitude only after previous peaks are fully developed.
