RESUMO
The aim of this study was to examine the effects of a serotonergic anorectic agent, dexnorfenfluramine (DNOR), on food intake in mice whose meals were constrained to specified periods each day and by effort. Mice were forced to adopt a human-like pattern of regular meals by making food available for four periods of 40 min/24-h period, mostly at night. They lived in behavior test chambers with a closed economy for food and were required to emit a fixed unit price (FUP) of either 2 or 25 nose pokes (FUP2, FUP25) to receive a 20 mg pellet of food. Once responding and intake were stable, mice were injected with a vehicle or DNOR (3 or 6 mg/kg) 1 h before a specified feeding opportunity. Food intake was dose-dependently suppressed at the next meal and to a greater extent when the cost of food was high (FUP25). Within a meal, the effect of the drug was the greatest in the first half of the available time. Therefore, the anorectic effect of DNOR was modified by the concurrent cost of food.
Assuntos
Depressores do Apetite/farmacologia , Comportamento Alimentar/efeitos dos fármacos , Refeições , Neurônios/efeitos dos fármacos , Norfenfluramina/farmacologia , Resposta de Saciedade/efeitos dos fármacos , Antagonistas do Receptor 5-HT2 de Serotonina/farmacologia , Animais , Depressores do Apetite/administração & dosagem , Comportamento Animal/efeitos dos fármacos , Condicionamento Operante , Relação Dose-Resposta a Droga , Ingestão de Energia/efeitos dos fármacos , Injeções Subcutâneas , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Receptor 5-HT2C de Serotonina/química , Receptor 5-HT2C de Serotonina/metabolismo , Recompensa , Antagonistas do Receptor 5-HT2 de Serotonina/administração & dosagem , Fatores de TempoRESUMO
OBJECTIVE: Clinical diagnoses of asthma and reactive airway disease (RAD) in young children are subjective. We examined how often children were diagnosed with asthma versus RAD, and whether preventive care and 2-year clinical outcomes differed based on initial diagnosis. METHODS: We conducted a retrospective cohort analysis of children (2-7 years) from a university-based general pediatrics practice who had been diagnosed with RAD or asthma. We performed adjusted comparisons between groups for time until subsequent asthma-related care. We also compared delivery of asthma-related healthcare services, corticosteroid and controller prescriptions, and action plans within 2 years of index diagnosis, using bivariate and regression analyses. RESULTS: Four hundred three children were included (64% male, 67% Black, 25% Hispanic). RAD was diagnosed in 62% of index visits, and was more likely than asthma to be diagnosed in emergency settings. In the full sample, the time between index visit and subsequent asthma care did not differ between groups, after adjustment for index location. For subjects with complete 24-month follow-up (N = 300), no between-group differences were found in adjusted analyses. Most children with RAD received action plans and controller medications only after a subsequent asthma diagnosis, on average, 9 months after their index visit. CONCLUSIONS: RAD diagnoses were linked to delayed delivery of preventive care measures, but within 2 years of initial diagnosis, clinical outcomes for those diagnosed with RAD and asthma did not differ. To facilitate clear communication and timely treatment, a prompt diagnosis of asthma, rather than RAD, should be considered for children with asthma symptoms.