RESUMEN
To study the effects of clonidine on growth and plasma somatomedin C (SmC) levels, 42 male Wistar rats aged 28 days and weighing 75 to 105 g were given clonidine (1.5 micrograms/ml in drinking water), or filtered water alone and were weighed weekly. After 0, 4 and 8 weeks, the animals were sacrificed under ether anesthesia, their length was measured and blood was collected by cardiac puncture for measurement of SmC concentration. Growth and the weight/length ratio were lower, and plasma SmC levels (mean +/- SEM) were greater in the treated groups after 4 (616 +/- 44.7 vs 433.2 +/- 39.38 ng/ml, P less than 0.01) and 8 (595.2 +/- 28.3 vs 412.66 +/- 39.01 ng/ml, P less than 0.01) weeks of treatment, suggesting that clonidine treatment increased growth hormone secretion. In other experiments, treated animals showed increased food intake only during the first week of treatment and decreased epididymal fat weight after 3 weeks (1.412 +/- 0.0536 vs 1.6 +/- 0.1336 mg/100 g body weight, P less than 0.01). The results suggest that clonidine acts at the level of the central nervous system involving transitory modulation of food intake, as well as on the regulation of energy metabolism.
Asunto(s)
Clonidina/farmacología , Conducta Alimentaria/efectos de los fármacos , Crecimiento/efectos de los fármacos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Animales , Metabolismo Energético , Masculino , Ratas , Ratas Endogámicas , Aumento de Peso/efectos de los fármacosRESUMEN
To study effects of clonidine on growth and plasma somatomedin C (SmC) lelvels, 42 male Wistar rats aged 28 days and weighing 75 to 105 g were given clonidine (1,5 microng/ml in drinking water), or filtered water alone and were weighed weekly. After 0,4 and 8 weeks, the animals were sacrificed under ether anesthesia, their length was measured and blood was collected by cardiac puncture for measurement of SmC concentration. Growth and the weigh/lengh ratio were lower, and plasma SmC levels (mean ñ SEM) were greater in the treated groups after 4 (616 ñ 44.7 vs 433.2 ñ 39.38 ng/ml, P < 0.01) and 8(595.2 28.3 vs 412.66 ñ 39.01 ng/ml, P < 0.01) weeks of treatment, suggesting that clonidine treatment increased growth hormone secretion. In other experiments, treated showed increased food intake only during the first week of treatment and decreased epididymal fat weight afther 3 weeks (1.412 ñ 0.0536 vs 1.6 ñ 0.1335 mg/100 g body weight, P < 0.01). The results suggest that clonidine acts at the level of the central nervous system involving transitory modulation of food intake, as well as on the regulation of energy metabolism
Asunto(s)
Ratas , Animales , Masculino , Clonidina/farmacología , Conducta Alimentaria/efectos de los fármacos , Crecimiento/efectos de los fármacos , Factor I del Crecimiento Similar a la Insulina/sangre , Metabolismo Energético , Ratas Wistar , Aumento de Peso/efectos de los fármacosAsunto(s)
Diabetes Mellitus Tipo 1/complicaciones , Enanismo/etiología , Somatomedinas/metabolismo , Preescolar , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hormona del Crecimiento/análisis , Humanos , Insulina de Acción Prolongada/administración & dosificación , Insulina de Acción Prolongada/uso terapéutico , MasculinoRESUMEN
Plasma prednisolone levels have been measured hourly in children receiving a single dose of oral prednisone. Peak prednisolone levels occurred one to two hours after ingestion; half-life studies gave a mean value of 132 minutes in most children. Some children had marked variability in absorption and metabolism of prednisone. Somatomedin activity and cell-mediated immunity were inhibited by plasma prednisolone values which were achieved by single doses of prednisone of 0.5 mg/kg or higher. Monitoring prednisolone levels may be of value in identifying those children who accumulate excessively high levels on moderate dosage regimens.