RESUMEN
Spike activity of neurons in the ventromedial nucleus (VMN) of the hypothalamus in adult (6-8 months) and aged (2 years) male rats was studied by the in vivo extracellular method using stereotaxic insertion of microelectrodes. In all animals, firing frequency of most VMN neurons increased in response to glucose administration. However, in aged rats, the mean baseline and glucose-induced spike frequencies of VMN neurons were lower than in adult animals. These results support the hypothesis that aging is associated with a decrease in the functional activity of hypothalamic neurons.
Asunto(s)
Envejecimiento/psicología , Núcleo Hipotalámico Ventromedial/fisiología , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Envejecimiento/efectos de los fármacos , Animales , Excitabilidad Cortical/efectos de los fármacos , Fenómenos Electrofisiológicos/efectos de los fármacos , Glucosa/farmacología , Hipotálamo/citología , Hipotálamo/efectos de los fármacos , Hipotálamo/fisiología , Insulina/farmacología , Masculino , Neuronas/efectos de los fármacos , Neuronas/fisiología , Ratas , Ratas Wistar , Núcleo Hipotalámico Ventromedial/citología , Núcleo Hipotalámico Ventromedial/efectos de los fármacosRESUMEN
We studied the expression of sirtuin 1 (Sirt1) in the dorsomedial and ventromedial nuclei of the hypothalamus in young (2 months) and old (2 years) rats by immunohistochemical methods and Western blotting. In aged males and females, a decrease in Sirt1 expression in dorsomedial nucleus was observed. In ventromedial nucleus, the expression of Sirt1 did not change with age. The results confirm the hypothesis that aging is associated with a decrease in the content of sirtuins in the hypothalamic nuclei.
