RESUMO
Rats with lesions to the ventromedial hypothalamus (VMH) manifest obesity, hyperphagia, and hyperinsulinemia, and fetal VMH transplantation into the third cerebroventricle of VMH-lesioned rats reduces the development of obesity caused by the lesion. The aim of this study was to determine whether the hyperphagia, hyperlipidemia, and hyperinsulinemia of obsese Zucker rats could be corrected by the transplantation of lean fetal Zucker hypothalamic tissue into the third cerebral ventricle of Zucker obese rats. After the fetal hypothalamic transplant (obese-HY), the rate of weight gain was significantly diminished compared with the unoperated Zucker obese rats and the obese rats that received the transplantation of a similar amount of frontal cortical tissue from the same fetus (obese-FC). Food intake was significantly lower, and plasma triacylglycerol and insulin concentrations were also significantly reduced in the obese-HY rats compared with the obese and obese-FC rats. The weight of the adrenal glands, the plasma adrenocorticotropic hormone concentration, the liver weight, and the liver lipid content in obese-HY were significantly less than those observed in the obese and obese-FC animals. There were no significant differences between the obese and the obese-FC animals or between unoperated Zucker lean rats and lean rats transplanted with lean fetal hypothalamus in all the parameters we determined in this study. Neovascularization and normal cellular morphology of the transplanted fetal hypothalamic tissue suggest that the transplanted neural and glial cells were viable and physiologically functional. In conclusion, this study offers evidence suggesting that the hypothalamic-pituitary-adrenal function is defective in Zucker obese rats, resulting in excessive weight gain, hyperphagia, hyperlipidemia, and hyperinsulinemia. The hypothalamic dysfunction in the Zucker obese rats is corrected by the transplantation of lean fetal hypothalamus.
Assuntos
Transplante de Tecido Fetal , Hipotálamo/embriologia , Hipotálamo/fisiopatologia , Tecido Nervoso/transplante , Obesidade/fisiopatologia , Obesidade/cirurgia , Glândulas Suprarrenais/patologia , Hormônio Adrenocorticotrópico/sangue , Animais , Ingestão de Líquidos , Ingestão de Alimentos , Hipotálamo/patologia , Insulina/sangue , Fígado/metabolismo , Fígado/patologia , Masculino , Obesidade/patologia , Tamanho do Órgão , Ratos , Ratos Zucker , Valores de Referência , Triglicerídeos/sangue , Triglicerídeos/metabolismoRESUMO
Two infants born to mothers who had been given a renal transplant and who were receiving azathioprine and prednisone have been followed up for over 2 years. Initially both had lower than normal lymphocyte counts and cortisol levels. Chromosomal aberrations similar to those found in the lymphocytes of the mothers were present at birth but had disappeared by 32 and 20 months, respectively. The significance of these findings is discussed.
