Topographic localisation of insulinogenic and insulinoprival areas in the hypothalamus

Summary Electrical stimulation of hypothalamic areas through stereotaxically implanted electrodes were carried out in conscious male rhesus monkeys. There was a significant increase in immunoreactive insulin (IRI) following lateral hypothalamus (LHA) stimulation. An opposite response was obtained from ventromedial hypothalamus (VMH). Thus, insulinogenic and insulinoprival responses were obtained from feeding and satiety, suggesting a significant role of insulin in the regulation of food intake.     

Oxidative metabolism of the hypothalamus in hypophysectomized-castrated rats

Resumen Los resultados obtenidos han indicado que el incremento del consumo de oxígeno en el hipotálamo anterior y posterior de los animales hipofisectomizados desaparece si estos animales son castrados simultaneamente con la hipofisectomía. Se discute la importancia de la presencia del testículo en la elevación de la actividad metabólica del hipotálamo luego de la hipofisectomía.

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Supported by a grant from the Consejo Nacional de Investigaciones Científicas y Técnicas de la República Argentina.     

The hypothalamus and the neurobiology of drug seeking

The hypothalamus is a neural structure critical for expression of motivated behaviours that ensure survival of the individual and the species. It is a heterogeneous structure, generally recognised to have four distinct regions in the rostrocaudal axis (preoptic, supraoptic, tuberal and mammillary). The tuberal hypothalamus in particular has been implicated in the neural control of appetitive motivation, including feeding and drug seeking. Here we review the role of the tuberal hypothalamus in appetitive motivation. First, we review evidence that different regions of the hypothalamus exert opposing control over feeding. We then review evidence that a similar bi-directional regulation characterises hypothalamic contributions to drug seeking and reward seeking. Lateral regions of the dorsal tuberal hypothalamus are important for promoting reinstatement of drug seeking, whereas medial regions of the dorsal tuberal hypothalamus are important for inhibiting this drug seeking after extinction training. Finally, we review evidence that these different roles for medial versus lateral dorsal tuberal hypothalamus in promoting or preventing reinstatement of drug seeking are mediated, at least in part, by different populations of hypothalamic neurons as well as the neural circuits in which they are located.     

Evidence for a hypocalcemic factor in the hypothalamus

Zusammenfassung Es konnte gezeigt werden, dass ein Hypothalamus-Extrakt von Meerschweinchen an hypophysektomierten Raten eine deutliche Senkung des Plasmakalziums bewirkte.     

Evidence for an adipokinetic mechanism in the ventromedial hypothalamus

Zusammenfassung Nach peroraler Verabreichung von¹⁴C-Glukose konnte in den Lipiden des ventromedialen Hypothalamus mehr Radioaktivität nachgewiesen werden als im lateralen Hypothalamus. Dies könnte ein Hinweis für eine Steuerung der Nahrungsaufnahme über den Lipidmetabolismus des medialen Hypothalamus sein.     

Increased contents of phenylethanolamine, m-octopamine and p-octopamine in the hypothalamus and brain stem of spontanously hypertensive rats (S.H.R. Kyoto)]

Phenylethanolamine, p-octopamine and m-octopamine contents were determined in the hypothalamus and the brain stem of spontaneously hypertensive Rats (S.H.R. Kyto) and the corresponding controls (Wistar Kyoto). In three-week-old Rats, phenylethanolamine and p-octopamine are found to be present in S.H.R. hypothalamus and brain stem at concentrations twice as high as compared to Wistar Kyoto Rats. The amount of m-octopamine is 5-fold higher in the brain stem of S.H.R. Rats as compared to Wistar Kyoto Rats.     

Starvation-induced changes in the autoradiographic localisation of valine uptake by rat small intestine

We report here the effects of a 72-h fast on the localisation of Na-dependent [3H]-valine uptake by rat small intestine. Starvation results in the earlier appearance of valine transport during cell migration and an enhanced accumulation of the amino acid at the villus tip.     

Starvation-induced changes in the autoradiographic localisation of valine uptake by rat small intestine

Summary We report here the effects of a 72-h fast on the localisation of Na-dependent [³H]-valine uptake by rat small intestine. Starvation results in the earlier appearance of valine transport during cell migration and an enhanced accumulation of the amino acid at the villus tip.Acknowledgments. We wish to thank MW Smith, PS James and IS King (AFRC Institute of Animal Physiology, Babraham, Cambridge) for facilities and advice regarding autoradiography. Financial support from the British Digestive Foundation and Eli Lilly and Company is appreciated.