Somatostatin concentrations in discrete hypothalamic nuclei of genetically obese Zucker rats.

Hypothalamic somatostatin concentration was determined in 6.5 to 9 months old male and female genetically obese fatty (fa/fa) and lean (Fa/-) Zucker rats. Similar somatostatin levels were found in fatty and lean animals in the hypothalamic regions previously known to contain the highest hormone levels (median eminence and arcuate, periventricular and ventromedial nuclei). The fatty animals were grossly obese and had a pronounced hyperinsulinemia.