Somatomedins in aging and dementia disorders of the Alzheimer type.

Serum levels of somatomedins were determined in apparently healthy aged individuals and dementia patients primarily with clinically suspected Alzheimer type disorder. Serum somatomedin values, determined by radioreceptorassay and radioimmunoassay, fell with advancing age in normal subjects. A significant elevation in serum somatomedins was observed in dementia patients. CSF somatomedin levels were also increased in the only two patients with suspected Alzheimer type disease examined. Since somatomedins are believed to act as anabolic hormones, it was suggested that the elevated levels represent a compensatory mechanism to overcome receptor insensitivity in patients with dementia disorders of the Alzheimer type.