Somatostatin and vasoactive intestinal polypeptide in postmortem brains from patients with Alzheimer-type dementia

Somatostatin- and vasoactive intestinal polypeptide (VIP)-like immunoreactivities (SLI and VLI, respectively) were measured, by radioimmunoassay, in 21 regions of postmortem brains from 7 histologically verified cases of patients with Alzheimer-type dementia (ATD) and 10 histologically normal controls. SLI was significantly reduced in the orbital cortex, hippocampus and putamen of ATD brains. Significant reduction of VLI in the ATD brains was also found in the insular and angulate cortex, which have not previously been examined biochemically for peptides. These results suggest that involvement of not only somotostatin- but also VIP-containing neurons may not be ruled out in ATD brains.