SST and Alzheimer disease: Somatostatin also plays an important role in the nervous system by regulating the release of neurotransmitters and the excitability of nerve cells and is involved in the regulation of various neural functions.535 In certain neurological disorders such as Alzheimer’s disease abnormalities in somatostatin signaling pathways may affect the progression of the disease and the manifestation of symptoms.536,537 In AD, the reduced expression of SSTR is associated with increased neuronal apoptosis and cognitive decline.