It secretes a namesake polypeptide and produces C-peptide.
Glutamate decarboxylase antibodies are found in many patients with one disease of this organ.  It secretes a namesake polypeptide and produces C-peptide. Like the hypothalamus, its delta cells secrete somatostatin.  This organ's exocrine glands secrete digestive enzymes, but it also has endocrine functions performed by the alpha and beta cells. Those cells in this organ, lying in clusters called the islet of Langerhans, secrete glucagon and insulin. For 10 points, name this organ that regulates blood sugar and whose attack by the immune system leads to type 1 diabetes.
Glutamate decarboxylase antibodies are found in many patients with one disease of this organ.  
pancreas