Has exocrine endocrine functions Parts Capsule Septa lobules

� Has exocrine & endocrine functions � Parts � Capsule � Septa – lobules � Secretions: � Enzymes � Hormones

� COMPOUND ACCINAR GLAND � Pear shaped accini � 5 -8 pyramidal cells � Reticular fibers support accini � Inter- lobular CT contains: � Blood vessels � Nerves � Lymphatic

� ACCINI � Cells have spherical basal nucleus � Basal cytoplasm basophilic – RER � mitochondria � Golgi apparatus � Apical zymogen granules – maximum in fasted person � Centroacinar cells

� DUCTS � Intercalated ducts � NO striated ducts � Large intralobular ducts – high cuboidal epithelium � Interlobular ducts – columnar epithelium � Larger ducts � Main duct

� SECRETIONS OF EXOCRINE PANCREAS � Proteases (trypsinogen & chymotrypsinogen etc. ) � Amylase � Lipase � Nucleases (DNAase & RNAase)

� ACUTE NECROTIZING PANCREATITIS � Proenzyme activated � Digest pancreatic tissue � Causes: � Alcoholism � Gall stones � Trauma � Drugs

� Extreme malnutrition e. g. kwashiorkor � Atrophy of pancreatic acinar cells � Loss of RER � Digestive enzyme production hindered

� Embedded within accini � 100 -200µm diameter � > 1 million islets � Abundant in tail

� Reticular fibers surround each islet � Small polygonal cells � Cells lightly stained � Arranged in anastomosing cords � Fenestrated capillaries between cords � Autonomic fibers

� CELLS OF ISLETS � A /α cells- glucagon, at periphery � B /β cells- insulin, at centernumerous � D /δ cells- somatostatin, scattered � F /PP cells- pancreatic polypeptide � Enterochromaffin cellsmotilin, secretin, substane -P

� Rich arterial supply � Major BV run in interlobular CT � Intralobular BV � Arterioles pass to islets � Extensive capillary network � First supply peripheral cells � Blood from islets pass to supply exocrine tissue � Hormones effect acinar function

� PANCREAS � PAROTID GLAND

� � � INSULIN DEPENDENT / TYPE I DIABETES (juvenile) Autoimmune disease Partial or total destruction of β cells Lack of insulin INSULIN INDEPENDENT DIABETES / TYPE II Adult onset Associated with obesity Failure of cell to respond to insulin TUMOURS OF ISLETS May secrete anyone of the hormones May secrete more than one hormone