PRACTICAL ROADMAP GLANDS AFFECTING LIFESTYLE WJ van der Spuy & T Tshabalala
GLANDS AFFECTING LIFESTYLE Submandibular gland (salivary gland) Liver Pancreas Hypophysis (pituitary gland) Thyroid Suprarenal (adrenal) glands
SUBMANDIBULAR GLAND Slide 2 Submandibular gland Salivary gland Compound tubulo-alveolar gland Serous (darker staining) and mucous (paler staining) secretory end-pieces
Overview Connective tissue capsule Blood vessel Connective tissue septum dividing gland into lobes Intralobular ducts Interlobular ducts Parenchyma of gland
Lobes and Parenchyma Mucous secretory end-pieces Connective tissue septa Serous secretory end-pieces Interlobular ducts Blood vessel Adipose tissue Intralobular ducts (striated) Lobe Parenchyma - cells and ducts
Secretory Units Serous secretory end-pieces with spherical basal nuclei Serous demilunes Interlobular duct Mucous secretory end-pieces with flattened basal nuclei Blood vessel Adipose tissue Myoepithelial cell Intralobular duct
Ducts Blood vessel Intercalated duct - Intralobular - Lined by cuboidal epithelium Interlobular duct - Lined by stratified epithelium - Surrounded by connective tissue Striated duct - Intralobular - Lined by columnar epithelium
Striated Ducts Striations of intralobular ducts Myoepithelial cell Zymogen granules in apical cytoplasm of serous secretory cells
LIVER Slide 23 Liver H&E stain
Overview Liver parenchyma - hepatocytes (cells) - sinusoids (capillaries) Connective tissue capsule - sends septa into parenchyma Portal tract
Structures of Note Liver parenchyma - hepatocytes (eosinophilic) - sinusoids (white spaces) Connective tissue capsule Portal tract - surrounded by connective tissue Connective tissue septum Central vein
Portal Tract Branch of hepatic artery Branch of portal vein Branch of bile duct Portal tract Note: Artery & vein lined by endothelium Bile duct lined by simple cuboidal epithelium
Classical Liver Lobule Classical liver lobule - roughly hexagonal shape - central vein at midpoint - sinusoids draining into central vein - portal tracts at corners of hexagon Central vein Cords of Hepatocytes (pink) & Sinusoids (white spaces) radiating towards central vein
Blood & Bile Flow Portal tract Central vein
Haemosiderin (yellow-brown particles) Liver Parenchyma Endothelial cell Hepatocyte Sinusoid lined with endothelium & Kupffer cells Kupffer cell (stellate shape) Endothelial cell Bi-nucleated Hepatocyte
PANCREAS Slide 17 Pancreas H&E stain
Overview Connective tissue capsule Parenchyma of exocrine pancreas (dark staining) Blood vessel Interlobular duct Connective tissue septum dividing gland into lobes & lobules Islets of Langerhans - endocrine pancreas (pale staining)
Endocrine vs Exocrine Exocrine pancreas Endocrine pancreas Islet of Langerhans - cells arranged in short, irregular cords separated by fenestrated capillaries Acini - cells arranged around an intercalated duct
Endocrine Cell Types Insulin-secreting B cells 70% of Islet Glucagon-secreting A cells 15-20% of Islet Micrographs TN Augustine MSc
Exocrine Cell Types Acinus Pancreatic acinar cell Basophilic basal cytoplasm of pancreatic acinar cell Centro-acinar cell - pale-staining nucleus Eosinophilic apical cytoplasm of pancreatic acinar cell
Intercalated Duct Acinus Acinus Intercalated duct Acinus
Intralobular Duct Acinus Acinus Intralobular duct
HYPOPHYSIS Slide 94 Hypophysis (Pituitary gland) Mallory stain Acid fuchsin (nuclei of secretory cells stain red) Aniline blue (collagen & colloid stains blue) Orange G (erythrocytes & nucleoli stain orange/red)
Pituitary Gland Two functional units - Adenohypophysis - Pars tuberalis - Pars distalis - Pars intermedia - Neurohypophysis - Pars nervosa - Infundibulum
Overview Pars tuberalis Infundibular stem Connective tissue capsule Pars distalis Pars intermedia Pars nervosa
Overview Pars tuberalis Pars intermedia Connective tissue capsule Pars distalis Infundibular stem Pars nervosa
Functional Areas Pars distalis - red and blue stained Pars nervosa -palely stained Pars intermedia - blue stained
Pars Distalis Collagen Dilated cappilary containing erythrocytes Chromophobes (unstained) Basophils (blue-stained) Acidophils (red-stained)
Pars Intermedia & Nervosa Pars intermedia Pars nervosa Colloid - blue & orange stained Collagen Basophil Blood vessel filled with erythrocytes
Pars Nervosa Blood vessels Collagen Herring body Erythrocytes Blood vessel
Pars Nervosa Erythrocytes Pituicytes Fibroblast Note: Mast cells are also present in Pars Nervosa though not shown in micrograph
Infundibulum Pars distalis Pars tuberalis Infundibulum
Pars Tuberalis Blood vessels Pars tuberalis (highly vascular) Infundibulum
THYROID GLAND Slide 44 Thyroid H&E stain
Overview Connective tissue capsule Blood vessel Connective tissue capsule Connective tissue septa forming lobules Follicles filled with colloid
Connective Tissue Connective tissue capsule Connective tissue septa dividing gland into lobules
Follicles Connective tissue septa Thyroid follicle (functional unit) Simple cuboidal follicular cells Follicle Colloid
Parafollicular Cells Parafollicular cells - found within the follicle in the simple cuboidal epithelium - and between follicles
SUPRARENAL GLAND Slide 92 Suprarenal H&E stain
Overview Connective tissue capsule Cortex - 3 zones Medulla - highly vascular
Regions and Zones Connective tissue capsule Cortex Zona fasciculata Zona reticularis Medulla Zona glomerulosa
Zona Glomerulosa Connective tissue capsule Zona glomerulosa - parenchyma arranged in ovoid clusters)
Zona Fasciculata Zona fasciculata - long straight chords separated by fenestrated capillaries Capillary
Zona Reticularis Zona reticularis - parenchyma arranged in anastamosing chords)
Medulla Blood vessels Chromaffin cells