Histology Glands

BY Dr Navneet Kumar Professor Anatomy KGMU LKO

Dr Navneet Kumar Professor Anatomy KGMU LKO Glands

– a single cell or a mass of epithelial cells adapted for secretion – derived from epithelial cells that sank below the surface during development

Dr Navneet Kumar Professor Anatomy KGMU LKO Glands…..classification

• Basis on site of secretion • Endocrine glands • Exocrine glands • Paracrine glands

Dr Navneet Kumar Professor Anatomy KGMU LKO Glands ….classification • Basis on mode of secretion • 1. Merocrine gland. – By cytoextosis no loss of cytoplasm e.g. most of exocrine glands

• 2. Apocrine gland - partial loss of cytoplasm e.g. mammary glands, sweat glands

• 3. Holocrine glands- total loss of cell e.g. sebaceous glands, tarsal glands

• 4. Cytocrine glands- cells as secretion e.g. testis

Dr Navneet Kumar Professor Anatomy KGMU LKO

Dr Navneet Kumar Professor Anatomy KGMU LKO Glands…. classification

Basis on shape and ducts • Simple duct gland - Acinar or Alveolar Straight e.g urethral gland Branched e.g sebaceous gland - Tubular Straight e.g. intestinal glands. Branched e.g. uterine glands pyloric and fundic part of stomach, Coiled e.g. sweat gland • Compound duct gland Tubular e.g cardiac part of stomach, Acinar e.g parotid gland, Tublouacinar gland e.g submandibular gland Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Organ associated with G.I.T.

• Salivary glands -Parotid gland -Sub mandibular gland -Sub lingual gland • Pancreas • Liver • Gall bladder

Dr Navneet Kumar Professor Anatomy KGMU LKO Salivary glands

Serous salivary gland

Mucus salivary gland

Mixed salivary gland

Dr Navneet Kumar Professor Anatomy KGMU LKO Salivary glands……

Serous salivary gland Serous Acini- -Large Round central nucleus, -Boundary indistinct Small lumen -Darkly stained, Zymogen granule - Thin Watery secretion

Dr Navneet Kumar Professor Anatomy KGMU LKO Salivary glands…..

Mucus salivary gland Mucus Acini -flat, peripheral nucleus -Boundary distinct, Large lumen -Lightly stained mucigen droplets - Viscous secretion

Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Salivary gland

Dr Navneet Kumar Professor Anatomy KGMU LKO Salivary glands……..

Mixed salivary gland • -Both mucus and serous acini • myo epithelial cells • -Demilunes

Dr Navneet Kumar Professor Anatomy KGMU LKO Salivary gland- Demilunes and Ducts

Demilunes- mucus acinus covered with serous cells Ducts- Acinus (alveolus) opens in -Intercalated ducts - cuboidal cells -Striated ducts columnar cells with striations Excretory duct- columnar cells

Dr Navneet Kumar Professor Anatomy KGMU LKO Parotid Salivary gland

• Mostly compound serous acini • Large number of ducts • Adipocytes and plasma cells

Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Parotid salivary gland

Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Sublingual salivary gland

Predominantly mucus acini (compound tubuloacinar) - Demilunes may present - Few ducts

Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Sub mandibular gland

• -Both mucus (few) and serous acini (more) present • myo epithelial cells • -Demilunes

Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Sub mandibular gland

Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Pancreas Exocrine and endocrine parts Exocrine glands- -Serous acini present -Acini are compact ,less lumen -Acini secrete digestive enzyme -Centroacinar cells continue as intercalated ducts, secrete alkaline fluid Endocrine glands- -Island of langerhans -branching cords like pattern of pale staining cells Dr Navneet Kumar Professor Anatomy KGMU LKO Pancreas …..

• Endocrine cells 1.Alpha cells-20%,mainly at periphery, large cells secrete glucagon 2.Beta cells-70%,at centre, small cells, secrete insulin 3.Delta cells-5%, secrete somatostatin 4.F cells-secrete polypeptides

Dr Navneet Kumar Professor Anatomy KGMU LKO Pancreas

Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Liver

• Histological structure

• Connective tissue -Glisson capsule -trabeculae

• Parenchyma -Liver lobule (hepatic lobule)

Dr Navneet Kumar Professor Anatomy KGMU LKO Liver Glisson capsule- trabeculae Portal tract-portal triad -1.Portal venule,2. bile ductule3. hepatic arteriole -Space of mall

Dr Navneet Kumar Professor Anatomy KGMU LKO Liver

Hepatic lobule- -hexagonal shaped -Central vein -Heptocytes -Hepatic plates

Dr Navneet Kumar Professor Anatomy KGMU LKO Liver …….Hepatic lobule-

-Liver sinusoids -Kuffer cells -Space of Disse -Bile canaliculi

Dr Navneet Kumar Professor Anatomy KGMU LKO Portal lobule and Hepatic acini

Portal tract • Portal lobule- area Central vein drain by bile duct (functional )

• Hepatic acinus- blood supply area by hepatic artery

Portal lobule Hepatic acinus

Dr Navneet Kumar Professor Anatomy KGMU LKO Hepatic acinus

Portal lobule

Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Gall bladder

1.Mucosa- • Epithelium-simple columnar with micro villi • Lamina propria • Mucosal folds • Muscularis mucosae and sub mucosa absent 2.Fibro muscular layer 3.Serosa/Adventitia

Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Gall bladder Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Dr Navneet Kumar Professor Anatomy KGMU LKO Gall bladder Dr Navneet Kumar Professor Anatomy KGMU LKO