Lecture 2 – Tubular GI Histology of the Esophagus, Stomach and Intestines Dr. Pillinger Lecture on Friday, 8/3/2012

Lecture Material Only

1a. What is this layer 1b. What does this layer include (three things) 2. What is this layer 3a. What is this layer 3b. What does this layer include (two things) 4. What is this layer General Structure of the Digestive tract

LP = lamina propria MM = muscularis mucosae MP = muscularis externa SM = submucosa: PG = parasympatheti c ganglion Components of Wall of GI Tract Meissner submucosal plexus Auerbach myenteric nerve plexus

Components of Wall of GI Tract Auerbach’s myenteric plexus CM = circular layer of smooth muscle LM = longitudinal layer of smooth mus cle

Histology of Esophagus Lamina propria with papilla Muscularis mucosa mucosa Squamous epithelium submucosa Lymphoid follicle in submucosa Inner circular muscle Connective tissue Outer longitudinal muscle muscularis

Histology of Esophagus

Normal esophageal mucosa 1 2 Epithelium of Non-keratinizing stratified squamous mucosa lamina propria coming into epithelium (papilla formation

Esophagus (cross sections) 3? 2? 4? 5? 6? 7? 1 – name boxes Top to bottom

CM = inner circular layer of muscularis propria E = epithelium G = seromucous gland LM = outer longitudinal layer of muscularis propria LP = lamina propria Ly = lymphoid aggregates MM = muscularis mucosae MP = muscularis propria SM = submucosa Esophagus (Masson's trichrome )

Normal GE junctions pylorus Rugae Type of epithelium? Squamous Type of epithelium? Columnar

Semi-aligned drawing & micrograph of gastric glands

C = circular layer of muscularis externa GP = gastric pits L = longitudinal layer of muscularis externa M = mucosa MM = muscularis mucosa O = oblique layer of muscularis externa Body of the stomach

Base of gastric gland E = enteroendocrine cell Pc = chief cells PI = parietal cells

Stomach: Pyloric area Immunostain for Gastrin MM = muscularis mucosa G = gastrin secreting enteroendocrin e cells P = gastric pit s

B = Brunner glands CM = circular layer of muscularis D = duodenum LM = longitudinal layer of muscularis PS = pyloric sphincter S = stomach Gastroduodenal junction (pylorus)

Normal small bowel Submucosal glands Muscularis mucosa submucosa Dilated blood vessel Lymphatic vessels Inner layer of circular muscularis Outer layer of longitudinal muscularis Auerbach’s myenteric plexus would be here

B = Brunner's submucosal glands CM = inner circular layer of muscularis LM = longitudinal layer of muscularis M = mucosa MM = muscularis mucosa SM = submucosa V = villi Monkey duodenum © Elsevier. Young et al. Wheater’s Functional Histology 5e –

Normal small bowel: histology villi Crypts Inflammatory Cells Lamina propria Muscularis mucosa Submucosa Goblet cells Nuclei

Intestine:Crypts of Lieberkuhn G = goblet cell Mt = mitotic figure P = Paneth cell E = enteroendocrine cell

B = Brunner's glands CM = inner circular layer of muscularis LM = longitudinal layer of muscularis M = mucosa MM = muscularis mucosa PC = plicae circularis SM = submucosa Sr = serosa V = villi C = crypts of Lieberkuhn LP = lamina propria What layer of the GI tract is this? Duodenum Ileum

B = Brunner's glands CM = inner circular layer of muscularis LM = longitudinal layer of muscularis M = mucosa MM = muscularis mucosa PC = plicae circularis SM = submucosa Sr = serosa V = villi C = crypts of Lieberkuhn LP = lamina propria Intestinal villi & crypts What is this?

C = capillary L = lacteal Ly = lymphocytes Mu = smooth muscle fiber Intestinal villi (a) H&E (b) PAS/iron H/orange G (c) H&E Mitosis

M = muscularis externa P = plica circulares S = serosa SM = submuscosa V = villi Folding of small intestine Slide 24 Fold, plica circulares

Ileum with Peyer’s patches What area of the GI tract is this?

S = serosa M = mesentery F = follicle LP = lamina propria Normal appendix

CM = circular layer of muscularis LM = longitudinal layer of muscularis LA = lymphatic nodule Colon Goblet cells fat submucosa

Recto-anal junction J = line of Hilton RM = rectal mucosa SS = skin