GI Secretion Flashcards
what are the three salivary glands
parotid, submandibular, sublingual
how does saliva prevent tooth decay
carries IgA
what cells secrete digestive enzymes such as a-amylase
serous cell with zymogen granules
where do electrolytes move in salivon
sodium and Cl absorbed
K and HCO3- secreted
electrolyte modification primarily takes place in
striated ducts
a fast rate of secretion will have a _____ NaCl content
higher
what are the components of saliva
IgA, muramidase (lysozyme), lactoferrin (quenches iron), thiocyanate ions (destroys bacteria), EGF, NO leukocytes
difference in sympathetic and parasympathetic stimulation of saliva
sympathetic is B adrenergenic, short lived, and more viscous
what are the effects of mineralcorticoids on Na and K
increase na absorption, K secretion
what is the affect does ADH have on of Na reabsoption
increase
how does parasympathetic increase salivation
directly and by increases blood flow
pyloric glands contain what cells
G cells, secrete gastrin
oxyntic glands contain what cells
prietal cells (HCl), endrocrine cells, chief cells
surface mucous cells secrete
mucous and HCO3-
what do D cells produce
somatostatin
what stimulates gastrin secretion
gastrin, ACh, and histamine
what transporter produces HCl in parietal cells
H/K atpase, source is from H2Co3 produced by CA
blood leaving the stomach is
alkaline
what converts pepsinogen to pepsin
HCl
Intrinsic factor is secreted from
parietal cells, necessary for B12 absoprtion at distal ileum
what nuerotransmitters does the vagus nerve use to produce gastric secretion
Ach, histamine
G cells are stimulated by
GRO
parietal cells histamine receptors are blocked by
cimetidine and rantidine
what does somatostatin do
decrease gastrin (acts in duodenum)
what peptide from small intestine and endocrine cells inhibit parietal cells
gastric inhibitory peptide
acid, FA, hyperosmolar chyme in duodenum stimulate
enterogastrones
what enzyme breaks down basic AA
trypsin
what enzyme breaks down aromatic AA
chymotrypsin
where are pancreatic enzymes produced
acinar cells
HCO3 secretion in pancrease is associated with ____ tide in plasma
acid
what increases pancreatic secretion
ACh, secretin, and CCk
secretion from Brunner’s gland (duodenum) is inhibited by
sympathetic tone
secretion from Brunner’s gland (duodenum) consists of
mucous and HCO3-
secretion from Brunner’s gland (duodenum) is stimualted by
irritant, vagus, secretin
sucrase, maltase, isomaltase, lactase are produced by
enterocytes, crypts of lieberkuhn
what are the other functions of the crypts of lieberkuhn
replenishing dead/shed epithelial lining, protect the epithelial cells from damage
what is etiology of cholera toxin
increase cAMP, increase Cl and H2O
what does VIP do
increase small intestine secretion
what is the large intestine response to irritation
excessive water and HCO3 loss
What is the most common cancer of the small intestine
Lymphoma, seen in the peyer’s patches within the lamina propria
What are the most common tumors in the LI
Adenocarcinoma
