MODULE 7.2 HORMONES OF THE GI TRACT

Question 1

“LITTLE GASTRIN”
(form of gastrin)

Answer 1

G cells in the antrum of the stomach are the primary source, which is secreted in response to both luminal and basolateral stimuli.

Question 2

“BIG GASTRIN”
(form of gastrin)

Answer 2

G cells in the duodenum are the primary source, its not as potent as little gastrin at stimulating stomach acid secretion, it has a longer half-life in the blood.

Question 3

HYPERPLASIA

Answer 3

increase in organ size due to an increase in the reproduction rate of cells.

Question 4

HYPERTROPHY

Answer 4

an increase in organ size due to an increase in the size of each cell.

Question 5

What are the 4 criteria’s that must be met demonstrate conclusively that a substance acts as a hormone in the GIT?

Answer 5

1. PHYSIOLOGICAL EVEN IN ONE PART ALTERS ACTIVITY IN ANOTHER
2. EFFECT PERSISTS AFTER DENERVATION (all neural connections between the two parts are severed, after denervation)
3. ELIMINATING SOURCE TISSUE PREVENTS RESPONSE (prevent the response of the target tissue)
4. ISOLATED SUBSTANCE PRODUCES RESPONSE WHEN INJECTED INTO BLOOD AT PROPER DOSE.