Gastric Physiology
Physiology of stomach:-
For understanding approaches for gastro retention, it is essential to overview gastric physiology and gastric motility. The stomach is situated in the left upper part of the abdominal cavity immediately under the diaphragm. Human stomach has a resting volume of 25-50ml, which can distend upto1500ml following a meal. It is divided into 5 anatomical parts:
a) Cardia:- First part of the stomach below the esophagus. It contains cardiac spincter,which is a thin ring of muscle that prevents stomach contents from going back to esophagus.
b) Fundus: also called proximal stomach, it is present left to the cardia which acts as food reservoir.
c) Body:- It is the largest and main part of the stomach. This is where food is mixed and starts to break down.
d) Pyloric part : divisible into 3 regions:- …show more content…
Pyloric antrum:- connects to the body of stomach.
2. Pyloric Canal :- leads to the third region, pylorus.
3. Pylorus: It inturn connects to the duodenum.
Pylorus also called distal stomach, part of the stomach that connects to the small intestine. It acts as a site of mixing motions to propel gastric contents for emptying.This region includes pyloric spincter, which is a thick ring of muscle that acts as a valve to control stomach contents empty into duodenum. Pyloric spincter also performs the function of preventing contents of duodenum from going back to stomach.
Gastric motility is also a key factor in stomach specific drug delivery. Brief knowledge of motility is necessary for developing a retentive form of drug.
Gastric motility differs in fasting and fed states.
In fasting states, an Inter-digestive myoelectric motor complex (IMMC), a 2 hr. cycle of peristalsis is generated which progresses to ileocecal junction. It consists of 4 phases:
a) Phase I: also called quiescent period with rare low amplitude contractions, lasting for 30-60 mins. b) Phase II: It consist of intermediate amplitude contractions with bile secretions. It lasts
For understanding approaches for gastro retention, it is essential to overview gastric physiology and gastric motility. The stomach is situated in the left upper part of the abdominal cavity immediately under the diaphragm. Human stomach has a resting volume of 25-50ml, which can distend upto1500ml following a meal. It is divided into 5 anatomical parts:
a) Cardia:- First part of the stomach below the esophagus. It contains cardiac spincter,which is a thin ring of muscle that prevents stomach contents from going back to esophagus.
b) Fundus: also called proximal stomach, it is present left to the cardia which acts as food reservoir.
c) Body:- It is the largest and main part of the stomach. This is where food is mixed and starts to break down.
d) Pyloric part : divisible into 3 regions:- …show more content…
Pyloric antrum:- connects to the body of stomach.
2. Pyloric Canal :- leads to the third region, pylorus.
3. Pylorus: It inturn connects to the duodenum.
Pylorus also called distal stomach, part of the stomach that connects to the small intestine. It acts as a site of mixing motions to propel gastric contents for emptying.This region includes pyloric spincter, which is a thick ring of muscle that acts as a valve to control stomach contents empty into duodenum. Pyloric spincter also performs the function of preventing contents of duodenum from going back to stomach.
Gastric motility is also a key factor in stomach specific drug delivery. Brief knowledge of motility is necessary for developing a retentive form of drug.
Gastric motility differs in fasting and fed states.
In fasting states, an Inter-digestive myoelectric motor complex (IMMC), a 2 hr. cycle of peristalsis is generated which progresses to ileocecal junction. It consists of 4 phases:
a) Phase I: also called quiescent period with rare low amplitude contractions, lasting for 30-60 mins. b) Phase II: It consist of intermediate amplitude contractions with bile secretions. It lasts