Question

How do the hormones secretin, gastrin and CCK affect digestion?

Answer 1

Hormones

1. Hormones are chemical messengers that coordinate many processes in the body.
2. Our endocrine system is made up of several glands, organs, and tissues that produce and release a variety of hormones.
3. The rate at which food passes through the intestines can be impacted by hormonal change or imbalance.

Secretin's role in digestion:

1. Secretin prevents the stomach's parietal cells from releasing gastric acid, helping to maintain the duodenum's pH levels.
2. Bicarbonate production in the ductal cells of the pancreas is induced.
3. This explanation makes it clear that the secretin hormone stimulates the pancreas and is secreted by the S cells of the duodenum.

Gastrin's role in digestion:

1. The parietal cells in the stomach are stimulated to secrete gastric acid by the peptide hormone gastrin, which also promotes gastric motility.
2. It is delivered by G cells in the pancreas, the duodenum, and the pyloric antrum of the stomach.
3. Gastrin causes the pancreas to secrete chemicals and the gallbladder to empty its supply of bile.
4. Meals are more easily digested in the small intestine due to bile and pancreatic secretions.

CCK's role in digestion:

1. This hormone mostly affects how we digest food and how hungry we feel.
2. The pancreatic enzyme and bicarbonate secretion, as well as gallbladder contraction, are stimulated by the cholecystokinin hormone.
3. Exocrine pancreas growth stimulates this hormone, which also reduces gastric emptying (food entry into the intestine by stomach emptying).