Tag: coordination in human beings- chemical control

Secretin is the most important hormone of digestive tract. This hormone stimulates pancreas for synthesis and secretion of non enzymatic part of pancreatic juice. It also stimulates liver for secretion of bile juice and inhibit the gastric acid secretion in stomach and reduce rate of contraction of stomach.

Enterogastrone is a hormone secreted by the duodenal mucosa, when fatty food is in the stomach or small intestine; it is also released, when sugars and proteins are in the intestine. Enterogastrone is transported by the bloodstream to the glands and muscles of the stomach, where it inhibits gastric movements and secretions, by blocking the production or activity of gastrin.

Wm. M. Bayliss and Ernest H. Starling  discovered  secretin, the first hormone, in 1902. They discovered this hormone when they were studying the pancreatic secretion. Secretin hormone stimulates the pancreas to secrete digestive fluid.

Secretin is the most important hormone of digestive tract. This hormone stimulates pancreas for synthesis and secretion of non enzymatic part of pancreatic juice, while pancreozymin promotes the secretion of enzymatic part of the pancreatic juice. Secretin also stimulates liver for secretion of bile juice and inhibit the gastric acid secretion in stomach and reduces rate of contraction of stomach.

Secretin is a peptide hormone produced in the S cells intestinal gland of the duodenum. It inhibits the secretion of gastric acid from the parietal cells of the stomach thereby helps in regulating the pH of duodenum. Hence option A is correct.

Enterogastrone is a hormone secreted by the duodenal mucosa, when fatty food is in the stomach or small intestine. It is also thought to be released, when sugars and proteins are in the intestine. Enterogastrone is transported by the bloodstream to the glands and muscles of the stomach, where it inhibits gastric movements and secretions, possibly by blocking the production or activity of gastrin, the hormone that initially causes these functions. Enterogastrone may slow down stomach emptying by reducing the amount of acid produced. High acid content causes the valve between the stomach and intestine to relax, allowing food passage.

• Cholecystokinin is secreted by cells of the upper small intestine. 
• Its secretion is stimulated by the introduction of hydrochloric acid, amino acids, or fatty acids into the stomach or duodenum. 
• Cholecystokinin stimulates the gallbladder to contract and release stored bile into the intestine. Hence, Cholecystokinin stimulates Gall's bladder.

• VIP in the pituitary helps to regulate prolactin secretion; it stimulates prolactin release in the domestic turkey. Additionally, the growth-hormone-releasing hormone (GH-RH) is a member of the VIP family and stimulates growth hormone secretion in the anterior pituitary gland. Hence, VIP  regulates the secretion of prolactin in turkey.

• In the digestive system, VIP seems to induce smooth muscle relaxation (lower oesophagal sphincter, stomach, gallbladder), stimulate secretion of water into pancreatic juice and bile, and cause inhibition of gastric acid secretion and absorption from the intestinal lumen.
•  Its role in the intestine is to greatly stimulate secretion of water and electrolytes, as well as relaxation of enteric smooth muscle, dilating peripheral blood vessels, stimulating pancreatic bicarbonate secretion, and inhibiting gastrin-stimulated gastric acid secretion. 
•  It also has the function of stimulating pepsinogen secretion by chief cells. VIP seems to be an important neuropeptide during inflammatory bowel diseases.Hence, VIP hormone stimulates the secretion of Pepsinogen.

So, the correct answer is 'Pepsinogen'.