Question

Please explain gastric/intestinal peptides and hormones.

Answer 1

I assume by gastric/intestinal peptide you mean the enzymes and there is no other interpretation to it.

Proteinases include pepsin,trypsin,chymotrypsin,caroboxypeptides

Pepsin is activated form of pepsinogen which itself is a content of a gastric juice of stomach.It splits proteins into peptones and proteases

Trypsin,chymotrypsin and carboxypeptide are also activated forms of their respective proenzymes.These enzymes are secreted from the exocrine part of the pancreas.Chymotrypsin converts peptones into dipeptides and and carboxypeptide split proteoses into dipeptides.

Intestinal juice includes enterokinase which also helps in the breakdown of protein.

The general substrate of the these enzymes are peptides which finally get coverted to amino acids by their action

Hormones

Gastrin

Secreted by g cells in the pyloric region of the stomach.Stimulates stomach to secrete gastric juice

Enterogastrone

It is secreted by duodenal epithelium.It inhibits gastric secretion

Secretin

Secreted by the epithelium of duodenum releases bicarbonate in the pancreatic juice.It increases the secretion of bile

Duocrinin

Stimulates the brunners gland to release mucus and enzymes into intestinal juice

Pancreatic polypeptide

Inhibits the release of pancreatic juice from the pancreas.