What is secreted from the main gastric cells -chief cells, parietal cells and endocrine cell-)?

Chief Cells – Pepsin: a protease that begins the digestion of proteins Parietal Cells – Hydrochloric Acid -HCI-: decreases the pH of chyme for activation and optimum function of pepsin; also though to secrete intrinsic factor Endocrine Cells – Ghrelin: hormone that stimulates the hypothalamus to secrete growth hormone and increase appetite