Endocrine system "krīnō", "to separate, distinguish". The human endocrine system consists of several systems that operate via feedback loops. Several important feedback systems are mediated via the hypothalamus and pituitary. Endocrine glands are glands of the endocrine system that secrete their products, hormones, directly into interstitial spaces and then absorbed into blood rather than through a duct. The major glands of the endocrine system include the pineal gland, pituitary gland, pancreas, ovaries, testes, thyroid gland, parathyroid gland, hypothalamus and adrenal glands. The hypothalamus and pituitary gland are neuroendocrine organs. There are many types of cells that comprise the endocrine system and these
Gastric glands the fundus and body of the stomach. They are simple almost straight tubes, two or more of which open into a single duct. "Oxyntic" means acid-secreting and they secrete hydrochloric acid (HCl) and intrinsic factor. The pyloric glands are located in the antrum of the pylorus. They secrete gastrin produced by their G cells. There are millions of gastric pits in the gastric mucosa and their necessary narrowness determines the tubular form of the gastric gland. More than one tube allows for the accommodation of more than one cell type. The form of each gastric gland is similar; they are