endocrine systen

• The endocrine system consists of organs that will secrete hormones or enzymes directly into the blood/lymph system
• Examples of endocrine glands include pituitary gland, thyroid gland, parathyroid gland, adrenal gland, pancreas, ovaries (female), testes (males)
• The function of the endocrine system is stimulate or inhibited depending on feedback signaling
• The hormonal system works in a continual and slow process, with the hormones being released and then being taken up by the target cells
• Sometimes, endocrine cells are found in non-endocrine organs, such as the pancreas.
• the pituitary gland
• the pineal body is a gland that produces melatonin, a hormone that regulates sleep and wake cycles
• The pituitary gland releases hormones that stimulate other organs to secrete hormones
• rathke's pouch detaches from the stomadeum and attaches to the diencephalon to become adenohypophysis and neurohypophysis that is still separated by connective tissue

  
• adenohypophysis secretes growth hormone, thyroid-stimulating hormone, follicle-stimulating hormone, luteinizing hormone, prolactin, and antidiuretic hormone
• adenohypophysis: is 40% eosinophils and 10% basophils
• neurohypophysis contains nerve fibers and axons that extend from the hypothalamus
• the secretion of melanin is regulated by the pars intermedia
• neurohypophysis: the posterior lobe of the hypophysis (pituitary gland), which stores and releases oxytocin and vasopressin produced in the hypothalamus.
• herring bodies: vesicle-storing hormones
• the pineal gland contains pinealocytes, glial cells, neuropil, and corpora arencea (brain sand)
• corpora arenacea are calcified deposits of calcium carbonate
• thyroid gland: produces thyroxine, regulates metabolism
• parathyroid glands: produce parathormone, regulate blood Ca2+ levels
• adrenal gland: produces adrenaline and cortisol
• the adrenal gland is positioned above the kidneys in humans
• the adrenal medulla secretes catecholamines such as epinephrine and norepinephrine
• the adrenal cortex secretes steroid hormones including aldosterone, corticosteroids, and sex hormones
• glucagon: a hormone formed in the pancreas which promotes the breakdown of glycogen to glucose in the liver.
• insulin: a hormone produced in the pancreas by the islets of Langerhans, which regulates the amount of glucose in the blood. The lack of insulin causes a form of diabetes.
• other endocrine cells include: adipocytes (leptin), enteroendocrine cells(ghrelin, somatostatin), some heart cells (ANP) juxtaglomerular cells of the kidney (renin)
• adipocyte: fat cell that stores lipids and releases them when needed; also produces leptin
• enteroendocrine cells: specialized cells found throughout the GI tract that produce various hormones involved in digestion and metabolism, including gastrin, secretin, cholecystokinin, motilin, and serotonin
• juxtaglomerular cells: specialized cells located near the glomeruli in the kidney that release renin into the bloodstream in response to changes in blood pressure or volume