1. Non-hormonal/non-neuronal (example: glucose) hormone secretionsare regulated by a substance that is not a hormone nor a nervous system input. Neuronal(example exercise) hormone secretions are regulated by the influence of sensoryinput. Hormonal (example: all releasing) hormone secretions are regulated byanother hormone. 2. Most of the functions of the pituitary gland are regulated bythe hypothalamus.
The hypothalamus and the posterior pituitary gland areconnected by the infundibulum, through which the hypothalamohypophyseal tractruns. Neurons in the hypothalamus connect to the blood supply that connects tothe hypothalamohypophyseal tract to carry secretions meant for the posterior pituitarygland. The hypothalamohypophyseal tractis a collection of axons which carry hormones from the hypothalamus to the posteriorpituitary gland. These hormones are oxytocin and ADH. The hypothalamohypophysealportal system is the blood supply that carries hormones from the hypothalamus tothe anterior pituitary gland. These hormones are inhibiting or releasinghormones called GmRH, TRH, CRH, PrlRH, PrlIH, GHRH, and GHIH.
3. Hydrophobic hormones are built from cholesterol, are able tomove directly into the cell by diffusion, need a transport protein to move inthe blood (example: estrogen) Hydrophilic hormones are soluble in water, madeof proteins, mix easily in the blood. Cannot get past target cell barrier justtouch the surface on a membrane bound receptor (example: oxytocin) 4. Insulin is produced in the pancreas as we consume food and beverages,glucose levels rise causing the pancreas to secrete insulin into the blood.Insulin regulates glucose levels in the blood by communicating with cells inthe blood to absorb glucose. Some cells use that glucose for energy but othercells store the glucose. Glucose stored in the muscles is called glycogen andwhen you haven’t eaten uses this glycogen for fuel. Glucose storage in the liver is calledglycogen.
If glucose levels in the blood become too low the pancreas willrelease glucagon into the blood. Glucagon communicates to the body’s musclesand liver to convert the glucagon back to glucose which is then released backinto the bloodstream. 5. Thyroid – located in the neck below the larynx, makes T3 and T4,functions in metabolism, growth and development, makes calcitonin.Parathyroid–located on top of the thyroid gland, makes parathyroid hormone which increasesblood calcium levelsAdrenal– located on top of the kidneys, adrenal cortex produces steroid hormones suchas aldosterone which allows the body to release potassium and retain sodiumPineal –located deep in the brain, make melatonin which functions in helping the bodyto sleep and controls the circadian rhythm.Thymus-located medial to the lungs, makes thymosin which helps some white blood cellsto mature to become T cells.