Endocrinology Intro

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 Endocrinology is about the study of the hormones produce by the specific organs of our body and it is also study of their function and their diseases. These hormones like growth hormone, oxytocin, estrogens, androgens and prostaglandins are formed  by a specific organ, some of this organs are the Hypothalamus, pituitary gland, adrenal gland, thyroid parathyroid, pancreas, ovaries and testes. These hormones have three characteristics first is that each of this hormones is produce by a specific tissue or gland second is that these hormones are released directly from the tissue into the bloodstream and carried to the site of action and lastly each hormone acts at a specific site or sites to induce certain characteristic biochemical changes.

What happens to the hormones after they were released directly into the bloodstream is that they go or transported to distant target organs. Here, they influence the structure and function of the target organs cells by binding to specific hormone receptors. Where these hormone receptors are can be found? The answer is that hormone receptors can be located on the plasma membrane, cytoplasm or nucleus of the target cells. receptors for protein and peptide hormones usually are located on cell surfaces. Other receptors are intracellular and are used by hormones that diffuse through cellular and nuclear membranes.

Now let us see the different hormones produced by some of the organs in our body first are the hypothalamus. Hypothalamus produced hormones like TRH, CRF, GnRH, the Pituitary gland produced growth hormone, TSH, ACTH, prolactin, oxytocin, vasopressin etc. the adrenal gland produce epinephrine, norepinephrine, cortisol aldosterone etc. the thyroid produce T3, T4, and calcitonin the pancreas produce insulin and  glucagon. Ovaries produce estrogens while the testes produce testosterone and other androgens.

reference:

Clinical Chemistry: A fundamental Textbook, Donald F. Calbreath

Atlas of Histology with functional correlations 10^th edition, Victor P. Eroschenko