Photo credit: http://www.encognitive.com/node/1129
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 10th
edition, Victor P. Eroschenko