regulation functions that support the livelihoods of the human body, is achieved in two fundamentally different ways.First - a humoral control mechanism that is earlier when measured functional and structural elements of the human body in terms of phylogenetic development.The second mechanism is much more flexible and more responsive to changes in the state of the body.This nervous regulation, the essence of which is reduced to the correction functions involving visceral and peripheral reflexes, while the effect of the humoral factor is the interaction with the mediator molecule receptor complex cell to target organs.When this transmission signal is conducted by means of biological molecules, the synthesis of which are present in the body of the endocrine glands.They secrete substances that can spread through the bloodstream to a certain distance from the gland and influence controlled bodies.
Endocrine gland: the structure of humoral regulation
responsibility for the proper functioning of all systems and organs carries the brain, which is the highest center of analysis of incoming information, and the site of synthesis of the signals sent by the target cells above two systems.And if the nervous influence is through the many links on a dedicated type of fabric, the humoral aposredstvenno implemented by transport of bioactive molecules that can activate the receptor complexes on the cells of target organs.Thus the endocrine glands are arranged in a special way, and this is fundamentally different from the exocrine.Firstly, exocrine glands secrete their molecule outward i.e. the external environment.It requires special excretory ducts, which do not have the endocrine glands, secretory cells that resets the hormones directly into the bloodstream.
It is important that the highest center of humoral regulation is in the brain, namely the hypothalamus.His glandular tissue of neural origin synthesizes statins, inhibits the synthesis of pituitary hormones, and liberiny that contrary to modulate its function.Through this bidirectional influence achieved control of all functions of the endocrine glands of the body.At the same time another center of hormonal regulation of pituitary function is - the structure is about 20 times smaller than the hypothalamus, but performs much needed function.It is also noteworthy that such a small gland performs synthesis of high-molecular compounds in large quantities, which are called hormones, while superior structure produces only statin with liberinami that very simple chemical structure, as are the dipeptide.
rest of the endocrine glands are controlled by the pituitary gland and is simply the cycle of secretion is dependent on the activity of the synthesis of tropic hormones.This neurohypophysis are synthesized also ADH, which regulates the reabsorption of water molecules in the collecting ducts of nephrons of the kidneys, and oxytocin, responsible for uterine contractions during labor and milk secretion of mammary glands.Adenohypophysis or anterior lobe of the prostate, controls growth processes of the body, the cycle of secretion of thyroid hormones, decarboxylation in the adrenal medulla, the synthesis of steroid hormones in the adrenal cortex.
very important organs for humans is the pancreas and gonads.According to its structure and function - a cancer with mixed secretion, ie they have a body sites, some of which have the type of endocrine glands, and the second - eccrine.So sex glands secrete sex cells into the environment, but the hormones go directly into the bloodstream.Thus endocrine function of the pancreas to synthesize reduces glucagon, insulin and somatostatin, exocrine - a synthesis amylases and peptidases for digestion in 12 duodenum.Because the pancreas, exactly like the gonads - is exocrine and endocrine gland at the same time.
