In addition to secreting hormones, the endocrine organs (stomach, duodenum, and pancreas) and the gonads (germ glands) serve additional crucial roles. These are multifunctional organs that are crucial parts of other systems as well as the endocrine system. The pituitary, thyroid, parathyroid, and adrenal glands, on the other hand, are endocrine glands whose sole known function is to secrete hormones.
The two adrenal glands are situated quite close to the kidneys, as implied by their names, which translate to “there” and “renal kidney.” Each adrenal gland in a mammal is actually a pair of glands. It is made up of an inner, medulla-like core and an outer, cortex-like shell. The medulla and cortex have unrelated activities and come from different embryonic tissues. Even as adults, fish and amphibians retain two distinct sets of glands. Although the two glands have developed a spatial relationship in reptiles, birds, and mammals (in reptiles and birds, the tissues of these two glands are interlaced rather than forming a distinct cortex and medulla, as in many mammals), their functional differences have not changed. Endocrine Medulla
Adrenaline, often known as epinephrine, and noradrenaline are both secreted by the adrenal medulla (norepinephrine). Though comparable, their roles are not identical. Both hormones have been isolated, recognized, and laboratory-created.
It has been demonstrated to have a wide range of physiological effects. As an illustration, adrenaline raises blood pressure, heart rate, glucose transport from the liver to the circulation, oxygen consumption, and the flow of extra erythrocytes from the spleen into the blood. It also increases the conversion of glycogen to glucose. It produces vasoconstriction (vasodilation) and decreased blood flow in the smooth muscles of the skin and digestive tract, as well as the erection of hair and hair follicles and the dilating of pupils. It also causes vasodilation (vasodilation) and increased blood flow in skeletal and cardiac muscle.
At first look, this list would seem to include factors that have no apparent relationship to one another, but upon closer inspection, it becomes clear that these reactions all take place in response to strong physical effort, pain, fear, rage, and other evoked mental states. These are occasionally referred to as “fight-or-flight” reactions. Adrenaline (and, to a lesser extent, noradrenaline) after each fast neuronal stimulation helps to maintain them, however these are actually primarily initiated by the neurological system. These hormones aid the body in mobilizing its resources in times of crisis. They do this by inducing processes that boost the flow of glucose and oxygen to the skeletal and cardiac muscles through the blood. Additionally, they prevent processes like digestion from taking place in an emergency that would otherwise compete with the skeletal muscles for oxygen.
Probably the most significant physiological action of adrenaline is that of an insulin antagonist, which stimulates the liver to produce glucose from glycogen stores, boosting blood sugar and promoting the conversion of muscle glycogen to lactic acid. This travels through the blood to the liver where it is changed into glucose. Endocrine System
The absence of adrenal cortices results in death because they are necessary for life. The body’s fluids’ terrible ionic equilibrium, impaired carbohydrate metabolism, which causes a considerable drop in blood glucose levels and storage glycogen, weight loss, generalized muscle weakness, and an odd browning of the skin are all symptoms that occur before death. In varied degrees, these symptoms are also present in people with Addison’s disease, a disorder in which the adrenal cortices are underactive.
These numerous signs of adrenal cortical insufficiency are not all caused by any one hormone. The adrenal cortex is a remarkable endocrine factory, no doubt about it. Scientists are still unsure of the exact number of hormones it generates since they are so many and diverse.
Chemically, all cortical hormones are similar. They are all steroids that are created by altering cholesterol, a material found in membranes. Many are only one or two atoms apart from one another. The various hormones nevertheless work in remarkably varied ways as a result of these ostensibly subtle variations.
They alter many chemical reaction pathways by binding to diverse receptors on target cells. Notably, these hormones differ chemically from one another. Steroid hormones are only found in mammals in the adrenal cortex, gonads, and other reproductive organs.
As far as we are aware, the hormones produced by other endocrine organs are entire proteins, short polypeptide chains, or amino acids (or their derivatives, such as adrenaline and noradrenaline) (like insulin). These cortical steroids, which play a significant role in vertebrates, are divided into groups based on what they do. A good adaption is to be fit and active. Natural selection would therefore be in favor of the body’s capacity to generate a hormone that fights sickness and does so without having any negative side effects. Such a hormone has not yet been identified.
Since they alter the collagen fibers in these tissues visibly, cortisone and compounds similar to it are currently most frequently employed to speed up healing or only partially cure the symptoms of arthritis and other connective tissue illnesses. They are occasionally used to treat severe allergic illnesses, including asthma and some forms of lymphatic diseases. Some skin rashes are also alleviated by cortisone when applied topically. They are also employed in crises to provide momentary respite from severe symptoms. Physicians prefer to give doses that alleviate the patient’s symptoms rather than enough medication to totally eliminate them because they have to take into account any severe side effects. The conundrum surrounding cortical hormones serves as an example of a general issue that doctors encounter every day. Numerous medications, as well as other types of treatment, might have negative side effects. Therefore, doctors must always weigh the potential benefits against the potential drawbacks and keep in mind that even the safest medications can be harmful if used excessively or inappropriately. The interactions between the body’s various components are so intricate and well-tuned that they still largely defy understanding. When using chemicals, there is a chance of causing damage to the equipment because they almost always have unanticipated effects on very distinct operations.