The study of the hormonal regulation of our body is carried out by science - endocrinology. In addition, this mechanism of action of all biological compounds is enclosed in such a field of medicine as biochemistry. Both of these sciences are extremely important, since hormones exert many different influences necessary for normal life. It is these substances that are responsible for all types of metabolism in the body (carbohydrate, protein, fat). Thanks to this, the energy distribution of useful substances necessary for maintaining life occurs. One of the most important hormones is insulin. As you know, with its insufficiency, there is a violation of carbohydrate metabolism and the development of diabetes. In addition, counterinsular hormones are no less important. They are also necessary to ensure metabolism. In addition, each of these biological compounds performs its function.
Contrinsular hormone - what is it?
As you know, the hormone insulin is necessary to control glucose levels. If it is excreted in small quantities or is not perceived by receptors, then a person develops diabetes. You should also know that not only a disadvantage is dangerous, but also an excess of this biological substance. To inactivate it in the body, there is a contra-hormonal hormone, and not one, but several. All of them have different effects on carbohydrate metabolism. However, each of them leads to a decrease in the concentration of insulin in the blood. Each of these hormones is produced in the "own" body. The places where these biological substances are produced include the pancreas and thyroid gland, adrenal glands, brain, and testes.
Destination
Contrinsular hormone is a substance that is necessary to ensure carbohydrate metabolism in the body. Its action is aimed at maintaining normal glucose levels. In addition, each counter-hormonal hormone is responsible for its own function, not related to metabolism. Normal blood glucose levels are between 3.3 and 5.5 mmol. If insulin is responsible for ensuring that the sugar concentration does not increase, then its antagonists are necessary to maintain the lower limit of this indicator. With a decrease in glucose in the blood, a condition dangerous to the body occurs - hypoglycemia. It is characterized by a breakdown, decreased blood pressure, tachycardia and tremor. If a person is not helped in time, then hypoglycemia can lead to a coma. To prevent this, hormones that correct the action of insulin are needed. There are several such substances in the body.
Varieties
Contrinsular hormones are biological substances secreted by various endocrine glands. In addition to their own function, each of these compounds is able to regulate carbohydrate metabolism. Nevertheless, in order to maintain normal glycemia, the action of all these substances is necessary. Biological compounds that are insulin antagonists are divided into the following groups:
- Thyroid hormones. Thyroxine belongs to them.
- Substances excreted by the cortical and brain layers of the adrenal glands. Representatives of this group are cortisol and adrenaline.
- Growth hormone. It is secreted in the pituitary gland.
- Contrinsular hormone secreted in the endocrine part of the pancreas. This biological compound is glucagon.
- Testosterone. It is produced both in the cortical substance of the adrenal glands and in the male sex glands - the testes.
Each of these hormones is secreted by its “own” endocrine gland. However, they are all regulated by the hypothalamic-pituitary system located in the brain.
Contrinsular hormones: mechanism of action in the body
Despite the fact that all insulin antagonists affect the metabolism of carbohydrates, their mechanism of action is different. Glucagon has a direct effect on blood glucose levels. This hormone is produced by pancreatic cells constantly. However, if the concentration of sugar in the blood decreases, the secretion of this substance increases. The mechanism of its action is that it affects the liver cells. Due to this, part of the reserve supply of glucose is released and enters the bloodstream. A similar mechanism of action is observed during the development of another contra-hormonal hormone - adrenaline. Glucocorticoids are secreted in the adrenal cortex. With a lack of sugar in the blood, these hormones contribute to its synthesis at the cellular level, that is, lead to the formation of glucose from amino acids. Thyroid hormones increase the effect of adrenaline. Somatotropin exerts a contrinsular effect only in large quantities, more often in childhood (during growth).
The interaction of pancreatic hormones
The pancreas is the main organ of the endocrine system, affecting the metabolism of carbohydrates. It performs both an incretory and secretory function. The anatomically endocrine part of the pancreas is the tail. In it there are such formations as islets of Langerhans. Cells of these anatomical regions are responsible for the secretion of several types of hormones. Some islets secrete insulin. Other cells produce the hormone glucagon. The formation and release into the blood of a substance is affected by glucose levels. A high sugar concentration is a signal for insulin production. Normally, this hormone maintains the glucose level at the proper level, preventing it from rising. The insulin antagonist is glucagon, which, on the contrary, is responsible for the release of sugar into the blood. The coordinated work of pancreatic hormones ensures a normal carbohydrate metabolism in the body. If its secretory function is impaired for any reason, other organs of the endocrine system come to the rescue.
Adrenal gland hormone production
Insulin antagonists are actively produced in the adrenal glands. These organs have 2 layers. Hormones are formed in each of them. In the cortical substance of the adrenal glands, glucocorticoids and androgens have a counterinsular effect. The former contribute to increasing sugar levels in two ways. The representative of this group is the hormone cortisol. It helps increase the number of enzymes needed to convert amino acids to glucose. The next effect of cortisol is the ability to remove “building materials” for sugars from muscle tissue. Thus, this hormone accelerates the process of gluconeonegesis. In addition to cortisol, androgens are produced in the cortical substance. These hormones belong to steroid substances. Their main function is the formation of secondary sexual characteristics. In addition, they affect the metabolism of proteins and carbohydrates. In the cerebral layer of the adrenal glands, a contra-hormonal hormone, adrenaline, is synthesized. When it is released into the blood, an increase in glucose concentration occurs.
Adrenaline: effects on carbohydrate metabolism
The hormone adrenaline is known not only to doctors. Many people know that this substance is released into the blood during severe stress or fear. Indeed, adrenaline is often associated with fear. A typical reaction to the release of this hormone is motor activity, increased heart rate, dilated pupils. Also, this substance is synthesized in laboratory conditions and used in medicine. In addition to the activation of cardiac activity, adrenaline has an effect on carbohydrate metabolism, that is, it has a counterinsular effect. The mechanism of its action is carried out in the following ways:
- It helps accelerate gluconeogenesis.
- Affects the breakdown of glycogen in skeletal muscle. This action of adrenaline is more pronounced.
It is worth noting that in conditions of emotional rest, the hormone does not lead to an increase in the concentration of glucose in the blood. Also, its release does not increase with hyperglycemia. In this, its mechanism of action differs from glucagon. The signal for the release of adrenaline into the blood is emotional arousal, stress.
Testosterone: functions in the body
Testosterone is a contra-hormonal hormone that is produced by the male sex glands. Also, a small amount of this biological steroid is synthesized in the adrenal cortex. The main functions of testosterone are the following effects: an increase in muscle mass, bone growth, activation of sperm and erythropoiesis. In addition, the hormone enhances all metabolic processes in the body, including carbohydrate. According to statistics cited by scientists, men who have high levels of testosterone in the blood are less prone to diabetes and obesity.
Which of the contra-hormonal hormones is stronger?
Definitely it is impossible to answer the question, what is the most powerful contra-hormonal hormone. All of these biological substances affect the increase in glucose in the blood and increase the metabolism of carbohydrates. The action of each of these hormones is opposite to the effect of insulin. However, which substance is the antagonist to a greater extent depends on the concentration of a particular compound. Under normal conditions, glucagon can be called the most powerful hormone. With an increase in thyroid function, thyroxine becomes this substance, with adrenal tumors - cortisol or adrenaline.