- Allergy treatment
- Antimicrobials for systemic use
- Antiparasitic drugs
- Cardiovascular system
- Dermatology
- Drugs affecting metabolism
- Drugs used in sensory organ disorders
- Gastrointestinal tract
- Haemopoietic system and blood
- Locomotor system
- Nervous system
- Respiratory system
- Systemic hormones
- Urogenital system and Sexual hormones
Systemic hormones
- Hormone and Endocrine system overview
- Hormones of anterior pituitary and Neurohormones
- Thyroid and parathyroid hormone
- Adrenal glands
- Sexual hormones
- Gastrointestinal hormones
Hormones are organic compounds produced by certain cells and are intended to control the functions of organism, its regulation and coordination. Higher animals have two regulatory systems by which the body adapts to the constant internal and external changes. One of them is nervous system that quickly transmit the signals (in the form of impulses) through a network of nerves and nerve cells, the other is endocrine system performing chemical regulation though the production of hormones, which are carried by the blood and exert an effect on target tissues and organs. Hormonal system is closely related to nervous system. Some hormones act as mediators between the nervous system and innervating organs. Thus, the difference between the nervous and chemical regulation is not absolute.
The physiological effects of hormones are focused on:
- providing humoral regulation of biological processes,
- maintaining the integrity and constancy of internal environment, appropriate interaction between the cellular components of the body
- the regulation of growth, maturation and reproduction.
Hormones regulate the activity of all body cells. They affect the mental sharpness and physical mobility, constitution and height, determine the growth of hair, voice tone, sexual excitement and behavior.
Endocrine system help organism adapt to significant temperature changes, physical and emotional stress. Study of the physiological effect of the endocrine system allowed to disclose the secrets of sexual function and the miracle of birth, as well as to answer the question why some people are tall and some low, some slow but other are nimble, some strong and others are weak.
In a healthy organism there is a harmonious balance between the activity of the endocrine glands, the condition of the nervous system and the response of target tissues (tissues that are exposed to hormonal action). Any disorder in each of these system quickly leads to deviations from the norm. Excessive or insufficient production of hormones is the cause of various diseases associated with extensive chemical changes in the organism.
According to the classical definition, hormones are products of endocrine glands secretion, released directly into the bloodstream and possessing high physiological activity. The main endocrine glands that produce hormones are pituitary gland, thyroid and parathyroid glands, adrenal cortex, adrenal medulla, pancreatic islet tissue, sex glands (testicles and ovaries), placenta and hormone-producing areas of the gastrointestinal tract.
