STEROID HORMONES Meaning and
Definition
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Steroid hormones are a class of hormones that are derived from cholesterol and have a similar structure characterized by four interconnected carbon rings. They are synthesized and secreted by the endocrine glands, mainly the adrenal cortex, testes, and ovaries, but also in small quantities by other tissues such as the liver and placenta.
Steroid hormones exert their effects by binding to specific intracellular receptors located within the target cells. Once inside the cell, they interact with these receptors, forming a hormone-receptor complex that can directly influence gene expression, leading to the production of specific proteins or modulation of cellular processes.
There are several types of steroid hormones, including glucocorticoids, mineralocorticoids, and sex hormones. Glucocorticoids, such as cortisol, regulate various metabolic processes, immune responses, and stress reactions. Mineralocorticoids, such as aldosterone, regulate electrolyte and fluid balance in the body. Sex hormones include estrogens, progesterone, and testosterone, which play important roles in the development and maintenance of reproductive systems and secondary sexual characteristics.
Due to their pivotal role in various physiological processes, steroid hormones have significant impacts on growth, development, metabolism, reproduction, and immune responses. Dysfunction or imbalance in steroid hormone levels can lead to various disorders, such as Addison's disease, Cushing's syndrome, and conditions related to reproductive health. Steroid hormones are also used as medications, such as corticosteroids, for their anti-inflammatory and immunosuppressive properties.
Etymology of STEROID HORMONES
The word "steroid hormones" is made up of two parts: "steroid" and "hormones".
The term "steroid" comes from the German word "Steroide", which was first used in 1920. It is derived from the Greek word "stērós", meaning "solid" or "stiff". In the field of chemistry, steroids refer to a large class of organic compounds that have a characteristic structure consisting of four fused carbon rings.
The word "hormone" has its roots in the Greek word "horman", meaning "to excite" or "to set in motion". It was first used in English in the early 20th century to describe chemical messengers produced by the endocrine glands, which regulate various bodily functions.
So when combined, "steroid hormones" refers to a specific group of hormones that are derived from or related to steroids.
