In the study of steroid hormones, it is essential to understand that these hormones are derived from cholesterol, which serves as their precursor molecule. Steroid hormones are a type of bio-signaling molecule released by cells or glands, traveling through the body to affect distant cells. They can be classified into five distinct groups based on their physiological responses: androgens, estrogens, progestins, glucocorticoids, and mineralocorticoids.
Androgens, such as testosterone, are primarily responsible for male sexual development and are produced by the gonads, which include the testes. Estrogens, like estradiol, control female sexual development and are also produced by the gonads, specifically the ovaries. Progestins, exemplified by progesterone, play a crucial role in regulating the menstrual cycle and supporting pregnancy in females.
On the other hand, glucocorticoids, such as cortisol, are produced by the adrenal cortex and are involved in the metabolism of carbohydrates, proteins, and lipids, facilitating the breakdown of these macromolecules. Mineralocorticoids, including aldosterone, also produced by the adrenal cortex, are vital for regulating kidney excretion of salt and water, thus influencing fluid balance in the body.
To aid in memorization of these classes, a mnemonic can be utilized: the first letters of "angry elves probably get mad" correspond to androgens, estrogens, progestins, glucocorticoids, and mineralocorticoids, respectively. This playful association can help reinforce the understanding of the steroid hormone classes and their functions.
Overall, this introduction to steroid hormones sets the stage for deeper exploration of their specific functions and roles in the body, which will be covered in subsequent lessons.