Adrenal glands and stress hormones

Welcome to this lecture on adrenal glands and stress hormones, providing an overview of the structure and functions of the adrenal glands, including their distinct regions, the cortex and medulla, and the hormones they produce. We will discuss how these hormones regulate stress responses, metabolism, fluid balance, and blood pressure, and examine the feedback mechanisms that maintain balance. Additionally, we will explore common adrenal disorders such as Addison's disease and Cushing's syndrome, highlighting their impact on health. Let us begin by picturing the adrenal glands, two small but vital structures that sit atop each kidney like little caps. Each adrenal gland is composed of two regions, the outer adrenal cortex and inner adrenal medulla. The cortex has three zones producing steroid hormones, while the medulla synthesizes catecholamines. Despite their size, these glands are fundamental for maintaining homeostasis, stress response, metabolism, fluid balance, immune activity, and blood pressure. The adrenal cortex and medulla are both functionally and embryologically distinct. The cortex, derived from mesoderm, produces essential steroid hormones, mineral corticoids, glucocorticoids, and androgens. Aldosterone regulates electrolyte and fluid balance, while cortisol influences metabolism and stress responses. The medulla originating from neural crest cells is part of the sympathetic nervous system and secretes