Endocrine system

The endocrine system is not a single molecular target, receptor, or protein, but rather a complex network of glands and organs that secrete hormones directly into the bloodstream to regulate numerous physiological processes, including growth, metabolism, development, stress response, and reproduction[1][4][7]. The system includes glands such as the pituitary, thyroid, parathyroid, adrenal, pineal, pancreas, testes, ovaries, and hypothalamus. These glands communicate via hormones to maintain homeostasis in the body. Disorders of the endocrine system are diverse and can involve hormone excess, deficiency, or abnormal tissue growth (e.g., endocrine tumors)[1][7]. Because the term "endocrine system" does not refer to a discrete molecule, protein, receptor, or gene, it cannot serve as a therapeutic target in the conventional sense; rather, individual components (such as specific hormone receptors or enzymes) function as molecular targets for drugs and other therapies[8][3].