What is the Origin of Systemic Chemical Messengers?

This is a descriptive, translational term used to unify the various classes of signaling molecules under a functional umbrella, highlighting their role in long-distance communication. The "Systemic" aspect differentiates them from local paracrine or autocrine signals, emphasizing their circulation in the blood. This term is foundational to the study of endocrinology and integrative physiology.

What is the Mechanism of Systemic Chemical Messengers?

Upon secretion, these messengers circulate, either freely or bound to carrier proteins, until they encounter a cell expressing the appropriate receptor. Binding to this receptor initiates a specific signal transduction cascade inside the target cell, ultimately leading to a change in cellular function, such as enzyme activation, protein synthesis, or gene expression. The specificity of the message is determined by the unique structure of the messenger and the selective distribution of its corresponding receptor throughout the body.

Systemic Chemical Messengers ∞ Area

Systemic Chemical Messengers

Meaning

A broad category encompassing all signaling molecules, including classical hormones, neuropeptides, cytokines, and growth factors, that are secreted by one cell or tissue and travel through the circulatory system to exert effects on distant target cells throughout the body. These messengers constitute the body’s primary communication system, coordinating growth, metabolism, reproduction, and stress response across diverse physiological domains. They are the language of inter-organ communication and metabolic control.