3. Types and Mechanisms of Hormonal Action

Learning Objectives:

  • Differentiate between peptide, steroid, and amine hormones.
  • Describe how hormones act through receptors.

Introduction

The endocrine system plays a vital role in maintaining homeostasis by regulating physiological processes through the secretion of hormones. 

Unlike neural signals that act rapidly and locally, hormonal signals are typically slower but have prolonged and widespread effects.

Understanding how hormones function involves two key aspects: the types of hormones based on their chemical structure and origin, and the mechanisms through which they exert their effects on target cells.

The nature of a hormone—whether it's water-soluble or lipid-soluble—determines how it interacts with receptors and initiates a response within the body. These interactions form the foundation of hormonal signaling pathways that influence gene expression, enzyme activity, and cellular function.

Now, let’s explore the types of hormones and the mechanisms of their action in more detail.