Insulin secretion by beta cells is defined as the stimulus-secretion coupling process within the endocrine pancreas where glucose-dependent electrical signaling triggers vesicular exocytosis. This mechanism operates under the formal framework of neuroendocrine physiology, specifically functioning as the primary negative feedback controller for systemic blood glucose homeostasis. The concept represents a core physiological rule wherein metabolic fuel levels directly modulate peptide hormone release rates to maintain metabolic steady state.
Prerequisite chain context: requires Glucose Homeostasis Regulation.