Prolactin's diverse physiological roles and the clinical significance of hyperprolactinemia.

Objectives: This review aims to provide a comprehensive overview of prolactin biology, encompassing its molecular heterogeneity, neuroendocrine regulation, and multifaceted roles in human health and disease, focusing on hyperprolactinemia.

Material and methods: A comprehensive literature search was conducted to identify relevant articles on prolactin biology, physiology, and related disorders.

Results: Prolactin exists in various molecular forms, including monomeric prolactin, 'big prolactin', and macroprolactin, each with distinct biological activities. Prolactin secretion is tightly regulated by a complex interplay of hypothalamic factors, primarily dopamine and thyrotropin-releasing hormone (TRH). Prolactin exerts diverse physiological effects, including roles in lactation, reproduction, metabolic homeostasis, immune function, and neuroprotection. Dysregulation of prolactin secretion, particularly hyperprolactinemia, can lead to significant clinical manifestations. Accurate diagnosis of hyperprolactinemia requires a thorough evaluation of potential etiologies, including pituitary adenomas, medications, and systemic diseases. Management strategies encompass pharmacological therapies, such as dopamine agonists and surgical interventions.

Conclusions: Prolactin is a multifaceted neuroendocrine hormone with a diverse range of physiological functions and clinical implications. Understanding the complexities of prolactin biology is essential for recognizing and managing prolactin-related disorders, such as hyperprolactinemia, and for developing novel therapeutic strategies that target prolactin signaling pathways.