Role of Serotonin in Mammary Gland Development and Lactation Regulation in Dairy Animals: A Review

Abstract

The aim of this review was to look in to the role of serotonin in the of mammary gland development and lactation regulation in dairy animals. In dairy animals, the dynamic interplay of endocrine hormones and locally produced factors such as serotonin regulates udder gland development and lactation. Serotonin (5-hydroxytryptamine, 5-HT) is a central neurotransmitter that influences mammary development and lactation in a variety of mammals. Its action is mediated by receptors found in a variety of mammary tissues. Serotonin played a significant role in the dilatation of the mammary alveolar space. Mammary 5-HT is used to regulate lactation, initiate the shift from the early stages of involution, and accelerate calcium mobilization from the skeleton. 5-HT is a nearby or local signal that controls milk secretion and promotes the formation of parathyroid hormone–related peptide (PTHrP) in several animals. According to various studies, serotonin influences milk yield and composition. Intrinsic 5-HT, which is generated inside the mammary epithelium, is vital in managing milk volume homeostasis in many species of mammals. Furthermore, when the udder gland is full of milk, 5-HT sends a negative feedback signal to the mammary epithelium, inhibiting further milk supply. Serotonin can limit milk production via a negative feedback loop by countering prolactin synthesis of mammary gland growth and lactation. Cellular connections (adherens junctions, desmosomes, and gap junctions), TPH1 induction, secretory activation, and pharmacological effects all have an impact on serotonergic control of lactation. Thus, serotonins linked with their receptors and play a crucial role in mammary gland development and lactation regulation.