Modulation of Oxytocin Release by Internal Calcium Stores

Abstract

This chapter elucidates the role of depolarization-induced oxytocin (OT) vs. arginine vasopressin (AVP) secretion in the absence of external calcium, and calcium release from ryanodine-sensitive internal stores as a significant physiological contributor to neuropeptide secretion from hypothalamic neurohypophysial system (HNS) terminals. This has important therapeutic implications, given that exogenous administration of OT to children with autism spectrum disorders (ASD) has shown some success in improving social behavior and lowering anxiety. However, this nonspecific treatment has side effects, including seizures, increased heart rate variability, and psychotic symptoms. Alternatively, facilitating the physiological neuronal release of OT but not AVP from the HNS via modulation of ryanodine vs. inositol triphosphate receptor (IP3R) calcium stores would specifically facilitate central vs. peripheral OT release in ASD patients.