Dual Pathways Coupled to Oxytocin Molecular Signals in Cultured Astrocytes

Area of Science:

• Neuroscience
• Cell Biology
• Molecular Signaling

Background:

• Oxytocin's role in glial cell function is gaining recognition.
• Previous work showed oxytocin can excite or inhibit astrocyte calcium (Ca2+) signals and glutamate release.

Purpose of the Study:

• To investigate oxytocin receptor (OTR) expression in astrocytes.
• To determine the effects of OTR activation on astrocyte Ca2+ signals and glutamate release.

Main Methods:

• Primary cortical astrocytes were used.
• Confocal imaging assessed OTR presence.
• Oxytocin and biased agonists (carbetocin, atosiban) were applied to measure Ca2+ signals and glutamate release.

Main Results:

• Oxytocin receptors are present in both astrocyte cell bodies (soma) and processes.
• Oxytocin induced dual responses: facilitation and inhibition of Ca2+ signals and glutamate release.
• Carbetocin mimicked facilitation (Gq pathway), while atosiban mimicked inhibition (Gi pathway).

Conclusions:

• Astrocytes express functional oxytocin receptors.
• Oxytocin mediates opposing effects on astrocyte activity via distinct G protein signaling pathways (Gq and Gi).
• Isolated astrocytes can be used to study astrocytic oxytocin molecular signaling.