Recent advances in vasopressin signaling in the brain: from synapse to behavior to clinical translation

Article information

J Neuromonit Neurophysiol. 2025;5(2):145-151
Publication date (electronic) : 2025 November 30
doi : https://doi.org/10.54441/jnn.2025.5.2.145
1Department of Medical Laser, Dankook University, Cheonan, Republic of Korea
2Department of Otorhinolaryngology-Head and Neck Surgery, Dankook University College of Medicine, Cheonan, Republic of Korea
Corresponding to Seung Hoon Woo E-mail. lesaby@hanmail.net
Received 2025 October 31; Revised 2025 November 10; Accepted 2025 November 10.

Abstract

Arginine vasopressin (AVP) functions not only as a peripheral hormone but also as a potent neuromodulator that shapes neural activity across molecular, circuit, and behavioral levels. In the last few years, powerful tools such as optogenetics, fiber photometry, and receptor-specific imaging have revealed new dimensions of AVP signaling in synaptic plasticity, social behavior, and psychiatric vulnerability. This review integrates discoveries across three tiers, including (1) synaptic-level mechanisms that define how AVP sculpts excitatory–inhibitory balance, (2) behavioral pathways that link AVP activity to social cognition, stress, and emotion, and (3) translational advances identifying receptor-specific therapeutic and imaging strategies. Together, these findings position AVP as a key integrator of homeostatic and social functions in the brain and highlight its emerging clinical potential.

Introduction

Arginine vasopressin (AVP) has long been recognized for its roles in water retention and cardiovascular regulation [1-3], yet its influence within the central nervous system has only recently become clear. Expressed in the hypothalamic paraventricular and supraoptic nuclei [4], while acting through V1a and V1b receptors [5], AVP modulates synaptic signaling across the limbic system, hippocampus, and brainstem [6-8]. Over the past five years, innovations in in vivo imaging and viral-tracing techniques have mapped previously unknown AVP circuits and revealed anticipatory and context-dependent modes of secretion. This review organizes recent work into a multi-scale framework, namely synaptic, circuit, and translational, to capture how AVP shapes neural computations that underline social and emotional behaviors and how these mechanisms might be harnessed to treat neuropsychiatric disorders.

Synaptic and Neuronal Mechanisms

AVP signaling at the cellular level is primarily mediated by G-protein-coupled V1a and V1b receptors, activating phospholipase C, Ca2+ influx, and MAPK cascades [9-11]. In recent research, patch-clamp and imaging studies show that AVP modulates neuronal excitability through both pre- and postsynaptic mechanisms, reducing inhibitory GABA release in olfactory bulb circuits [12,13] while increasing excitatory drive and synaptic protein expression such as PSD95 and GluA1 in hippocampal and amygdala neurons [14]. These effects collectively enhance long-term potentiation and reconfigure local oscillatory activity, aligning AVP action with mechanisms of memory and stress adaptation [15]. Crosstalk with oxytocin receptors (OTRs) further refines AVP’s impact on cell signaling, suggesting coordinated control of social and homeostatic responses at the synaptic scale [16].

In another study by Kim et al. [17], they examined how vasopressin neurons exhibit anticipatory activation before physiological disturbances occur. Using fiber photometry, optogenetics, and calcium imaging, researchers discovered that AVP neurons respond to learned, feedforward signals from higher brain centers during behaviors like drinking or salt intake, ‘before’ osmotic changes happen. This represents a shift from viewing vasopressin as purely reactive to understanding it as a predictive, anticipatory system for maintaining homeostasis.

Table 1 summarizes the method and key findings in six of the selected recent studies on vasopressin signaling in synaptic level.

Summary of the method and key findings in recent studies on vasopressin signaling in synaptic level

Circuit and Behavioral Dynamics

At the systems level, AVP neurons form widespread projections linking hypothalamic nuclei with limbic and midbrain structures including the lateral septum, amygdala, bed nucleus of the stria terminalis (BNST), and dorsal raphe [18,19]. In recent studies, circuit-specific studies combining fiber photometry and optogenetics have revealed that AVP activity anticipates osmotic or social challenges [17] and gates social investigation, aggression, and anxiety [20,21]. In the lateral septum, diminished AVP-evoked excitation produces social deficits in Shank3B+/- mice, rescuable through chemogenetic stimulation, linking disrupted AVP modulation directly to autism-related phenotypes. Additionally, AVP enhances serotonergic activation in the dorsal raphe during social interactions [22], illustrating how neuromodulatory cross-system interactions regulate affect and affiliative behavior. Collectively, these findings show that AVP acts as a circuit-level tuner of social and emotional behavior, integrating internal state and environmental cues.

In another study by Francesconi et al. [23], the group examined not only vasopressin, but together with oxytocin, how they converge on the BNST to regulate anxiety-related behaviors. Both AVP and oxytocin excite specific BNST neuron types (I and III) primarily through OTRs rather than vasopressin receptors, with inputs from hypothalamic regions (suprachiasmatic and supraoptic nuclei). Chemogenetic silencing of OTR-expressing BNST neurons increased anxiety-like behavior in fear-potentiated startle tests and reduced open-arm exploration. This demonstrates the BNST as a critical integration point where neuropeptide systems balance external threat assessment with internal physiological needs, highlighting the anxiolytic (anxiety-reducing) role of OTR-BNST neurons in helping organisms overcome threat avoidance to meet survival needs.

Table 2 summarizes the method and key findings in four of the selected recent studies on vasopressin signaling in behavior level.

Summary of the method and key findings in recent studies on vasopressin signaling in behavior level

Translational and Clinical Perspectives

Recent advances have brought AVP research closer to clinical application. Novel positron emission tomography ligands for V1a receptors [24] allow non-invasive visualization of receptor density and drug occupancy in living subjects, while measurements of circulating AVP and copeptin provide accessible biomarkers of stress and brain-body integration. Dysregulated AVP signaling has been implicated in autism spectrum disorder and mood disorders, prompting interest in selective V1b antagonists and circuit-targeted neuromodulation [25-27]. Clinical data show sex differences in relative AVP correlation structure in neurocritical patients, specifically in postmenopausal female, plasma and cerebrospinal fluid AVP levels showed a moderate positive correlation, while cerebrospinal fluid AVP and serum sodium showed a negative correlation [28]. Although overall AVP levels do not vary by sex, this correlation suggests the physiological responsiveness of AVP secretion to sodium fluctuations may be distinct in postmenopausal females. Overall, combining chemogenetic circuit control with pharmacological precision could potentially yield next-generation therapies for social and emotional dysfunctions rooted in AVP network imbalance.

Table 3 summarizes the method and key findings in four of the selected recent studies on vasopressin signaling in clinical level.

Summary of the method and key findings in recent studies on vasopressin signaling in clinical level

Future Directions

Despite rapid progress, major questions remain: how does AVP encode the valence of social stimuli, and how do receptor subtypes cooperate across time and space? Integrating spatial transcriptomics, connectomics, and computational modeling will be essential to capture the dynamic logic of AVP signaling. Comparative studies across species, including primate and human data, are needed to validate translational relevance. The field is moving toward a unified view of AVP as both a homeostatic and cognitive neuromodulator, bridging physiological regulation with higher-order social cognition.

Conclusion

Across the past 5 years, vasopressin research has evolved from descriptive neuroendocrinology to multi-scale systems neuroscience. Evidence now shows that AVP coordinates activity from the synapse to the network to the organism, integrating social, emotional, and physiological domains. Understanding this hierarchy opens new therapeutic pathways and redefines vasopressin as a master regulator of adaptive brain states.

Notes

Funding

None.

Conflict of Interest

Seung Hoon Woo is the Editor-in-Chief of the journal, but was not involved in the review process of this manuscript. Otherwise, there is no conflict of interest to declare.

Data Availability

None.

Author Contributions

Conceptualization: HKK; Investigation: HKK; Writing–original draft: HKK; Writing–review & editing: all authors.

References

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Article information Continued

Table 1.

Summary of the method and key findings in recent studies on vasopressin signaling in synaptic level

Article title Author Year Summary Reference No.
Neural basis for regulation of vasopressin secretion by anticipated disturbances in osmolality Kim A, Madara JC, Wu C, Andermann ML, Lowell BB 2021 Fiber photometry, optogenetics, and in vivo calcium imaging in mice were used to monitor and manipulate vasopressin (AVP) neurons in the hypothalamic supraoptic and paraventricular nuclei. AVP neurons were activated not only by actual increases in plasma osmolality but also anticipatorily, before osmotic disturbances occurred, during behaviors such as drinking or salt intake. This anticipatory activation suggests that vasopressin secretion is partly governed by learned, feedforward signals from higher brain centers, allowing the body to pre-emptively maintain fluid balance. [17]
Co-stimulation of oxytocin and arginine-vasopressin receptors affect hypothalamic neurospheroid size Salehi MS, Neumann ID, Jurek B, Pandamooz S 2021 3D hypothalamic neurospheroids derived from rat neural stem cells were cultured and treated with oxytocin, vasopressin, or both to assess changes in growth and morphology. Using immunofluorescence and confocal microscopy, the researchers found that co-stimulation of oxytocin and vasopressin receptors significantly increased neurospheroid size and altered cell organization compared to single-hormone treatments. These findings suggest synergistic interactions between oxytocin and vasopressin signaling pathways that influence hypothalamic neural development and structural plasticity. [16]
Vasopressin acts as a synapse organizer in limbic regions by boosting PSD95 and GluA1 expression Zhang L, Padilla-Flores T, Hernández VS, Zetter MA, Campos-Lira E, Escobar LI, et al. 2022 Mouse brain slice cultures and primary hippocampal neurons were used to investigate how vasopressin influences synaptic structure and protein expression. Through immunostaining, confocal microscopy, and Western blotting, they found that vasopressin treatment significantly increased levels of PSD95 and GluA1, key markers of excitatory synapses, particularly in the amygdala and hippocampus. These findings indicate that vasopressin functions as a synaptic organizer, enhancing excitatory synapse formation and potentially modulating limbic circuit plasticity underlying social behavior. [14]
Arginine vasopressin, synaptic plasticity, and brain networks Marcinkowska AB, Biancardi VC, Winklewski PJ 2022 This review analyzed experimental and neuroimaging studies to describe how AVP influences neural signaling from the synaptic to the network level. Evidence was summarized about AVP modulating glutamatergic and GABAergic transmission, enhancing long-term potentiation in hippocampal circuits, particularly via V1a and V1b receptors, and altering brain oscillations and BOLD connectivity patterns linked to emotional and cognitive processes. Overall, AVP is shown to act as a neuromodulator that fine-tunes synaptic plasticity and large-scale network synchronization, shaping attention, memory, and social behavior in a sex-dependent manner. [15]
Vasopressin differentially modulates the excitability of rat olfactory bulb neuron subtypes Suyama H, Bianchini G, Lukas M 2024 Acute olfactory bulb slices from juvenile rats were used to perform whole-cell patch-clamp electrophysiology and two-photon calcium imaging, investigating how AVP affects excitatory and inhibitory neurons during simulated odor stimulation. AVP was found to excite inhibitory interneurons while reducing the excitability of mitral and tufted projection neurons, effectively enhancing inhibitory control within the olfactory bulb. These results reveal that vasopressin fine-tunes olfactory signal processing by shifting the balance toward inhibition, which may underlie its role in modulating social odor discrimination. [13]
Activation of arginine vasopressin receptor 1a reduces inhibitory synaptic currents at reciprocal synapses in the mouse accessory olfactory bulb Taniguchi M, Murata Y, Yamaguchi M, Kaba H 2024 Using whole-cell patch-clamp recordings in acute AOB slices from mice, how AVP modulates synaptic transmission between mitral and granule cells was examined. AVP was found to significantly reduce inhibitory postsynaptic currents at dendrodendritic synapses via activation of V1a receptor, while having no effect through V1b receptor and no postsynaptic influence on GABA responses. These results indicate that AVP decreases GABAergic transmission presynaptically by inhibiting calcium currents in granule cells, suggesting a mechanism through which vasopressin modulates pheromonal memory and social recognition processing in the AOB. [12]

AVP, arginine vasopressin; BOLD, blood-oxygen-level-dependent; AOB, accessory olfactory bulb.

Table 2.

Summary of the method and key findings in recent studies on vasopressin signaling in behavior level

Article title Author Year Summary Reference No.
Oxytocin, vasopressin, and social behavior: from neural circuits to clinical opportunities Rigney N, de Vries GJ, Petrulis A, Young LJ 2022 This review synthesized recent studies using molecular genetics, viral tracing, and optogenetics to map OXT and vasopressin (AVP) neural circuits that regulate social behaviors across mammals. How OXT and AVP neurons in the hypothalamus and extended amygdala interact with dopamine and serotonin pathways to shape social recognition, bonding, aggression, and parental care in a sex-specific manner were highlighted. Both peptides act through distinct yet overlapping circuits to tune social motivation and memory, offering translational potential for disorders like autism spectrum disorder when circuit-specific mechanisms are targeted. [20]
Social interactions increase activation of vasopressin-responsive neurons in the dorsal raphe Patel TN, Caiola HO, Mallari OG, Blandino KL, Goldenthal AR, Dymecki SM, et al. 2022 C-Fos immunohistochemistry and receptor-specific labeling were used in mice to identify neurons in the dorsal raphe nucleus that respond to AVP during social interaction tests. Social exposure significantly increased c-Fos expression in AVP-receptor-expressing serotonergic neurons, indicating heightened neural activation linked to social behavior. These findings suggest that vasopressin modulates serotonergic circuits in the dorsal raphe to facilitate social information processing and behavioral adaptation. [22]
Impaired vasopressin neuromodulation of the lateral septum leads to social behavior deficits in Shank3B+/- male mice Bortolozzo-Gleich MH, Bouisset G, Geng L, Pino AR, Nomura Y, Han S, et al. 2025 Fiber photometry, optogenetics, chemogenetics, and electrophysiology were used to examine AVP signaling in the LS of Shank3B+/- mice, a model of autism spectrum disorder. AVP-evoked excitation of LS neurons and social investigation behavior were both diminished in mutant mice due to disrupted postsynaptic V1a receptor signaling. Restoring AVP activity in the LS rescued social deficits, demonstrating that impaired AVP modulation of septal circuits contributes directly to the social behavior impairments associated with Shank3B deficiency. [21]
Vasopressin and oxytocin excite BNST neurons via oxytocin receptors, which reduce anxious arousal Francesconi W, Olivera-Pasilio V, Berton F, Olson SL, Chudoba R, Monroy LM, et al. 2025 How AVP and OXT regulate anxiety-related behaviors through the BNST in male rats was investigated using patch-clamp electrophysiology, optogenetics, and behavioral testing. Both AVP and OXT excite specific BNST neurons primarily through OTRs rather than vasopressin receptors, with AVP inputs arriving from hypothalamic regions including the suprachiasmatic nucleus and supraoptic nucleus. Chemogenetic silencing of OTR-expressing BNST neurons increased anxiety-like behavior in fear-potentiated startle tests and reduced open-arm exploration in the elevated plus maze, demonstrating that these neurons play an anxiety-reducing role by helping balance threat responses with physiological needs. [23]

OXT, oxytocin; AVP, arginine vasopressin; LS, lateral septum; BNST, bed nucleus of the stria terminalis; OTR, oxytocin receptor.

Table 3.

Summary of the method and key findings in recent studies on vasopressin signaling in clinical level

Article title Author Year Summary Reference No.
Efficacy and safety of TS-121, a novel vasopressin V1B receptor antagonist, as adjunctive treatment for patients with major depressive disorder: a randomized, double-blind, placebo-controlled study Kamiya M, Sabia HD, Marella J, Fava M, Nemeroff CB, Umeuchi H, et al. 2020 This study evaluated the efficacy and safety of TS-121, a selective vasopressin V1b receptor antagonist, as adjunctive therapy in adults with major depressive disorder who had inadequate response to antidepressants. Participants were randomly assigned to receive TS-121 (two fixed doses) or placebo for 6 weeks. Although the overall treatment group did not show a statistically significant improvement versus placebo, a subgroup of patients with higher baseline HPA-axis activity (as indicated by cortisol levels) showed greater symptom improvement with TS-121. These results suggest that V1b receptor antagonism may be particularly beneficial for depression subtypes associated with HPA-axis hyperactivity. [27]
Sex-specific issues of central and peripheral arginine-vasopressin concentrations in neurocritical care patients Podtschaske AH, Martin J, Ulm B, Jungwirth B, Kagerbauer SM 2022 AVP concentrations in simultaneously collected CSF, plasma, and saliva samples from 30 neurocritical care patients (13 male, 13 postmenopausal female, 4 premenopausal female) were investigated to assess correlations between central and peripheral compartments. Only weak correlations between AVP concentrations across compartments in the overall population, with no significant sex differences in absolute AVP levels were found. However, postmenopausal women showed a significant moderate positive correlation between plasma and CSF AVP, as well as a significant negative correlation between CSF AVP and serum sodium. These findings suggest that while absolute AVP concentrations don’t differ by sex, the mechanisms of AVP secretion and response to physiological triggers (like sodium changes) may differ between males and females, particularly in postmenopausal women. [28]
Discovery and evaluation of a novel 18F-labeled vasopressin 1a receptor PET ligand with peripheral binding specificity Hu J, Li Y, Dong C, Wei H, Liao K, Wei J, et al. 2024 A novel fluorine-18-labeled PET radioligand, [18F]V1A-2303, were developed for imaging V1a receptors, through chemical synthesis, radiolabeling, and comprehensive in vitro and in vivo characterization including cell uptake assays, autoradiography, biodistribution studies in mice, and PET imaging with arterial blood sampling in rhesus monkeys. [18F]V1A-2303 demonstrated high binding affinity (Ki=0.46 nmol/L) and excellent selectivity for V1a receptors over other AVP receptor subtypes, with strong specific binding confirmed in peripheral tissues (particularly liver) through blocking studies using V1a antagonists like balovaptan. However, while the tracer showed moderate brain uptake in non-human primates (peak SUV=1.6), kinetic modeling revealed a lack of specific binding in the brain, indicating that [18F]V1A-2303 is suitable for imaging peripheral V1a receptors but requires further optimization for central nervous system applications. [24]
A pharmacological and brain imaging study of human vasopressin AVP1BR receptor functional polymorphisms Alacreu-Crespo A, Olié E, Manière M, Deverdun J, Lebars E, Corbani M, et al. 2025 Three V1b receptor polymorphisms were investigated through in vitro pharmacological characterization in transfected HEK293 cells and fMRI brain imaging in 35 healthy men during an emotional face recognition task. Cells expressing K65N and R364H variants showed significantly reduced inositol phosphate accumulation (22%–35% decrease) following AVP stimulation, while the G191R variant showed increased accumulation (49% increase), all with similar receptor expression and membrane localization; additionally, fMRI revealed that homozygotes (GG genotype) for K65N and R364H polymorphisms exhibited greater activation in motor areas, visual areas, hippocampus, and putamen when viewing angry versus neutral faces compared to heterozygotes. These findings suggest that V1b receptor polymorphisms alter receptor signaling efficiency and brain responses to emotional stimuli, potentially serving as biomarkers for psychiatric disorders involving HPA axis dysregulation and abnormal social behavior. [25]

HPA, hypothalamic-pituitary-adrenal; AVP, arginine vasopressin; CSF, cerebrospinal fluid; PET, positron emission tomography; SUV, standard uptake value; fMRI, functional magnetic resonance imaging.