Exploring the diversity and potential functional characteristics of microbiota associated with different compartments of Schisandra chinensis.

Introduction: Symbiotic microbial have a significant impact on the growth and metabolism of medicinal plants. Schisandra chinensis is a very functionally rich medicinal herb; however, its microbial composition and diversity have been poorly studied. Methods: In the present study, the core microbiomes associated with the rhizospheric soil, roots, stems, leaves, and fruits of S. chinensis from six geographic locations were analyzed by a macro-genomics approach. Results: Alpha and beta diversity analyses showed that the diversity of microbial composition of S. chinensis fruits did not differ significantly among the geographic locations as compared to that in different plant compartments. Principal coordinate analysis showed that the microbial communities of S. chinensis fruits from the different ecological locations were both similar and independent. In all S. chinensis samples, Proteobacteria was the most dominant bacterial phylum, and Ascomycota and Basidiomycota were the most dominant fungal phyla. Nitrospira, Bradyrhizobium, Sphingomonas, and Pseudomonas were the marker bacterial populations in rhizospheric soils, roots, stems and leaves, and fruits, respectively, and Penicillium, Golubevia, and Cladosporium were the marker fungal populations in the rhizospheric soil and roots, stems and leaves, and fruits, respectively. Functional analyses showed a high abundance of the microbiota mainly in biosynthesis. Discussion: The present study determined the fungal structure of the symbiotic microbiome of S. chinensis, which is crucial for improving the yield and quality of S. chinensis.

The complete chloroplast genome of Lagochilus ilicifolius Bunge ex Bentham, Labiat. Gen. 1834 (Lamiaceae) and its phylogenetic analysis.

Lagochilus ilicifolius Bunge ex Bentham, Labiat. Gen is a perennial herb with much-branched stems native to Nei Mongol, Ningxia, Gansu, N Shaanxi. It can be used clinically as a hemostatic agent. The chloroplast genome length is 151,466 bp. It contained two inverted repeat regions of 25,660 bp each, a large single-copy region of length 82,504 bp, and a small single-copy region of length 17,642 bp. Also, the GC content is 38.6%. There were 133 genes annotated, including 88 known protein-coding genes, 37 tRNAs, and eight rRNAs. The phylogenetic tree was constructed using Bayesian method for plastome data of 29 species. The entire chloroplast genome of L. ilicifolius within the Lamiaceae is the first to reveal genetic taxonomy at the molecular level, and the new phylogenetic tree data can be used for future evolutionary studies.

Comparative analysis of chloroplast genomes of Pulsatilla species reveals evolutionary and taxonomic status of newly discovered endangered species Pulsatilla saxatilis.

BACKGROUND: Pulsatilla saxatilis, a new species of the genus Pulsatilla has been discovered. The morphological information of this species has been well described, but its chloroplast genome characteristics and comparison with species of the same genus remain to be reported. RESULTS: Our results showed that the total length of chloroplast (cp.) genome of P. saxatilis is 162,659 bp, with a GC content of 37.5%. The cp. genome contains 134 genes, including 90 known protein-coding genes, 36 tRNA genes, and 8 rRNA genes. P. saxatilis demonstrated similar characteristics to other species of genus Pulsatilla. Herein, we compared cp. genomes of 10 species, including P. saxatilis, and found that the cp. genomes of the genus Pulsatilla are extremely similar, with a length of 162,322-163,851 bp. Furthermore, The SSRs of Pulsatilla ranged from 10 to 22 bp in length. Among the four structural regions of the cp. genome, most long repeats and SSRs were detected in the LSC region, followed by that in the SSC region, and least in IRA/ IRB regions. The most common types of long repeats were forward and palindromic repeats, followed by reverse repeats, and only a few complementary repeats were found in 10 cp. genomes. We also analyzed nucleotide diversity and identified ccsA_ndhD, rps16_trnK-UUU, ccsA, and rbcL, which could be used as potential molecular markers for identification of Pulsatilla species. The results of the phylogenetic tree constructed by connecting the sequences of high variation regions were consistent with those of the cp. gene phylogenetic tree, and the species more closely related to P. saxatilis was identified as the P. campanella. CONCLUSION: It was determined that the closest species to P. saxatilis is P. campanella, which is the same as the conclusion based on pollen grain characteristics, but different from the P. chinensis determined based on morphological characteristics. By revealing information on the chloroplast characteristics, development, and evolution of the cp. genome and the potential molecular markers, this study provides effective molecular data regarding the evolution, genetic diversity, and species identification of the genus Pulsatilla.

Effects of paternal deprivation on empathetic behavior and the involvement of oxytocin receptors in the anterior cingulate cortex.

Paternal deprivation (PD) impairs social cognition and sociality and increases levels of anxiety-like behavior. However, whether PD affects the levels of empathy in offspring and its underlying mechanisms remain unknown. The present study found that PD increased anxiety-like behavior in mandarin voles (Microtus mandarinus), impaired sociality, reduced the ability of emotional contagion, and the level of consolation behavior. Meanwhile, PD reduced OT neurons in the paraventricular nucleus (PVN) in both male and female mandarin voles. PD decreased the level of OT receptor (OTR) mRNA in the anterior cingulate cortex (ACC) of male and female mandarin voles. Besides, OTR overexpression in the ACC reversed the PD-induced changes in anxiety-like behavior, social preference, emotional contagion, and consolation behavior. Interference of OTR expression in the ACC increased levels of anxiety-like behaviors, while it reduced levels of sociality, emotional contagion, and consolation. These results revealed that the OTR in the ACC is involved in the effects of PD on empathetic behaviors, and provide mechanistic insight into how social experiences affect empathetic behaviors.

The complete chloroplast genome of Pulsatilla chinensis f. alba D. K. Zang (Ranunculaceae, Pulsatilla Miller).

Pulsatilla chinensis f. alba D. K. Zang 1993 is a forma of Pulsatilla chinensis (Bge.) Regel, the root of P. chinensis is traditional Chinese medicine called Pulsatillae radix. The biggest difference between P. chinensis f. alba and P. chinensis is that P. chinensis f. alba sepals is white. The complete chloroplast genome of P. chinensis f. alba was sequenced using the Illumina NovaSeq platform for the first time. The lengths of the genome, large single-copy (LSC), small single-copy (SSC), two inverted repeats (IRs), and GC content were 163,654 bp, 82,355 bp, 19,069 bp, 31,115 bp, and 37.2%, respectively. It had 134 genes, including 90 protein-coding genes, 36 tRNA genes, and eight rRNA genes. The maximum-likelihood tree indicated that P. chinensis f. alba had a closer relationship with P. chinensis. This study would provide a theoretical basis for the further study of Pulsatilla plants genetics phylogenetic research.

The complete chloroplast genome of Grewia biloba var. parviflora (Bunge) Hand.-Mazz. (Malvaceae).

Grewia biloba var. parviflora (Bunge) Hand.-Mazz. (1933), a shrub or small tree, is native to northern and southern China. It is an excellent relief and medicinal plant. The complete chloroplast genome is 158,043 bp in length, with a large single-copy region of 86,957 bp, a small single-copy region of 20,138 bp, two inverted repeat regions of 25,474 bp each, and a GC content of 37.4%. There were 129 genes annotated, including 84 known protein-coding genes, 37 tRNAs, and eight rRNAs. The phylogenetic trees are constructed using plastome data from 38 species and the maximum-likelihood method. The results of the chloroplast genome-wide analysis and the phylogenetic tree show the taxonomic phylogeny of the G. biloba var. parviflora in relation to other species, increasing the accuracy of the phylogenetic classification of the plant.

The effect of plant compartment and geographical location on shaping microbiome of Pulsatilla chinensis.

The plant-associated microbiome has an effect on plant growth. Pulsatilla chinensis (Bge.) Regel is an important Chinese medicinal plant. Currently, there is little understanding of the P. chinensis-associated microbiome and its diversity and composition. Here, the core microbiome associated with the root, leaf, and rhizospheric soil compartments of P. chinensis from five geographical locations was analyzed by the metagenomics approach. The alpha and beta diversity analysis showed that the microbiome associated with P. chinensis was shaped by the compartment, especially in the bacterial community. The geographical location had little influence on microbial community diversity associated with root and leaf. Hierarchical clustering distinguished the microbial communities of rhizospheric soil based on their geographical location and among the soil properties, pH was showed the more stronger effect on the diversity of rhizospheric soil microbial communities. Proteobacteria was the most dominant bacterial phylum in the root, leaf, and rhizospheric soil. Ascomycota and Basidiomycota were the most dominant fungal phyla in different compartments. Rhizobacter, Anoxybacillus, and IMCC26256 were the most important marker bacterial species for root, leaf, and rhizospheric soil screened by random forest, respectively. The fungal marker species for root, leaf, and rhizospheric soil were not only different across the compartments but also the geographical locations. Functional analysis showed that P. chinensis-associated microbiome had the similar function which had no obvious relationship with geographical location and compartment. The associated microbiome indicated in this study can be used for identifying microorganisms related to the quality and growth of P. chinensis. KEY POINTS: • Microbiome associated with P. chinensis was shaped by the compartment • Microbiome composition and abundance associated with rhizospheric soil were affected by the geographical location • Compared with fungi, bacterial associated with P. chinensis composition and diversity were more stable in different geographical locations and compartments.

Involvement of Serotonergic Projections from the Dorsal Raphe to the Medial Preoptic Area in the Regulation of the Pup-Directed Paternal Response of Male Mandarin Voles.

Male mammals display different paternal responses to pups, either attacking or killing the young offspring, or contrastingly, caring for them. The neural circuit mechanism underlying the between-individual variation in the pup-directed responsiveness of male mammals remains unclear. Monogamous mandarin voles were used to complete the present study. The male individuals were identified as paternal and infanticidal voles, according their behavioral responses to pups. It was found that the serotonin release in the medial preoptic area (MPOA), as well as the serotonergic neuron activity, significantly increased upon licking the pups, but showed no changes after attacking the pups, as revealed by the in vivo fiber photometry of the fluorescence signal from the 5-HT 1.0 sensor and the calcium imaging indicator, respectively. It was verified that the 5-HTergic neural projections to the MPOA originated mainly from the ventral part of the dorsal raphe (vDR). Furthermore, the chemogenetic inhibition of serotonergic projections from the vDR to the MPOA decreased the paternal behaviors and shortened the latency to attack the pups. In contrast, the activation of serotonergic neurons via optogenetics extended the licking duration and inhibited infanticide. Collectively, these results elucidate that the serotonergic projections from the vDR to the MPOA, a previously unrecognized pathway, regulate the paternal responses of virgin male mandarin voles to pups.

Oxytocin treatments or activation of the paraventricular nucleus-the shell of nucleus accumbens pathway reduce adverse effects of chronic social defeat stress on emotional and social behaviors in Mandarin voles.

Chronic social stress can cause psychological disease. Although oxytocin (OT) has been showed to modulate effects of chronic social defeat stress (CSDS) on emotional and social behaviors, however, how OT circuits mediate effects of CSDS on emotional and social abnormalities remains unclear. Here, we found that repeated intraperitoneal OT administration in the process of CSDS buffered adverse effects of CSDS on emotional and social behaviors in mandarin voles (Microtus mandarinus) of both sexes except no effect on depression-like behavior of males. Repeated OT treatments during CSDS prevented decrease of oxytocin receptors in nucleus accumbens (NAc) in females, but produced no effects on males. Furthermore, using designer receptors exclusively activated by designer drugs (DREADDs)-based chemogenetic tools, we determined that the activation of the paraventricular nucleus (PVN)-the shell of NAc (NAcs) projections before social defeat during CSDS process significantly prevented the increase of the anxiety-like behaviors and social avoidance induced by CSDS in both sexes, and reversed the depressive-like behaviors induced by CSDS only in females. Besides, optogenetic activation of PVN-NAcs projections after CSDS reduced anxiety-like behaviors and increased levels of sociality. Collectively, we suggest that PVN-NAcs projections modulate emotional and social behaviors during or after the process of CSDS sex-specifically, although AAV viruses did not specifically infect OT neurons. These findings offer potential targets for preventing or treating emotional and social disorders induced by chronic stress.

The burdock database: a multi-omic database for Arctium lappa, a food and medicinal plant.

BACKGROUND: Burdock is a biennial herb of Asteraceae found in Northern Europe, Eurasia, Siberia, and China. Its mature dry fruits, called Niu Bang Zi, are recorded in various traditional Chinese medicine books. With the development of sequencing technology, the mitochondrial, chloroplast, and nuclear genomes, transcriptome, and sequence-related amplified polymorphism (SRAP) fingerprints of burdock have all been reported. To make better use of this data for further research and analysis, a burdock database was constructed. RESULTS: This burdock multi-omics database contains two burdock genome datasets, two transcriptome datasets, eight burdock chloroplast genomes, one burdock mitochondrial genome, one A. tomentosum chloroplast genome, one A. tomentosum mitochondrial genome, 26 phenotypes of burdock varieties, burdock rhizosphere-associated microorganisms, and chemical constituents of burdock fruit, pericarp, and kernel at different growth stages (using UPLC-Q-TOF-MS). The wild and cultivation distribution of burdock in China was summarized, and the main active components and pharmacological effects of burdock currently reported were concluded. The database contains ten central functional modules: Home, Genome, Transcriptome, Jbrowse, Search, Tools, SRAP fingerprints, Associated microorganisms, Chemical, and Publications. Among these, the "Tools" module can be used to perform sequence homology alignment (Blast), multiple sequence alignment analysis (Muscle), homologous protein prediction (Genewise), primer design (Primer), large-scale genome analysis (Lastz), and GO and KEGG enrichment analyses (GO Enrichment and KEGG Enrichment). CONCLUSIONS: The database URL is http://210.22.121.250:41352/ . This burdock database integrates molecular and chemical data to provide a comprehensive information and analysis platform for interested researchers and can be of immense help to the cultivation, breeding, and molecular pharmacognosy research of burdock.

Refined revealing the chain path of multiple ecosystem services under diverse environmental factor gradients.

A fragile karst ecosystem presents ecosystem services affected by the environment and interactions between ecosystem services. However, the ecosystem in the karst area is characterized by low environmental capacity and low resistance to force disturbance. Current research mainly focuses on the trade-off/synergy of ecosystem services in the karst area yet it lacks inductive analysis of the multiple chain path among ecosystem services. This paper quantitatively identified dominant factors influencing spatial differentiation of surface runoff, soil moisture, sediment yield, and net primary productivity (NPP) and determined the chain path. The chain paths of surface runoff-soil moisture-NPP and NPP-surface runoff-sediment yield were analyzed. The results showed that land use and soil type were the dominant factors, and chain effects of ecosystem services were diverse under the various dominant factor gradients. The mediation effects of paddy soil (97.21 %) and mountain meadow soil (55.56 %) were high, and surface runoff had a greater impact on NPP by affecting soil moisture. Among the diverse land use types, the mediation effect of surface runoff on NPP affecting sediment yield varied greatly (from 5 to 100 %). In addition, its variation trend was consistent with that of the soil moisture as the mediation variable. The mediation effect of surface runoff on construction land was the highest (99.43 %). This study provides the scientific basis for selecting more effective water and soil conservation measures by analyzing the chain relationships of multiple ecosystem services under different environmental factor gradients.

TEMPO mediated oxidative annulation of aryl methyl ketones with amines/ammonium acetate for imidazole synthesis.

A facile synthesis of 1H-imidazoles by direct oxidative annulation of aryl methyl ketones and primary amines has been developed in the presence of TEMPO under weakly acidic conditions. By replacing amines with ammonium acetate, 2H-imidazole skeletons were achieved for the first time from ketones. Substrates containing various functional groups, such as alkyl, aryl, naphthyl, halogen (F, Cl, Br, I), nitro, trifluoromethyl, sulfonyl ester, furyl, thienyl, and pyridyl groups, were readily transformed into the desired products. The application potential of this method was verified by the scale-up synthesis and Sonogashira coupling functionalization of imidazoles. Mechanistically, the α-TEMPO-enamine adduct may serve as the key reaction intermediate.

Oxidation of active cysteines mediates protein aggregation of S10R, the cataract-associated mutant of mouse GammaB-crystallin.

The Ser10 to Arg mutation in mouse γB-crystallin (MGB) has been associated with protein aggregation, dense nuclear opacity, and the degeneration of fiber cells in the lens core. Overexpression of the gap junction protein, connexin 46 (Cx46), was found to suppress the nuclear opacity and restore normal cell-cell contact. However, the molecular basis for the protein aggregation and related downstream effects were not evident from these studies. Here, we provide a comparison of the structures and solution properties of wild type MGB and the S10R mutant in vitro and show that, even though the mutation does not directly involve cysteine residues, some cysteines in the mutant protein are activated, leading to the enhanced formation of intermolecular disulfide-crosslinked protein aggregates relative to the wild-type. This occurs even as the protein structure is essentially unaltered. Thus, the primary event is enhanced protein aggregation due to the disulfide crosslinking of the mutant protein. We suggest that these aggregates eventually get deposited on fiber cell membranes. Since the gap junction protein, Cx46 is involved in the transport of reduced glutathione, we posit that these deposits interfere in Cx46-mediated glutathione transport and facilitate the oxidative stress-mediated downstream changes. Overexpression of Cx46 suppresses such oxidative aggregation. These studies provide a plausible explanation for the protein aggregation and other changes that accompany this mutation. If indeed cysteine oxidation is the primary event for protein aggregation also in vivo, then the S10R mutant mouse, which is currently available, could serve as a viable animal model for human age-onset cataract.

Involvement of DR→mPFC 5-HTergic neural projections in changes of social exploration behaviors caused by adult chronic social isolation in mice.

Social contacts play an important role in the development and survival of social animals. Social isolation (SI) at adolescence often induces abnormalities in many kinds of behaviors. This study assessed whether five weeks of continuous SI at adulthood could alter social behaviors and whether dorsal raphe nucleus (DR) to medial prefrontal cortex (mPFC) 5-HT neural projections were involved in this alteration in C57BL/6J adult male mice. The present study found that five weeks chronic social isolation (CSI) at adulthood increased mounting and sniffing behaviors in resident-intruder test, and lengthened duration staying in interaction zone of stranger cage in the three-chamber social preference test. CSI also reduced the release of 5-HT in the mPFC detected by 5-HT 1.0 sensor and measured by in vivo fiber photometry test. Meanwhile, the c-Fos expression indicated that CSI reduced the activity of serotonergic neurons. Chemogenetic activation of DR-mPFC 5-HTergic projection reduced sniffing of CSI mice in the resident-intruder test, but didn't significantly affect mounting behavior. It also decreased the interaction time during the three-chamber social preference test. Thus, 5-HT neural projections from the DR to the mPFC are involved in changes of social exploration behaviors induced by CSI at adulthood.

Involvement of the dopamine system in paternal behavior induced by repeated pup exposure in virgin male ICR mice.

Like mothers, fathers play a vital role in the development of the brain and behavior of offspring in mammals with biparental care. Unlike mothers, fathers do not experience the physiological processes of pregnancy, parturition, or lactation before their first contact with offspring. Whether pup exposure can induce the onset of paternal behavior and the underlying neural mechanisms remains unclear. By using Slc:ICR male mice exhibiting maternal-like parental care, the present study found that repeated exposure to pups for six days significantly increased the total duration of paternal behavior and shortened the latency to retrieve and care for pups. Repeated pup exposure increased c-Fos-positive neurons and the levels of dopamine- and TH-positive neurons in the nucleus accumbens (NAc). In addition, inhibition of dopamine projections from the ventral tegmental area to the NAc using chemogenetic methods reduced paternal care induced by repeated pup exposure. In conclusion, paternal behavior in virgin male ICR mice can be initiated by repeated pup exposure via sensitization, and the dopamine system may be involved in this process.

CRF-CRFR1 system within the dorsal medial prefrontal cortex are involved in consolation deficits under acute restraint stress in mandarin voles.

Consolation is a complex empathic behavior that has recently been observed in some socially living rodents. Despite the growing body of literature suggesting that stress affects some simple form of empathy, the relationship between stress and consolation remains largely understudied. Using monogamous mandarin voles, we found that an acute restraint stress exposure significantly reduced consolation-like behaviors and induced anxiety-like behaviors. Along with these behavioral changes, corticotropin-releasing factor (CRF) and CRF receptor 1 (CRFR1) neurons were activated within the anterior cingulate cortex (ACC) and prelimbic cortex (PrL) but not within the infralimbic cortex (IL). Chemogenetic activation of CRF neurons in the ACC and PrL, recaptured acute stress-induced behavioral dysfunctions. We further observed that intracellular PKA and PKC signaling pathways mediate CRF-induced behavioral dysfunctions, but they work in a regional-specific, sex-biased manner. Together, these results suggest that the local CRF-CRFR1 system within the ACC and PrL is involved in the consolation deficits and anxiety induced by acute stress.

Paraventricular Nucleus Oxytocin Subsystems Promote Active Paternal Behaviors in Mandarin Voles.

Paternal care plays a critical role in the development of brain and behaviors in offspring in monogamous species. However, the neurobiological mechanisms, especially the neuronal circuity, underlying paternal care is largely unknown. Using socially monogamous male mandarin voles (Microtus mandarinus) with high levels of paternal care, we found that paraventricular nucleus of the hypothalamus (PVN) to ventral tegmental area (VTA) or nucleus accumbens (NAc) oxytocin (OT) neurons are activated during paternal care. Chemogenetic activation/inhibition of the PVN OT projection to VTA promoted/decreased paternal care, respectively. Chemogenetic inhibition of the PVN to VTA OT pathway reduced dopamine (DA) release in the NAc of male mandarin voles during licking and grooming of pups as revealed by in vivo fiber photometry. Optogenetic activation/inhibition of the VTA to NAc DA pathway possibly enhanced/suppressed paternal behaviors, respectively. Furthermore, chemogenetic activation/inhibition of PVN to NAc OT circuit enhanced/inhibited paternal care. This finding is a first step toward delineating the neuronal circuity underlying paternal care and may have implications for treating abnormalities in paternal care associated with paternal postpartum depression or paternal abuse.SIGNIFICANCE STATEMENT Paternal behavior is essential for offspring survival and development in some mammalian species. However, the circuit mechanisms underlying the paternal brain are poorly understood. We show that manipulation of paraventricular nucleus of the hypothalamus (PVN) to ventral tegmental area (VTA) oxytocin (OT) projections as well as VTA to nucleus accumbens (NAc) DA projections promote paternal behaviors. Inhibition the PVN to VTA OT pathway reduces DA release in the NAc during pup licking and grooming. PVN to NAc OT circuit is also essential for paternal behaviors. Our findings identify two new neural circuits that modulate paternal behaviors.

Dorsal raphe nucleus to anterior cingulate cortex 5-HTergic neural circuit modulates consolation and sociability.

Consolation is a common response to the distress of others in humans and some social animals, but the neural mechanisms underlying this behavior are not well characterized. By using socially monogamous mandarin voles, we found that optogenetic or chemogenetic inhibition of 5-HTergic neurons in the dorsal raphe nucleus (DR) or optogenetic inhibition of serotonin (5-HT) terminals in the anterior cingulate cortex (ACC) significantly decreased allogrooming time in the consolation test and reduced sociability in the three-chamber test. The release of 5-HT within the ACC and the activity of DR neurons were significantly increased during allogrooming, sniffing, and social approaching. Finally, we found that the activation of 5-HT1A receptors in the ACC was sufficient to reverse consolation and sociability deficits induced by the chemogenetic inhibition of 5-HTergic neurons in the DR. Our study provided the first direct evidence that DR-ACC 5-HTergic neural circuit is implicated in consolation-like behaviors and sociability.

Sex-Dependent Effects of Chronic Social Defeat on Emotional and Social Behaviors, and Parameters of Oxytocin and Vasopressin Systems in Mandarin Voles (Microtus mandarinus).

In the regulation of emotional and social behaviors, both oxytocin (OT) and vasopressin (AVP) are sex specific. Although significant sex differences have been reported in the context of behavioral and hormonal responses to social stress, such differences in response to chronic social defeat stress (CSDS) and the underlying neural mechanisms remain largely unknown. By investigating monogamous mandarin voles (Microtus mandarinus), CSDS was found to decrease the percentages of time spent in the central area of the open field, in the open arms of the elevated plus maze, as well as in the light area of the light and dark boxes in both male and female voles. CSDS also increased the observed level of social withdrawal in both sex groups. However, CSDS exposure increased the percentages of immobile time in both the tail suspension test and the forced swim test and reduced the locomotor activity in the open field (in females only). Along with these behavioral changes, the oxytocin receptor (OTR) levels in the nucleus accumbens (NAc) were significantly lower in CSDS-exposed voles of both sexes; however, in males, the levels of OTR in the paraventricular nucleus (PVN) were reduced. CSDS-exposed males showed lower levels of V1aR in the NAc than CSDS-exposed females. Furthermore, induced by a single social defeat event, CSDS reduced c-Fos and OT double labeling in the PVN of females but increased c-Fos and AVP double-labeled neurons in the PVN of males exposed to a single social defeat event. Collectively, the present study indicates that OT and AVP systems may play important regulatory roles in the sex differences of behavioral performances in response to CSDS. These findings suggest mandarin voles as a useful animal model for studying sex-specific behavioral performance and the underlying neurobiological mechanisms of stress-related mental disorders in preclinical studies.