Probes for INS

Long-noncoding RNAs (lncRNAs) have numerous biological functions controlling cell differentiation and tissue development. The knowledge about the role of lncRNAs in human lungs remains limited. Here we found the regulatory role of the terminal differentiation-induced lncRNA (TINCR) in bronchial cell differentiation. RNA in situ hybridization revealed that TINCR was mainly expressed in bronchial epithelial cells in normal human lung. We performed RNA sequencing analysis of normal human bronchial epithelial cells (NHBECs) with or without TINCR inhibition and found the differential expression of 603 genes, which were enriched for cell adhesion and migration, wound healing, extracellular matrix organization, tissue development and differentiation. To investigate the role of TINCR in the differentiation of NHBECs, we employed air-liquid interface culture and 3D organoid formation assay. TINCR was upregulated during differentiation, loss of TINCR significantly induced an early basal-like cell phenotype (TP63) and a ciliated cell differentiation (FOXJ1) in late phase and TINCR overexpression suppressed basal cell phenotype and the differentiation toward to ciliated cells. Critical regulators of differentiation such as SOX2 and NOTCH genes (NOTCH1, HES1, and JAG1) were significantly upregulated by TINCR inhibition and downregulated by TINCR overexpression. RNA immunoprecipitation assay revealed that TINCR was required for the direct bindings of Staufen1 protein to SOX2, HES1, and JAG1 mRNA. Loss of Staufen1 induced TP63, SOX2, NOTCH1, HES1, and JAG1 mRNA expressions, which TINCR overexpression suppressed partially. In conclusion, TINCR is a novel regular of bronchial cell differentiation, affecting downstream regulators such as SOX2 and NOTCH genes, potentially in coordination with Staufen1.

Erythrocyte mass contributes to maintaining systemic oxygen delivery and blood viscosity, with the latter being one of the determinants of blood pressure. However, the physiological response to blood pressure changes under anaemic conditions remain unknown. We show that anaemia decreases blood pressure in human patients and mouse models. Analyses of pathways related to blood pressure regulation demonstrate that anaemia enhances the expression of the gene encoding the vasopressor substance renin in kidneys. Although kidney juxtaglomerular cells are known to continuously produce renin, renal interstitial fibroblasts are identified in the present study as a novel site of renin induction under anaemic hypotensive conditions in mice and rats. Notably, some renal interstitial fibroblasts are found to simultaneously express renin and the erythroid growth factor erythropoietin in the anaemic mouse kidney. Antihypertensive agents but not hypoxic stimuli induced interstitial renin expression, suggesting that blood pressure reduction triggers interstitial renin induction in anaemic mice. The interstitial renin expression was also detected in injured fibrotic kidneys of the mouse and human, and the renin-expressing interstitial cells in murine fibrotic kidneys were identified as myofibroblasts originating from renal interstitial fibroblasts. Since the elevated expression levels of renin in fibrotic kidneys along with progression of renal fibrosis were well correlated to the systemic blood pressure increase, the renal interstitial renin production seemed to affect systemic blood pressure. Renal interstitial fibroblasts function as central controllers of systemic oxygen delivery by producing both renin and erythropoietin. Grants-in-Aid from Japan Society for the Promotion of Science (JSPS) KAKENHI (17K19680, 15H04691, and 26111002) and the Takeda Science Foundation.

HBZ-ISH was performed to detect HTLV-1 in tissue specimens from 21 HTLV-1–seropositive cases with CHL-like morphology (supplemental Table 1). Three cases were nonevaluable due to negativity for the positive control (_PPIB_). HRS-like cells were negative for HBZ-ISH in 10 cases. Among them, 3 cases showed HRS-like cells positive for EBER-ISH and/or PAX5 as well as monoclonal TCR-γ chain gene rearrangement or loss of pan-T-cell antigens in the background cells, corresponding to the currently recognized pathological features of Hodgkin-like ATLL.16,17  Thus, 8 cases, including a recently described case (case 1)19  with a positive HBZ-ISH signal in HRS-like cells, were considered to be ATLL with HTLV-1–infected HRS-like cells. The clinical characteristics of these cases are shown in Table 1. The median age of the patients (4 males and 4 females) was 73 years (range, 55-81 years). All patients showed nodal or mediastinal lesions. Five patients (63%) were in an advanced stage of disease (Ann Arbor stage III or IV) at presentation. Bone marrow and hepatosplenic involvement was observed in 3 and 2 cases, respectively, but no other extranodal lesions were present in any of the cases. All patients except for case 6, who was treated with palliative care because of the co-occurrence of severe liver cirrhosis, received systemic combination chemotherapy. Two patients (cases 1 and 3) were mainly treated with ABVD, a standard therapy for CHL, and 5 patients were treated with a combination chemotherapy regimen such as CHOP. All cases, with enough follow-up period, treated with chemotherapy achieved complete remission, except for case 4, but a longer remission (>2 years) was achieved in 2 patients treated with CHOP. One patient (case 4) had been followed up for chronic-type ATLL before lymph node biopsy. This patient had very high serum levels of soluble interleukin-2 receptor, a prognostic biomarker for poor outcome,8  was refractory to systemic chemotherapy, and died 3 months after diagnosis (Table 1).

Rationale: Interstitial mesenchymal cells maintain alveolar epithelial (AT) cells (AT1 and AT2) homeostasis in health and disease. Human LAM is characterized by enlarged airspaces, cystic destruction of the lung parenchyma, and lung function decline, leading to respiratory failure. The exact mechanism behind the alveolar remodeling in LAM lung is still unknown. In the genetic mouse model of LAM, characterized by progressive enlargement of airspaces and female-specific lung function decline, we found that lung mesenchymal cells affect AT1/AT2 cell fitness through up-regulation of WNT signaling. We also discovered that genetic inhibition of the WNT pathway in mouse lung mesenchyme restored the observed disease phenotype. We utilized immunofluorescent histochemistry on the lung sections to study the differences in the architecture and cellular composition of the alveolar septal walls in human control and LAM lungs and found an increased number of transitional AT2/AT1 cells. We propose that LAM mesenchyme dysregulates the proliferation of the neighboring AT2 cells, which results in the abnormal architecture of LAM lung parenchyma.Methods: To study mesenchymal-epithelial interactions ex vivo we used 3D co-cultures of mesenchymal cells, isolated from multiple age-matched LAM and control human female lung, with primary AT2 cells isolated from control human female lungs. Results: LAM lung-derived mesenchyme supported increased colony-forming-efficiency (CFE), size, and structural complexity of AT2 organoids, compared to the control ones. LAM lung-derived mesenchymal support cells expressed increased levels of estrogen alphaencoding gene ESR1, as well as pro-mitotic gene WNT2. Using RNA-scope, we found the upregulation of the WNT pathway in the AT2 cells and in the LAM cells compared to the controls. In agreement with these findings, the CFE of LAM-based organoids was increased by estrogen stimulation and decreased by WNT-pathway inhibitors. Notably, control-lung-based organoids had simple monolayer organization, while LAM-based organoids formed highly organized and compartmentalized structures, composed of both AT2 and AT1 cells. LAM-based organoids also exhibited robust staining for AT1 cell marker – AQP5, specifically in the core of the organoid spheres, while AQP5+ cells lined up the walls of the internal organoid compartments. Conclusion: Our data demonstrate that upregulation of mTORC1-WNT signaling drives cystic airspace enlargement due to chronic activation of LAM cells and alveolar epithelial cells, promote abnormal epithelial-mesenchymal crosstalk, which affects the fitness of surrounding AT2 cells and potentially contributes to the cystic remodeling in the LAM lung through WNT pathway dysregulation.

The Zika virus (ZIKV) represents an important global health threat due to its unusual association with congenital Zika syndrome. ZIKV strains are phylogenetically grouped into the African and Asian lineages. However, the viral determinants underlying the phenotypic differences between the lineages remain unknown. Here, multiple sequence alignment revealed a highly conserved residue at position 21 of the premembrane (prM) protein, which is glutamic acid and lysine in the Asian and African lineages, respectively. Using reverse genetics, we generated a recombinant virus carrying an E21K mutation based on the genomic backbone of the Asian lineage strain FSS13025 (termed E21K). The E21K mutation significantly increased viral replication in multiple neural cell lines with a higher ratio of M to prM production. Animal studies showed E21K exhibited increased neurovirulence in suckling mice, leading to more severe defects in mouse brains by causing more neural cell death and destruction of hippocampus integrity. Moreover, the E21K substitution enhanced neuroinvasiveness in interferon alpha/beta (IFN-α/β) receptor knockout mice, as indicated by the increased mortality, and enhanced replication in mouse brains. The global transcriptional analysis showed E21K infection profoundly altered neuron development networks and induced stronger antiviral immune response than wild type (WT) in both neural cells and mouse brains. More importantly, the reverse K21E mutation based on the genomic backbone of the African strain MR766 caused less mouse neurovirulence. Overall, our findings support the 21st residue of prM functions as a determinant for neurovirulence and neuroinvasiveness of the African lineage of ZIKV. IMPORTANCE The suspected link of Zika virus (ZIKV) to birth defects led the World Health Organization to declare ZIKV a Public Health Emergency of International Concern. ZIKV has been identified to have two dominant phylogenetic lineages, African and Asian. Significant differences exist between the two lineages in terms of neurovirulence and neuroinvasiveness in mice. However, the viral determinants underlying the phenotypic differences are still unknown. Here, combining reverse genetics, animal studies, and global transcriptional analysis, we provide evidence that a single E21K mutation of prM confers to the Asian lineage strain FSS130125 significantly enhanced replication in neural cell lines and more neurovirulent and neuroinvasiveness phenotypes in mice. Our findings support that the highly conserved residue at position 21 of prM functions as a determinant of neurovirulence and neuroinvasiveness of the African lineage of ZIKV in mice.

Background: HIV-specific chimeric antigen receptor T (CAR T) cells are being developed as a potential approach towards curing HIV infection. During infection, HIV replication is concentrated in B cell follicles, and viral reservoirs such as B cell follicles are a significant barrier to an HIV cure. We developed HIV-specific CAR T cells expressing the follicular homing receptor CXCR5 (CAR/CXCR5 T cells) to target follicular HIV reservoirs. We hypothesized after infusion of CAR/CXCR5 T cells in humanized HIV-infected DRAGA mice, CAR/CXCR5 T cells would accumulate in lymphoid follicles, make direct contact with HIV+ cells, lead to reductions in HIV viral loads, and preserve human CD4 T cells. Methods: Fourteen female humanized DRAGA mice were included in this study. Twelve mice were infected with 10 000 TCID50 of HIV-1 BaL. Levels of HIV-1 plasma viral loads and CD4 T cells were monitored using qRT-PCR and flow cytometry. Two spleens from uninfected mice were used to produce transduced CAR/CXCR5 T cells and transduced cell products (2×105 cells/gram) were infused in six HIV-infected mice. RNAscope combined with immunohistochemistry was used to visualize locations and quantities of CAR/CXCR5 T cells and HIV vRNA+ cells in lymphoid tissues. Results: All mice were HIV-1 detectable nbefore infusion of CAR/CXCR5 T cells. High levels of CAR/CXCR5 T cells and HIV vRNA+ cells were detected at 6 days post-infusion in lymphoid tissues. Many CAR/CXCR5 T cells were found in direct contact with HIV vRNA+ cells. However, many CAR/CXCR5 T cells, presumably CD4+ cells, were HIV vRNA+ and likely spreading infection. No differences in HIV plasma viral loads or CD4 T cell counts were observed between control and treated animals. Conclusions: These studies support the use of the HIV-infected DRAGA mouse model for HIV cure research studies. Using this model, we showed CAR/CXCR5 T cells accumulate in follicle-like structures with HIV vRNA+ cells and come in contact with vRNA+ cells. The simultaneous detection of CAR T cells with high levels of HIV vRNA+ cells indicates the need for HIV-resistant CAR T cells. These preliminary findings demonstrate the HIV-infected DRAGA mouse model is extremely valuable for evaluating HIV cure approaches.

Transthyretin (TTR) distributes thyroxine in the cerebrospinal fluid of mammals. Choroid plexus epithelial cells produce and secrete TTR, and were long recognized as the only CNS source of TTR. However, research over the last years has reported neuronal-specific expression as well, but without a clear function. Recently, we found Ttr transcripts in cells of the adult mouse subventricular zone (SVZ), the largest neural stem cell (NSC) region, but the protein was undetectable. We therefore investigated in more detail what role TTR might play in the SVZ, and when. We mapped temporal-spatial Ttr expression by re-analysing publicly available single-cell RNA-Seq data obtained from dissected mouse SVZs at E14-E17-P2-P7-P20-P61. We observed a peak in Ttr expression in NSCs, neural progenitors and differentiating cells at postnatal day 7 (P7). That is one week prior to when thyroxine serum levels peak and T3 activates SVZ-NSCs that start generating neurons and glia at a constant rate. RNAscope on P7 brain sections confirmed that few Ttr transcripts are present in a many SVZ-progenitors, oligodendrocyte precursors and neuroblasts. Unexpectedly though, no protein was detectable using commercially available antibodies, signal amplification and appropriate controls. This might suggest TTR is rapidly secreted to affect nearby cells. To test this hypothesis, we prepared neurospheres from dissected SVZ-progenitors at P7. After 7 days of proliferation, cells were dissociated, and allowed to differentiate for 1 or 5 days. In parallel with controls, we treated them once at day 0 of differentiation with a low (2.5 µg/ml) or a high dose (25 µg/ml) of human recombinant TTR, or with 5 nM T3. Low TTR doses reduced cell mitosis at day 1, as did T3. After 5 days, we counted a 30% lower proportion of differentiated neuroblasts with the highest TTR dose. That proportion had dropped 3-fold in the presence of T3. Proportions of oligodendroglia after 5 days of differentiation were only significantly higher in T3 conditions. As a result, the neuron/glia balance shifted in favour of oligodendrogenesis under T3, and borderline-significantly following high TTR doses. Altogether, the murine SVZ represents a novel region containing cells that express Ttr, with a peak at P7, despite seeming absence of the protein itself, precluding deducing its exact role. Single-cell RNA-Seq on treated neurospheres could reveal how exogenous TTR affects intracellular pathways, and whether its action is TH-dependent or not. This can help unravelling the pathophysiology of familial amyloid polyneuropathy, in which misfolded TTR proteins cause neurodegeneration.

Following tissue injury, latent sensitization (LS) of nociceptive signaling can persist indefinitely, kept in remission by compensatory µ-opioid receptor constitutive activity (MORCA) in the dorsal horn of the spinal cord. To demonstrate LS, we conducted plantar incision in mice and then waited 3-4 weeks for hypersensitivity to resolve. At this time (remission), systemic administration of the opioid receptor antagonist/inverse agonist naltrexone reinstated mechanical and heat hypersensitivity. We first tested the hypothesis that LS extends to serotonergic neurons in the rostral ventral medulla (RVM) that convey pronociceptive input to the spinal cord. We report that in male and female mice, hypersensitivity was accompanied by increased Fos expression in serotonergic neurons of the RVM, abolished upon chemogenetic inhibition of RVM 5-HT neurons, and blocked by intrathecal injection of the 5-HT3R antagonist ondansetron; the 5-HT2AR antagonist MDL-11,939 had no effect. Second, to test for MORCA, we microinjected the MOR inverse agonist CTAP and/or neutral opioid receptor antagonist 6β-naltrexol. Intra-RVM CTAP produced mechanical hypersensitivity at both hindpaws. 6β-naltrexol had no effect by itself, but blocked CTAP-induced hypersensitivity. This indicates that MORCA, rather than an opioid ligand-dependent mechanism, maintains LS in remission. We conclude that incision establishes LS in descending RVM 5-HT neurons that drives pronociceptive 5-HT3R signaling in the dorsal horn, and this LS is tonically opposed by MORCA in the RVM. The 5-HT3 receptor is a promising therapeutic target for the development of drugs to prevent the transition from acute to chronic post-surgical pain.Significance statementSurgery leads to latent pain sensitization and a compensatory state of endogenous pain control that is maintained long after tissue healing. Here we show that either chemogenetic inhibition of serotonergic neuron activity in the rostral ventromedial medulla (RVM), or pharmacological inhibition of 5-HT3 receptor signaling at the spinal cord blocks behavioral signs of post-surgical latent sensitization. We conclude that µ-opioid receptor constitutive activity (MORCA) in the RVM opposes descending serotonergic facilitation of LS, and that the 5-HT3 receptor is a promising therapeutic target for the development of drugs to prevent the transition from acute to chronic post-surgical pain.

Lower urinary tract or voiding disorders are prevalent across all ages and affect over 40% of adults over 40 years old leading to decreased quality of life and high healthcare costs. The pontine micturition center (PMC; ie, Barrington's nucleus) contains a large population of neurons that localize the stress-related neuropeptide, corticotropin-releasing hormone (CRH) and project to neurons in the spinal cord to regulate micturition. How the PMC and CRH-expressing neurons in the PMC control volitional micturition is of critical importance for human voiding disorders. To investigate the specific role of CRH in the PMC, neurons in the PMC expressing CRH were optogenetically activated during in vivo cystometry in unanesthetized mice of either sex. Optogenetic activation of CRH-PMC neurons led to increased intermicturition interval and voided volume, similar to the altered voiding phenotype produced by social stress. Female mice showed a significantly more pronounced phenotype change compared with male mice. These effects were eliminated by CRH-receptor 1 antagonist pretreatment. Optogenetic inhibition of CRH-PMC neurons led to an altered voiding phenotype characterized by more frequent voids and smaller voided volumes. Lastly, in a cyclophosphamide cystitis model of bladder overactivity, optogenetic activation of CRH-PMC neurons returned the voiding pattern to normal. Collectively, our findings demonstrate that CRH from PMC spinal-projecting neurons has an inhibitory function on micturition and is a potential therapeutic target for human disease states such as voiding postponement, urinary retention, and under- or over-active bladder.SIGNIFICANCE STATEMENT:The pontine micturition center (PMC), which is a major regulator of volitional micturition, is neurochemically heterogenous and excitatory neurotransmission derived from PMC neurons is thought to mediate the micturition reflex. In the present study, using optogenetic manipulation of CRH-containing neurons in double transgenic mice, we demonstrate that CRH, which is prominent in PMC-spinal projections, has an inhibitory function on volitional micturition. Moreover, engaging this inhibitory function of CRH can ameliorate bladder hyperexcitability induced by cyclophosphamide in a model of cystitis. The data underscore CRH as a novel target for the treatment of voiding dysfunctions, which are highly prevalent disease processes in children and adults.

FGFR1 amplification, but not overexpression, has been related to adverse prognosis in hormone-positive breast cancer (HRPBC). Whether FGFR1 overexpression and amplification are correlated, what is their distribution among luminal A or B HRPBC, and if there is a potential different prognostic role for amplification and overexpression are currently unknown features. The role of FGFR1 inhibitors in HRPBC is also unclear. FGFR1 amplification (FISH) and overexpression (RNAscope) were investigated in a N = 251 HRPBC patients cohort and the METABRIC cohort; effects on survival and FISH-RNAscope concordance were determined. We generated hormonal deprivation resistant (LTED-R) and FGFR1-overexpressing cell line variants of the ER+ MCF7 and T47-D and the ER+, FGFR1-amplified HCC1428 cell lines. The role of ER, CDK4/6, and/or FGFR1 blockade alone or in combinations in Rb phosphorylation, cell cycle, and survival were studied. FGFR1 overexpression and amplification was non-concordant in > 20% of the patients, but both were associated to a similar relapse risk (~ 2.5-fold; P < 0.05). FGFR1 amplification or overexpression occurred regardless of the luminal subtype, but the incidence was higher in luminal B (16.3%) than A (6.6%) tumors; P < 0.05. The Kappa index for overexpression and amplification was 0.69 (P < 0.001). Twenty-four per cent of the patients showed either amplification and/or overexpression of FGFR1, what was associated to a hazard ratio for relapse of 2.6 (95% CI 1.44-4.62, P < 0.001). In vitro, hormonal deprivation led to FGFR1 overexpression. Primary FGFR1 amplification, engineered mRNA overexpression, or LTED-R-acquired FGFR1 overexpression led to resistance against hormonotherapy alone or in combination with the CDK4/6 inhibitor palbociclib. Blocking FGFR1 with the kinase-inhibitor rogaratinib led to suppression of Rb phosphorylation, abrogation of the cell cycle, and resistance-reversion in all FGFR1 models. FGFR1 amplification and overexpression are associated to similar adverse prognosis in hormone-positive breast cancer. Capturing all the patients with adverse prognosis-linked FGFR1 aberrations requires assessing both features. Hormonal deprivation leads to FGFR1 overexpression, and FGFR1 overexpression and/or amplification are associated with resistance to hormonal monotherapy or in combination with palbociclib. Both resistances are reverted with triple ER, CDK4/6, and FGFR1 blockade.

Sarcopenia, the age-associated decline in skeletal muscle mass and strength, has long been considered a disease of muscle only, but accumulating evidence suggests that sarcopenia could originate from the neural components controlling muscles. To identify early molecular changes in nerves that may drive sarcopenia initiation, we performed a longitudinal transcriptomic analysis of the sciatic nerve, which governs lower limb muscles, in aging mice.Sciatic nerve and gastrocnemius muscle were obtained from female C57BL/6JN mice aged 5, 18, 21 and 24 months old (n = 6 per age group). Sciatic nerve RNA was extracted and underwent RNA sequencing (RNA-seq). Differentially expressed genes (DEGs) were validated using quantitative reverse transcription PCR (qRT-PCR). Functional enrichment analysis of clusters of genes associated with patterns of gene expression across age groups (adjusted P-value < 0.05, likelihood ratio test [LRT]) was performed. Pathological skeletal muscle aging was confirmed between 21 and 24 months by a combination of molecular and pathological biomarkers. Myofiber denervation was confirmed with qRT-PCR of Chrnd, Chrng, Myog, Runx1 and Gadd45ɑ in gastrocnemius muscle. Changes in muscle mass, cross-sectional myofiber size and percentage of fibres with centralized nuclei were analysed in a separate cohort of mice from the same colony (n = 4-6 per age group).We detected 51 significant DEGs in sciatic nerve of 18-month-old mice compared with 5-month-old mice (absolute value of fold change > 2; false discovery rate [FDR] < 0.05). Up-regulated DEGs included Dbp (log2 fold change [LFC] = 2.63, FDR < 0.001) and Lmod2 (LFC = 7.52, FDR = 0.001). Down-regulated DEGs included Cdh6 (LFC = -21.38, FDR < 0.001) and Gbp1 (LFC = -21.78, FDR < 0.001). We validated RNA-seq findings with qRT-PCR of various up- and down-regulated genes including Dbp and Cdh6. Up-regulated genes (FDR < 0.1) were associated with the AMP-activated protein kinase signalling pathway (FDR = 0.02) and circadian rhythm (FDR = 0.02), whereas down-regulated DEGs were associated with biosynthesis and metabolic pathways (FDR < 0.05). We identified seven significant clusters of genes (FDR < 0.05, LRT) with similar expression patterns across groups. Functional enrichment analysis of these clusters revealed biological processes that may be implicated in age-related changes in skeletal muscles and/or sarcopenia initiation including extracellular matrix organization and an immune response (FDR < 0.05).Gene expression changes in mouse peripheral nerve were detected prior to disturbances in myofiber innervation and sarcopenia onset. These early molecular changes we report shed a new light on biological processes that may be implicated in sarcopenia initiation and pathogenesis. Future studies are warranted to confirm the disease modifying and/or biomarker potential of the key changes we report here.

Stress responses are believed to involve corticotropin releasing factor (CRF), its two cognate receptors (CRF1 and CRF2), and the CRF-binding protein (CRFBP). Whereas decades of research has focused on CRF1, the role of CRF2 in the central nervous system (CNS) has not been thoroughly investigated. We have previously reported that CRF2, interacting with a C terminal fragment of CRFBP, CRFBP(10kD), may have a role in the modulation of neuronal activity. However, the mechanism by which CRF interacts with CRFBP(10kD) and CRF2 has not been fully elucidated due to the lack of useful chemical tools to probe CRFBP.We miniaturized a cell-based assay, where CRFBP(10kD) is fused as a chimera with CRF2, and performed a high-throughput screen (HTS) of 350,000 small molecules to find negative allosteric modulators (NAMs) of the CRFBP(10kD)-CRF2 complex. Hits were confirmed by evaluating activity toward parental HEK293 cells, toward CRF2 in the absence of CRFBP(10kD), and toward CRF1 in vitro. Hits were further characterized in ex vivo electrophysiology assays that target: 1) the CRF1+ neurons in the central nucleus of the amygdala (CeA) of CRF1:GFP mice that express GFP under the CRF1 promoter, and 2) the CRF-induced potentiation of N-methyl-D-aspartic acid receptor (NMDAR)-mediated synaptic transmission in dopamine neurons in the ventral tegmental area (VTA).We found that CRFBP(10kD) potentiates CRF-intracellular Ca2+ release specifically via CRF2, indicating that CRFBP may possess excitatory roles in addition to the inhibitory role established by the N-terminal fragment of CRFBP, CRFBP(27kD). We identified novel small molecule CRFBP-CRF2 NAMs that do not alter the CRF1-mediated effects of exogenous CRF but blunt CRF-induced potentiation of NMDAR-mediated synaptic transmission in dopamine neurons in the VTA, an effect mediated by CRF2 and CRFBP.These results provide the first evidence of specific roles for CRF2 and CRFBP(10kD) in the modulation of neuronal activity and suggest that CRFBP(10kD)-CRF2 NAMs can be further developed for the treatment of stress-related disorders including alcohol and substance use disorders.