Biomedical subjects

Dongsheng Zhang

Publications and source records attributed to Dongsheng Zhang.

At least 19 recordsLinked to original sources

PubMed2006

c-Fos facilitates the acquisition and extinction of cocaine-induced persistent changes.

Development of drug addiction involves persistent neurobiological changes. The dopamine D1 receptor is involved in mediating cocaine-induced neuroadaptation, yet the underlying intracellular mechanisms remain unclear. We examined a potential role of the immediate early gene Fos, which is robustly and rapidly induced by cocaine via D1 receptors, in mediating cocaine-induced persistent neurobiological changes by creating and analyzing a mouse in which Fos is primarily disrupted in D1 receptor-expressing neurons in the brain. We show that the expression levels of several transcription factors, neurotransmitter receptors, and intracellular signaling molecules induced by repeated cocaine administration are altered in Fos-deficient brains. Dendritic remodeling of medium spiny neurons induced by repeated exposure to cocaine is blunted in the mutant mice. The mutant mice exhibit attenuated behavioral sensitization after repeated exposure to cocaine and more persistent memory of cocaine-induced conditioned place preference. Our findings indicate that c-Fos produced in D1 receptor-expressing neurons integrates mechanisms to facilitate both the acquisition and extinction of cocaine-induced persistent changes.

Animals↗

PubMed2006

Evidence for ischemia induced host-derived bone marrow cell mobilization into cardiac allografts.

Mobilized bone marrow stem cells (BMSC) exhibit high degree of plasticity and participate in the repair process in the event of myocardial damage. In this study, we verified the proportional contribution of recipient BMSC in the repair process and identified their specific surface markers. Wild-type (WT) donor female heart was transplanted into abdominal cavity of male rat (Group I). In some of recipient animals, infarction was created by LAD occlusion (Group II). Two weeks later, transplanted female hearts were harvested for histological analysis of the mobilized cells. C-kit, CD31, Ki67 and Y-chromosome were used as markers to identify mobilized cells in the female hearts. Y-chromosome positive cells were found in the donor female cardiac allografts. Acute myocardial infarction (AMI) of recipient heart induced migration of progenitor cells into the lesions of chronic rejection in the allograft. Donor ventricular mass reduction was more pronounced in Group I. Endothelial progenitor cells induced by AMI from male recipient extensively migrated into the cardiac allograft. SDF-1 mRNA levels significantly increased (peak level at 24 h after AMI) in recipient heart. CXCR4 was strongly expressed in the transplanted hearts around the perivascular area. Spontaneous mobilization of hematopoietic progenitor cells (HPCs) occurred in cardiac allografts after creating recipient heart AMI and was detectable until 2 weeks. These data suggests that CXCR4 overexpression enhances vascularization in the damaged myocardium and SDF-1/CXCR4 axis seems particularly important in progenitor cell chemotaxis, homing, engraftment and retention in damaged myocardium. In addition, BMSC attracted to the site of ischemic injury participate in cardiac repair.

Animals↗

PubMed2006

Cluster structure and corralling effect driven by interaction mismatch in two dimensional mixtures.

The formation of clusters with crystal-like order in two dimensions is studied using Monte Carlo simulations. We find that the necessary conditions to induce the formation of clusters of one component is to add a second component that has a larger size and that has a long-range soft repulsive interaction with its own kind but not with the other one. The clusters of the small particles are found to be surrounded by a network of quasi-one-dimensional arrangements of the larger particles. The degree of order of the clusters is found to depend on the concentration of the larger particles. The findings explain recent experimental observations on lipid-poloxamer mixtures and they provide guidelines for how to form ordered clusters of nanoparticles in two dimensions.

Journal Article↗

PubMed2006

Misexpression screen for genes altering the olfactory map in Drosophila.

Despite the identification of a number of guidance molecules, a comprehensive picture has yet to emerge to explain the precise anatomy of the olfactory map. From a misexpression screen of 1,515 P{GS} lines, we identified 23 genes that, when forcibly expressed in the olfactory receptor neurons, disrupted the stereotyped anatomy of the Drosophila antennal lobes. These genes, which have not been shown previously to control olfactory map development, encode novel proteins as well as proteins with known roles in axonal outgrowth and cytoskeletal remodeling. We analyzed Akap200, which encodes a Protein Kinase A-binding protein. Overexpression of Akap200 resulted in fusion of the glomeruli, while its loss resulted in misshapen and ectopic glomeruli. The requirement of Akap200 validates our screen as an effective approach for recovering genes controlling glomerular map patterning. Our finding of diverse classes of genes reveals the complexity of the mechanisms that underlie olfactory map development.

A Kinase Anchor Proteins↗

PubMed2006

Development of Lorentz force-type self-bearing motor for an alternative axial flow blood pump design.

A Lorentz force-type self-bearing motor was developed to provide delivery of both motoring torque and levitation force for an alternative axial flow blood pump design with an enclosed impeller. The axial flow pumps currently available introduce electromagnetic coupling from the motor's stator to the impeller by means of permanent magnets (PMs) embedded in the tips of the pump's blades. This design has distinct disadvantages, for example, pumping efficiency and electromagnetic coupling transmission are compromised by the constrained or poor geometry of the blades and limited pole width of the PMs, respectively. In this research, a Lorentz force-type self-bearing motor was developed. It is composed of (i) an eight-pole PM hollow-cylindrical rotor assembly supposedly to house and enclose the impeller of an axial flow blood pump, and (ii) a six-pole stator with two sets of copper wire and different winding configurations to provide the motoring torque and levitating force for the rotor assembly. MATLAB's xPC Target interface hardware was used as the rapid prototyping tool for the development of the controller for the self-bearing motor. Experimental results on a free/simply supported rotor assembly validated the design feasibility and control algorithm effectiveness in providing both the motoring torque and levitation force for the rotor. When levitated, a maximum orbital displacement of 0.3 mm corresponding to 1050 rpm of the rotor was measured by two eddy current probes placed in the orthogonal direction. This design has the advantage of eliminating the trade-off between motoring torques, levitating force, and pumping efficiency of previous studies. It also indicated the benefits of enclosed-impeller design as having good dynamic response, linearity, and better reliability. The nonmechanical contact feature between rotating and stationary parts will further reduce hemolysis and thromboembolitic tendencies in a typical blood pump application.

Biomedical Engineering↗

PubMed2006

[Preparation and characterization of magnetic nano-particles with radiofrequency-induced hyperthermia for cancer treatment].

Mn0.5Zn0.5Fe2O4 nano-particles were prepared by the chemical co-precipitation, their characteristics were observed with transmission electron microscope (TEM), X-ray diffractometer (XRD) and thermal analysis system, and etc. The temperature changes of the nano-particles of Mn0.5Zn0.5Fe2O4 and its magnetic fluid explored in radiofrequency(RF,200 KHz, 4 KW) were measured. The proliferation ratio of L929 cells cultured in soak of Mn0.5Zn0.5Fe2O4 nano-particles were observed. The experiment indicates that the magnetic particles were about 40 nm diameter in average, round, had strong magnetism, and were proved to be consistent with the standard data of chart of XRD. Its magnetic fluid exposed to RF could be heated up to temperature range from 40 degrees C to 51 degrees C due to the amount of the magnetic nano-particles and intensity of the alternating magnetic field. Magnetic nano-particles were found to have no obvious cytotoxicity to L929 cells.

Animals↗

PubMed2006

[Preparation and characterization of Mn-Zn ferrite oxygene nanoparticle for tumor thermotherapy].

With the sulfate as the materials and NaOH as precipitator, Mn(0.4)Zn(0.6)Fe2O4 nanoparticles were produced, which are proved to be spinel Mn-Zn ferrite analyzed by X-ray diffraction(XRD). Their shapes are approximately global examined by transmission electron microscopy(TEM) and their average diameter is 50 nm measured with image analysis-system. The Curie temperature was measured and in vitro heating test in a alternating magnetic field was carried out. The results show that the Curie temperature is 105. 407 degrees C, While its magnetic fluid could rise to 43 degrees C - 47 degrees C due to different concentration in a alternating magnetic field. The result provide theoretical and practical evidence to select an appropriate material and concentration for tumor

Electromagnetic Fields↗

PubMed2005

Immunization using autologous dendritic cells pulsed with the melanoma-associated antigen gp100-derived G280-9V peptide elicits CD8+ immunity.

PURPOSE: To determine the toxicity, maximal tolerated dose, and clinical and immunologic response to autologous dendritic cells pulsed with melanoma-associated antigen gp100-derived G280-9V peptide. PATIENTS AND METHODS: Twelve HLA-A*0201(+) patients with advanced melanoma were administered dendritic cells pulsed with G280-9V peptide. Cohorts of three patients were administered 5 x 10(6), 15 x 10(6), and 50 x 10(6) cells i.v. every 3 weeks for six doses according to a dose escalation scheme. Three additional patients were treated at the highest dose. No additional cytokines or therapies were coadministered. The immunogenicity of G280-9V-pulsed dendritic cells was measured by IFN-gamma ELISPOT assay, tetramer assay, and (51)Cr release assay comparing prevaccination to postvaccination blood samples. Response to treatment was assessed by Response Evaluation Criteria in Solid Tumors. RESULTS: CD8(+) immunity to the native G280 was observed in 8 (67%) patients as measured by ELISPOT and in 12 (100%) patients as measured by tetramer assay. Of the 9 patients tested, 9 (100%) had measurable high-avidity CTL activity as defined by lysis of allogeneic melanoma lines, which coexpress HLA-A*0201 and gp100. The median follow-up of the entire cohort is 43.8 months. Two (17%) partial responses were observed and 3 (25%) patients had stable disease. The median survival of the treated population was 37.6 months. At this time, three patients are alive, including one patient who continues to respond without additional treatment. CONCLUSION: The high rate of immunization as measured by three independent assays and the occurrence of clinical regression support continued investigation of G280-9V peptide as a candidate epitope in melanoma vaccine formulations.

Adult↗

PubMed2005

Repeated cocaine administration induces gene expression changes through the dopamine D1 receptors.

Drug addiction involves compulsive drug-seeking and drug-taking despite known adverse consequences. The enduring nature of drug addiction suggests that repeated exposure to abused drugs leads to stable alterations that likely involve changes in gene expression in the brain. The dopamine D1 receptor has been shown to mediate the long-term behavioral effects of cocaine. To examine how the persistent behavioral effects of cocaine correlate with underlying changes in gene expression, we have used D1 receptor mutant and wild-type mice to identify chronic cocaine-induced gene expression changes mediated via the D1 receptors. We focused on the caudoputamen and nucleus accumbens, two key brain regions that mediate the long-term effects of cocaine. Our analyses demonstrate that repeated cocaine administration induces changes in the expression of 109 genes, including those encoding the stromal cell-derived factor I, insulin-like growth factor binding protein 6, sigma 1 receptor, regulators of G-protein signaling protein 4, Wnt1 responsive Cdc42 homolog, Ca2+/calmodulin-dependent protein kinase II alpha subunit, and cyclin D2, via the D1 receptors. Moreover, the seven genes contain AP-1 binding sites in their promoter regions. These results suggest that genes encoding certain extracellular factors, membrane receptors and modulators, and intracellular signaling molecules, among others, are regulated by cocaine via the D1 receptor, and these AP-1 transcription complex-regulated genes might contribute to persistent cocaine-induced behavioral changes.

Animals↗

PubMed2005

Therapeutic effect of Fe2O3 nanoparticles combined with magnetic fluid hyperthermia on cultured liver cancer cells and xenograft liver cancers.

The therapeutic effect of Fe2O3 nanoparticles combined with magnetic fluid hyperthermia (MFH) on human hepatocarcinoma SMMC-7721 cells in vitro and xenograft liver cancer in nude mice is studied. We examined growth and apoptosis of SMMC-7721 cells treated with MFH containing Fe2O3 nanoparticles at various concentrations (2, 4, 6, and 8 g/liter) for 30-60 min by using MTT, flow cytometry (FCM), and transmission electron microscopy (TEM). We also observed weight and volume inhibitory rates of the tumors of SMMC-7721-bearing nude mice by using animal experiments. The results showed that Fe2O3 nanoparticles combined with MFH could significantly inhibit the proliferation and increase the ratio of apoptosis of SMMC-7721 cells, and the effect was dose-dependent. The inhibitory rate was 26.5%, 33.53%, 54.4%, and 81.2%, respectively, and the apoptosis rate was 30.26%, 38.65%, 50.28%, and 69.33%, respectively. Animal experiments showed that tumors became small. The weight inhibitory ratio was 42.10%, 66.34%, 78.5%, and 91.46%, and the volume inhibitory ratio was 58.77%, 80.44%, 93.40%, and 98.30%, respectively. Compared with the control and experimental groups, each group had statistically significant difference (p < 0.05). So, Fe2O3 nanoparticles combined with MFH could inhibit the proliferation and induce apoptosis of SMMC-7721 cells and also has a significant inhibitory effect on the weight and volume of xenograft liver cancer. However, the mechanism remains to be further investigated.

Animals↗

PubMed2004

C-fos regulates neuropeptide Y expression in mouse dentate gyrus.

Excitotoxicity by which excitatory amino acid induces neuronal cell death may underlie mechanisms of neurodegenerative diseases. We previously found that c-fos is critically involved in neuronal excitability and survival. Mice that carry hippocampal mutations of c-fos exhibited hyper-excitability, hyper-excitotoxicity and higher mortality in kainic acid (KA)-induced seizures compared to wild-type mice. To further understand the neuroprotective signal transduction pathways regulated by c-fos in the hippocampal formation, we identified 172 genes that are either regulated by KA or are differentially expressed in wild-type and hippocampal-specific c-fos mutant mice using cDNA microarrays. One gene encodes the neuropeptide Y (NPY). We confirmed that c-fos regulates the expression of NPY by using immunohistochemistry. We found that c-fos is critical in up-regulation of NPY expression in the granule cell layer of dentate gyrus in response to KA administration. As NPY is an important endogenous anti-epileptic agent, our result is consistent with a hypothesis that the neuroprotective function of c-fos is mediated in part by regulation of NPY expression.

Animals↗

PubMed2004

Cocaine-induced intracellular signaling and gene expression are oppositely regulated by the dopamine D1 and D3 receptors.

Repeated exposure to cocaine can induce neuroadaptations in the brain. One mechanism by which persistent changes occur involves alterations in gene expression mediated by the dopamine receptors. Both the dopamine D1 and D3 receptors have been shown to mediate gene expression changes. Moreover, the D1 and D3 receptors are also coexpressed in the same neurons, particularly in the nucleus accumbens and also caudoputamen (CPu). Little is known however, whether these two receptors coordinately regulate gene expression after cocaine administration and the underlying mechanisms. We have used various gene mutant mice to address this issue. We show that extracellular signal-regulated kinase (ERK) activation and c-fos induction in the CPu in response to acute cocaine administration is mediated by the D1 receptor and inhibited by the D3 receptor. Moreover, ERK activation mediates acute cocaine-induced expression of Fos family genes, including c-fos, fosB and fra2. Interestingly, dynorphin, neogenin, and synaptotagmin VII, genes that possess cAMP-response element binding protein and AP-1 transcription complex-binding consensus sequences in their promoters, are also oppositely regulated by the D1 and D3 receptors after repeated exposure to cocaine. Furthermore, such regulation depends on proper ERK activation and c-fos function. These results suggest that the D1 and D3 receptors elicit opposite regulation of target gene expression by regulating ERK activation and c-fos induction after acute and chronic cocaine treatment.

Animals↗

PubMed2004

Down-regulation of SHP1 and up-regulation of negative regulators of JAK/STAT signaling in HTLV-1 transformed cell lines and freshly transformed human peripheral blood CD4+ T-cells.

Adult T-cell leukemia (ATL) is an aggressive malignancy that is associated with human T-cell lymphotropic virus I (HTLV-I) infection. HTLV-I transformed T-cell lines and fresh ATL cells are characterized by constitutive activation of the interleukin-2 receptor (IL-2R) signaling pathway however, the mechanism(s) responsible for constitutive IL-2R activation are unknown. To further examine the cause of this signaling pathway deregulation, we measured mRNA and protein expression levels by real-time PCR and Western blots, respectively, of four negative regulators of the IL-2R signaling pathway including src homology 2 (SH2)-containing phosphatase (SHP1), cytokine-inducible (CIS) SH2-containing protein, suppressor of cytokine signaling-1 (SOCS1) and protein inhibitor of activated signal transducer and activator of transcription 3 (STAT3) (PIAS3) in six HTLV-1 negative and seven HTLV-1 positive T-cell leukemia lines. The activation status of the JAK/STAT pathway was also examined. SHP1 mRNA and protein expression levels were selectively down regulated in all HTLV-1-infected transformed cell lines, while CIS, SOCS1, and PIAS3 protein expression were markedly but variably upregulated and the cells showed evidence of constitutive STAT3 activation. In acutely HTLV-1 infected primary CD4+ T-cells there was a gradual loss of SHP1 expression over 10 weeks in culture which correlated with progression from immortalization to transformation and loss of IL-2 dependence for growth. Two transformed cell lines that were established following HTLV-1 infection showed loss of SHP1 expression and overexpression of CIS, SOCS1, PIAS3. However, this overexpression was not adequate to block constitutive activation of the JAK/STAT pathway. Thus, multiple levels of IL-2 receptor signal deregulation are found in HTLV-1 transformed cells, which may be a result of early loss of SHP1 expression.

Adult↗

PubMed2003

Optimization of ex vivo activation and expansion of macaque primary CD4-enriched peripheral blood mononuclear cells for use in anti-HIV immunotherapy and gene therapy strategies.

The rhesus macaque model is a useful experimental system to evaluate effects of T-cell autotransfusion and gene therapies for HIV-1 infection and AIDS prior to a clinical trial. To obtain sufficient numbers of primary macaque CD4 T lymphocytes for this purpose, we examined the culture conditions that were needed to optimize ex vivo activation and expansion of macaque primary CD4-enriched peripheral blood mononuclear cells (PBMCs). In this report, we compared the effects of various stimulants on cell expansion, surface expression of CCR5 and CXCR4, and levels of transduction with a Moloney leukemia virus (MoLV) vector encoding the phenotypic selection marker truncated human nerve growth factor receptor (deltaNGFR) alone or with the human anti-HIV-1 tat intrabody sFvhutat2. The use of feeder cells strikingly increased the proliferation rate of macaque CD4-enriched PBMCs in vitro. In the presence of an irradiated rhesus macaque B-lymphoblastoid cell line (BLCL), the highest cell expansion over 21 days was achieved with cells activated by Con A (9648-fold), in turn, from high to low, phytohemagglutinin (PHA) (4855-fold), and anti-CD3/CD28-coated beads (2367-fold). Further studies showed that BLCL feeder cells were more effective than human PBMCs (hPBMCs) in promoting proliferation of macaque CD4-enriched PBMCs activated with Con A and anti-CD3/CD28, respectively. The combined use of both BLCL and hPBMC feeder cells did not further increase cell expansion when compared with the use of BLCL cells alone. In addition, the addition of BLCL-conditioned medium (CM) and hPBMC-CM induced cell growth at a rate higher than did the culture medium alone but not as high as with feeder cells. Con A-activated macaque CD4-enriched PBMCs retained 88% of CXCR4 and 39% of CCR5 expression over 17 days compared with PHA-activated cells (50% for CXCR4, 16% for CCR5) and anti-CD3/CD28-activated cells (34% for CXCR4, 37% for CCR5). Finally, PHA, Con A, and CD3/CD28-coated beads supported comparable levels of MoLV transduction. The results should improve the utility of the rhesus macaque model for the testing of T-cell autotransfusion and gene therapies for HIV-1 infection/AIDS.

Animals↗

PubMed2003

[Structural characteristics of Abies fabri forests at the upper reach of Yangtze River].

The structural characteristics of Abies fabri forest under different succession stages in Gongga Mountains at the upper reach of Yangtze River were studied. The results showed that in the mature Abies fabri forest, there existed abundant seeds and a few saplings of Abies fabri younger than 20 years, but only Abies fabri was the dominant regeneration species. In the poplar-fir mixed forest, the height growth of poplar and birch was very fast during first 30 years, and poplar and birch dominated rapidly over the canopy. Abies fabri had a lower growth rate and a strong shade-tolerance in its first growth stage, and could replace other tree species gradually. The cycle of mud-rock flow occurrence was above 100 years in the Gongga montane areas from elevation of 2800 to 3200 m. After mud-rock flow, poplar and birch often occurred and dominated, and there were only a small number of Abies fabri saplings in slash. Under natural condition, to recover Abies fabri forest would demand a long time, but this process could be controlled and improved by human activities.

Abies↗

PubMed2002

Inhibition of Tat-mediated transactivation and HIV-1 replication by human anti-hCyclinT1 intrabodies.

Human immunodeficiency virus, type 1 (HIV-1) replication requires the interaction of Tat protein with the human cyclinT1 (hCyclinT1) subunit of the positive transcription elongation factor (P-TEFb) complex, which then cooperatively binds to transactivation response element (TAR) RNA to transactivate HIV transcription. In this report, a non-immune human single-chain antibody (sFv) phage display library was used to isolate anti-hCyclinT1 sFvs that could disrupt hCyclinT1-Tat interactions. The N-terminal 272 residues of hCyclinT1, including the entire cyclin domains and the Tat.TAR recognition motif (TRM), that fully support Tat transactivation was used for panning, and of the five unique anti-hCyclinT1 sFvs that were obtained, three bound to the cyclin box domains and two bound to TRM. All sFvs could be expressed as intrabodies at high levels in transiently transfected 293T and in stable Jurkat and SupT1 transfectants and could specifically co-immunoprecipitate co-expressed hCyclinT1 in 293T cells with varying efficacy without disrupting hCyclinT1-Cdk9 interactions. In addition, two sFv clones (3R6-1 and 2R6-21) that mapped to the cyclin box domains markedly inhibited Tat-mediated transactivation in several transiently transfected cell lines without inhibiting basal transcription or inducing apoptosis. When HIV-1 challenge studies were performed on stable 3R6-1-expressing Jurkat T cells, near complete inhibition of viral replication was obtained at a low challenge dose, and 74-88% inhibition to HIV-1 replication was achieved at a high infection dose in SupT1 cells. These results provide proof-in-principle that anti-hCyclinT1 intrabodies can be designed to block HIV-1 replication without causing cellular toxicity, and as a result, they may be useful agents for "intracellular immunization"-based gene therapy strategies for HIV-1 infection/AIDS.

Amino Acid Sequence↗

PubMed2002

c-fos regulates neuronal excitability and survival.

Excitotoxicity is a process in which glutamate or other excitatory amino acids induce neuronal cell death. Accumulating evidence suggests that excitotoxicity may contribute to human neuronal cell loss caused by acute insults and chronic degeneration in the central nervous system. The immediate early gene (IEG) c-fos encodes a transcription factor. The c-Fos proteins form heterodimers with Jun family proteins, and the resulting AP-1 complexes regulate transcription by binding to the AP-1 sequence found in many cellular genes. Emerging evidence suggests that c-fos is essential in regulating neuronal cell survival versus death. Although c-fos is induced by neuronal activity, including kainic acid-induced seizures, whether and how c-fos is involved in excitotoxicity is still unknown. To address this issue, we generated a mouse in which c-fos expression is largely eliminated in the hippocampus. We found that these mutant mice have more severe kainic acid-induced seizures, increased neuronal excitability and neuronal cell death, compared with control mice. Moreover, c-Fos regulates the expression of the kainic acid receptor GluR6 and brain-derived neurotrophic factor (BDNF), both in vivo and in vitro. Our results suggest that c-fos is a genetic regulator for cellular mechanisms mediating neuronal excitability and survival.

Animals↗

PubMed2002

The dopamine D1 receptor is a critical mediator for cocaine-induced gene expression.

The dopamine D1 receptor plays a major role in mediating behavioral responses to cocaine administration. The time course for the acquisition and the relative stability for the expression of behavioral responses suggest the involvement of enduring neuroadaptations in response to repeated cocaine exposure. Changes in gene expression through the D1 receptors may accompany and mediate the development of such neuroadaptations to repeated cocaine stimulation. To test this possibility, we systematically compared the expression of the fos and Jun family immediate early genes in the nucleus accumbens and caudoputamen in D1 receptor mutant and wild-type control mice after acute and repeated cocaine exposure. Moreover, we compared the expression of three molecules that have been implicated in mediating the actions of cocaine, Galphaolf, beta-catenin and brain-derived neurotrophic factor, in the two groups of mice before and after cocaine administration. We found that there is a lack of induction of c-Fos, FosB, Fra-2 and JunB by acute cocaine exposure, and of DeltaFosB by repeated cocaine administration in both the NAc and CPu of D1 receptor mutant mice compared with wild-type control mice. Moreover, the D1 receptor is differentially required for mediating Galphaolf, beta-catenin and BDNF expression in the NAc and CPu upon cocaine exposure. These results suggest that the D1 receptor is a critical mediator for cocaine-induced expression of these genes.

Animals↗