Biomedical subjects

Y Jin

Publications and source records attributed to Y Jin.

At least 163 records · Page 9Linked to original sources

PubMed2000

Characterization of a thrombin-like enzyme from the venom of Trimeresurus jerdonii.

From the venom of Trimeresurus jerdonii, a distinct thrombin-like enzyme, called jerdonobin, was purified by DEAE A-25 ion-exchange chromatography, Sephadex G-75 gel filtration, and fast protein liquid chromatography (FPLC). SDS-PAGE analysis of this enzyme shows that it consists of a single polypeptide chain with a molecular weight of 38,000. The NH(2)-terminal amino acid sequence of jerdonobin has great homology with venom thrombin-like enzymes documented. Jerdonobin is able to hydrolyze several chromogenic substrates. The enzyme directly clots fibrinogen with an activity of 217 NIH units/mg. The fibrinopeptides released, identified by HPLC, consisted of fibrinopeptide A and a small amount of fibrinopepide B. The activities of the enzyme were inhibited by phenylmethylsulfonyl fluoride (PMSF) and p-nitrophenyl-p-guanidinobenzoate (NPGB). However, metal chelator (EDTA) had no effect on it, indicating it is venom serine protease.

Amino Acid Sequence↗

PubMed2000

Bone marrow cells inhibit the generation of autologous EBV-specific CTL.

Recently, we reported that human bone marrow cells (BMC) inhibited the proliferative (recall) response of lymphocytes to Epstein-Barr virus (EBV) and cytomegalovirus (CMV) protein antigens [12]. To clarify further the effect of BMC on the immune response to viral antigens, we obtained PBL from EBV IgG antibody positive kidney transplant recipients (R) and their living-related donors (LRD) 1 year after renal transplantation and generated EBV-specific CTL in vitro in the presence or absence of autologous BMC. The addition of freshly aspirated autologous iliac crest BMC from either R or LRD caused a significant inhibitory effect on the generation of EBV-specific CTL from CTL precursors, in contrast to the addition of autologous PBL used as controls (62.29 +/- 10.85% inhibition using BMC from the kidney transplant recipients; 74.47 +/- 15.21% inhibition using BMC from the living-related donors). This inhibitory effect was only exerted during the CTL generation phase; but not in the effector CTL killing phase. The expression of CD94, a component of the killer inhibitory receptor (KIR) on CD3(+) cells was elevated in the cultures with BMC, in contrast to the cultures without BMC. The BMC inhibitory effect was partially abrogated by pre-incubation of the CTL effectors with anti-CD94 monoclonal antibody, in contrast with its isotype control. In addition, supernatants obtained from the CTL generating cultures with BMC contained high levels of prostaglandin E(2) (PGE(2)), and EBV-specific CTL activity was inhibited by the addition of exogenous PGE(2) in the absence of BMC. The induction of CD40L cell surface expression by anti-CD3 was also decreased on the effector T cell population when BMC were added. There was a concomitant reduction in protein kinase C (PKC) activity. These studies demonstrate that BMC exert an inhibitory effect on T cell-mediated immunity to viral antigens in humans by regulating autologous effector T cell generation and early T cell activation signaling pathways.

Antigens, CD↗

PubMed2000

Bone marrow cells promote TH2 polarization and inhibit virus-specific CTL generation.

This laboratory recently reported that human bone marrow cells (BMC) inhibit the generation of virus-specific CTL in culture. The culture supernatants contained increased levels of prostaglandin E(2) (PGE(2)) (shown to favor TH2 cell development) and also inhibited EBV-CTL effector cell development. In this study, we obtained PBL from Epstein-Barr virus (EBV) IgG antibody positive kidney transplant recipients (R) and their living-related donors (LRD) one year after renal transplantation. EBV-specific CTL were then generated in vitro by stimulating PBL with autologous EBV-transformed B cells (EBV-B) in the presence or absence of autologous BMC. The addition of BMC to the EBV-CTL generation cultures increased the intracellular expression in CD3+ cells of IL-4,-5,-6,-10, and -13. These CD3+ cells also expressed increased levels of the TH2 associated receptor CCR3. Inhibition was even observed by preparing EBV-CTL generating cultures in trans-wells that separated the autologous BMC from the PBL + EBV-B. It was then observed that CD3+ cells obtained after 7 days of culture in the presence of autologous BMC could be used as inhibitors of EBV-CTL generation. Protein Kinase A (PKA), a cAMP kinase that is involved in the upregulation of TH2 cytokine activity, was increased in EBV-CTL cultures by the presence of BMC. Additionally, IL-4-mediated signal transduction and activation of transcription (STAT-6) phosphorylation was slightly increased. These results show that the BMC inhibition is mediated by soluble factors (cytokines) and that cell-cell contact in this autologous system is not required, so that BMC (at least partially, via cytokine production) promote TH2 polarization in culture. Moreover, TH2 cells induced by culturing with autologous BMC directly inhibit EBV-CTL generation, and TH2 associated PKA, CCR3, and STAT-6 phosphorylation are enhanced by BMC.

Bone Marrow Cells↗

PubMed2000

Regulation of presynaptic terminal organization by C. elegans RPM-1, a putative guanine nucleotide exchanger with a RING-H2 finger domain.

Presynaptic terminals contain highly organized subcellular structures to facilitate neurotransmitter release. In C. elegans, the typical presynaptic terminal has an electron-dense active zone surrounded by synaptic vesicles. Loss-of-function mutations in the rpm-1 gene result in abnormally structured presynaptic terminals in GABAergic neuromuscular junctions (NMJs), most often manifested as a single presynaptic terminal containing multiple active zones. The RPM-1 protein has an RCC1-like guanine nucleotide exchange factor (GEF) domain and a RING-H2 finger. RPM-1 is most similar to the Drosophila presynaptic protein Highwire (HIW) and the mammalian Myc binding protein Pam. RPM-1 is localized to the presynaptic region independent of synaptic vesicles and functions cell autonomously. The temperature-sensitive period of rpm-1 coincides with the time of synaptogenesis. rpm-1 may regulate the spatial arrangement, or restrict the formation, of presynaptic structures.

Adaptor Proteins, Signal Transducing↗

PubMed2000

Novel glycosides from noni (Morinda citrifolia).

Three new glycosides were isolated from the fruits of noni (Morinda citrifolia). Their structures were determined to be 6-O-(beta-D-glucopyranosyl)-1-O-octanoyl-beta-D-glucopyranose (1), 6-O-(beta-D-glucopyranosyl)-1-O-hexanoyl-beta-D-glucopyranose (2), and 3-methylbut-3-enyl 6-O-beta-D-glucopyranosyl-beta-D-glucopyranoside (3) using MS and NMR methods.

Chromatography, Gel↗

PubMed2000

Expression of c-jun in the lateral vestibular nucleus following spinal cord injury and peripheral nerve graft transplantation in adult rats.

The time course of c-jun expression and the effect of a peripheral nerve (PN) graft on axonal regeneration and c-jun expression in the lateral vestibular nucleus (LVN) were investigated in this study. c-Jun was found in LVN neurons 1 day after hemisection of the spinal cord at C3, with weak immunoreactivity. Strong c-Jun positive immunoreactivity was found 3 days post-injury. The expression of c-jun reached its maximum level (45% +/- 2.5, mean +/- SD) 1 week post-injury and gradually decreased to about a third of its peak value 6 weeks after the inflicted lesion. The PN graft implanted at the lesion site significantly enhanced the number of neurons expressing c-jun 4 weeks after PN transplantation (from 20% of LVN neurons in axotomy alone to 30% in PN graft transplantation, P < 0. 05). The PN graft induced injured neurons to regrow into the PN graft. About 91 FG-labeled neurons were found in the LVN and approximately 87% of these neurons showed c-Jun positive immunoreactivity. The high percentage of regenerating neurons expressing c-jun suggested that c-Jun might be involved in the regenerative process. The result of double staining for c-Jun and NOS showed that approximately 93% NOS positive neurons co-expressed c-Jun. Comparing the time course of the appearance of c-Jun with that of NOS, the expression of c-jun preceded that of NOS. Although a high percentage of NOS reactive neurons expressed c-jun, the expression of NOS in damaged LVN neurons needs to be further investigated.

Age Factors↗

PubMed2000

Bronchial granular cell tumor with osteopontin and osteonectin expression: a case report.

The case of a 52-year-old Japanese man with bronchial granular cell tumors with osteopontin and osteonectin expression is reported here because there have been few investigations of their expression in benign tumors. He was admitted because of sudden hematemesis. A bronchoscopic examination revealed a lobulated polypoid tumor located in the left and right bronchi. Histologically, most tumor cells had abundant granular eosinophilic cytoplasm and were immunoreactive for S-100, neuron-specific enolase (NSE), CD68 and vimentin. Moreover, osteopontin-positive tumor cells were randomly distributed in the tumor tissue, but few stromal cells were positive. In contrast, osteonectin was mainly expressed in the peripheral tumor cells and was also distributed in the stromal cells. Blood vessels at the tumor border in which osteonectin-positive tumor cells were distributed, proliferated moderately. These results suggest that osteopontin and osteonectin may play a role in the progression of granular cell tumors and in the interaction between the tumor and host or angiogenesis around the tumor, respectively.

Biomarkers, Tumor↗

PubMed2000

Effect of application volume of ethanol-isopropyl myristate mixed solvent system on permeation of zidovudine and probenecid through rat skin.

Permeation of zidovudine (AZT) and probenecid from an ethanol-isopropyl myristate (IPM) mixed system through rat skin was studied in a finite system. Several volume sizes of the ethanol-IPM mixed systems containing AZT and probenecid, both as suspensions, were applied on the skin of the hairless rat using a vertical glass cell, and the fractions of the drugs permeated in 8 hr Q%,8 hr were determined. For the systems containing 40% ethanol, the Q%,8 hr value decreased with the reduction of volume of the system applied, and the decreasing profile was similar to that calculated on the assumption that the permeability of the drug does not change with the volume of the sample applied. On the other hand, in the systems containing 10% or 20% ethanol, the Q%,8 hr value showed a maximum when a specific volume of the sample was applied. Therefore, the effect of sample volume on the Q%,8 hr value was different between the 40% ethanol-IPM system and the 10% or 20% ethanol-IPM system. Following pretreatment of the skin with 0.105 ml/cm2 of drug-free 40% ethanol-IPM for 2 hr, several volume sizes of 10% ethanol-IPM systems containing the drugs were applied on the skin to explain why the different profiles were observed in the system containing 10% or 20% ethanol. The results for pretreated skin suggest that the amount of ethanol in the systems with low ethanol concentration and small application volume is too small to exert an effect that enhances permeation of the drugs. In those systems, the integrated effect of ethanol on the skin would be important for the enhancing effect. Total volume, as well as concentration, of an enhancer should be set precisely in designing an efficient transdermal delivery system.

Administration, Cutaneous↗

PubMed2000

Effect of inhaled nitric oxide on cardiovascular response to catecholamine in heart failure.

We examined the dose responses to continuous infusion of isoproterenol (ISO) and norepinephrine (NE) in normal (control) and procainamide-induced heart failure dogs with or without inhalation of 70 ppm nitric oxide (NO). Inhaled NO affected neither left ventricular (LV) function nor hemodynamics at baseline in both control and heart failure dogs. There were no significant differences in the responses to ISO and NE with or without inhaled NO in the control. The responses of LV dP/dt to ISO and NE were significantly enhanced in heart failure; however, they were not affected by inhaled NO. In contrast, LV pressure and dimension at end diastole were significantly increased, and pulmonary vascular resistance (PVR) was significantly decreased by inhaled NO during infusion of both ISO and NE in heart failure. In conclusion, the positive inotropic response to cathecholamine is not affected by inhaled NO even in heart failure. Inhaled NO decreases PVR, but potentially increases LV preload in the presence of additional stress of cathecholamine in heart failure.

Administration, Inhalation↗

PubMed2000

Alterations in expression of myosin and myosin light chain kinases in response to vascular injury.

Histochemical analysis of balloon-injured rat carotid arteries revealed a coordinated expression of nonmuscle myosin heavy chain-A and -B (NM-A and NM-B) in response to injury. Expression of these nonmuscle myosin forms shifts from the media to the adventitia and intima. In contrast, expression of smooth muscle myosin heavy chain-1 (SM-1) within the media is not altered, whereas smooth muscle myosin heavy chain-2 (SM-2) expression declines. Western blotting shows a statistically significant increase in expression of NM-A that occurs within 6 h in response to carotid injury, suggesting this myosin form may be an appropriate experimental marker for proliferating, migrating cells in injured vessels. No overall change in the relative expression level of NM-B was detected, suggesting that compensatory declines in media expression are balanced by increases in the intima and adventitia. Expression of SM-1 did not change in response to injury, whereas the expression of SM-2 significantly declined between 24 h and 7 days. Expression of myosin light chain kinase is also negatively regulated, and the decline in its expression parallels downregulation of SM-2.

Animals↗

PubMed2000

Angiogenesis and morphogenesis of murine fetal distal lung in an allograft model.

Neovascularization is crucial to lung morphogenesis; however, factors determining vessel growth and formation are poorly understood. The goal of our study was to develop an allograft model that would include maturation of the distal lung, thereby ultimately allowing us to study alveolar development, including microvascular formation. We transplanted 14-day gestational age embryonic mouse lung primordia subcutaneously into the back of nude mice for 3.5-14 days. Lung morphogenesis and neovascularization were evaluated by light microscopy, in situ hybridization, and immunohistochemical techniques. Embryonic 14-day gestational age control lungs had immature structural features consistent with pseudoglandular stage of lung development. In contrast, 14 days after subcutaneous transplantation of a 14-day gestational age lung, the allograft underwent significant structural morphogenesis and neovascularization. This was demonstrated by continued neovascularization and cellular differentiation, resulting in mature alveoli similar to those noted in the 2-day postnatal neonatal lung. Confirmation of maturation of the allograft was provided by progressive type II epithelial cell differentiation as evidenced by enhanced local expression of mRNA for surfactant protein C and a threefold (P < 0.008) increase in vessel formation as determined by immunocytochemical detection of platelet endothelial cell adhesion molecule-1 expression. Using the tyrosine kinase Flk-1 receptor (flk-1) LacZ transgene embryos, we determined that the neovascularization within the allograft was from the committed embryonic lung endothelium. Therefore, we have developed a defined murine allograft model that can be used to study distal lung development, including neovascularization. The model may be useful when used in conjunction with an altered genetic background (knockout or knock in) of the allograft and has the further decided advantage of bypassing placental barriers for introduction of pharmacological agents or DNA directly into the lung itself.

Animals↗

PubMed2000

Fibroblasts genetically modified to produce BDNF support regrowth of chronically injured serotonergic axons.

Cells genetically modified to release a variety of growth and/or neurotrophic factors have been used for transplantation into the injured spinal cord as a means to deliver therapeutic products. Axon growth into and through such transplants has been demonstrated after intervention after an acute injury. The present study examined their potential to support regeneration in a chronic injury condition. Five weeks after a cervical hemisection in adult rats, the lesion site was debrided of scar tissue and expanded in both rostral and caudal directions. Animals received a transplant of cultured normal fibroblasts (control) or fibroblasts genetically modified to produce brain-derived neurotrophic factor (BDNF). Six weeks later, animals were killed to determine the extent of growth of serotonergic axons into the transplant. Axons immunoreactive for serotonin (5-HT-ir) were found to cross the rostral interface of host spinal cord readily with either type of fibroblast cell transplant, but the number and density of 5-HT-ir axons extending into the BDNF-producing transplants was markedly greater than those in the control fibroblasts. Axons coursed in all directions among normal fibroblast transplants, whereas growth was more oriented along a longitudinal plane when BDNF was being released by the transplanted cells. The length of growth and the percentage of the transplant length occupied by 5-HT-ir axons were significantly greater in BDNF-producing transplants than in the normal fibroblasts. Many serotonergic axons approached the caudal end of the BDNF-producing cell transplants, although most failed to penetrate the host spinal cord distal to the lesion. These results indicate that whereas fibroblast cell transplants alone can support regrowth of axons from chronically injured supraspinal neurons, modification of these cells to produce BDNF results in a significant increase in the extent of growth into the transplant.

Animals↗

PubMed2000

The C. elegans NeuroD homolog cnd-1 functions in multiple aspects of motor neuron fate specification.

The basic helix-loop-helix transcription factor NeuroD (Neurod1) has been implicated in neuronal fate determination, differentiation and survival. Here we report the expression and functional analysis of cnd-1, a C. elegans NeuroD homolog. cnd-1 expression was first detected in neuroblasts of the AB lineage in 14 cell embryos and maintained in many neuronal descendants of the AB lineage during embryogenesis, diminishing in most terminally differentiated neurons prior to hatching. Specifically, cnd-1 reporter genes were expressed in the precursors of the embryonic ventral cord motor neurons and their progeny. A loss-of-function mutant, cnd-1(ju29), exhibited multiple defects in the ventral cord motor neurons. First, the number of motor neurons was reduced, possibly caused by the premature withdrawal of the precursors from mitotic cycles. Second, the strict correlation between the fate of a motor neuron with respect to its lineage and position in the ventral cord was disrupted, as manifested by the variable expression pattern of motor neuron fate specific markers. Third, motor neurons also exhibited defects in terminal differentiation characteristics including axonal morphology and synaptic connectivity. Finally, the expression patterns of three neuronal type-specific transcription factors, unc-3, unc-4 and unc-30, were altered. Our data suggest that cnd-1 may specify the identity of ventral cord motor neurons both by maintaining the mitotic competence of their precursors and by modulating the expression of neuronal type-specific determination factors. cnd-1 appears to have combined the functions of several vertebrate neurogenic bHLH proteins and may represent an ancestral form of this protein family.

Amino Acid Sequence↗

PubMed2000

Preparation and characterization of hyaluronate-hydroxyethyl acrylate blend hydrogel for controlled release device.

Hyaluronate-hydroxyethyl acrylate blend hydrogels were investigated as matrices for controlled release devices. Glycidyl methacrylate (GMA) derivatized HA (GMA-HA) was synthesized by coupling of GMA to HA in the presence of a suitable catalyst. These hydrogels were prepared by a free radical copolymerization of GMA-HA and hydroxyethyl acrylate. The water content of these hydrogels at equilibrium swelling in water (Ww) was 0.978+/-0.0073 (n=18); however, these hydrogel was mechanically tough and could be used as disk shape. The hydrogels swelling were found to depend on ionic strength and pH. The dried hydrogels quickly regained their original condition in water, and they swelled to more than 90% of its initial water contents after 30 min. This swelling-deswelling behavior was reproducible. The release of chlorpromazine HCl as a model cationic drug from the gels was suppressed significantly in water. The release increased with increasing the ionic strength and decreasing pH of bulk solutions.

Delayed-Action Preparations↗

PubMed2000

Dietary variables and glucose tolerance in pregnancy.

OBJECTIVE: To investigate relationships between dietary macronutrient intakes and glucose tolerance in pregnancy RESEARCH DESIGN AND METHODS: Nulliparous pregnant Chinese women diagnosed with gestational diabetes mellitus (GDM) (n = 56) were compared to age-, gestational age-, height-, and parity-matched groups with normal glucose tolerance (n = 77) and glucose intolerance (IGT) (n = 38) based on the results of an oral glucose tolerance test (National Diabetes Data Group criteria), performed between 24 and 28 weeks of pregnancy. A 24-h recall dietary assessment was also obtained at the time of screening. RESULTS: Subjects with IGT and GDM were significantly heavier (66.1 +/- 1.4 and 68.6 +/- 1.2 kg, respectively, mean +/- SEM) (P < 0.0001) than the normal group (61.2 +/- 1.8 kg) and had a higher BMI. Overall energy intake was similar between groups, as were the intakes of each macronutrient (%kcal). However, there was a highly significant reduction in polyunsaturated fat intake in the IGT and GDM groups whether expressed as %kcal, % of total fat, or fat kcal. This effect was independent of body weight or BMI whether assessed by ordinal logistic regression or by analysis of a weight- and BMI-matched subgroup of the subjects (P = 0.002 for %kcal; n = 47 normal, 26 IGT, and 43 GDM subjects). In logistic regression analysis of the complete data set, increased body weight (P < 0.0001) and decreased polyunsaturated fat intake (P = 0.0014) were both independent predictors of glucose intolerance (IGT and GDM), as were increased body weight and a low dietary polyunsaturated to saturated fat ratio. CONCLUSIONS: Increased polyunsaturated fat intake is associated with a reduced incidence of glucose intolerance during pregnancy. This finding may have major implications for dietary management of women with or at risk of developing GDM.

Adult↗

PubMed2000

Comparative polymerase chain reaction analysis of c-myc amplification on archival breast fine-needle aspiration materials.

The oncogene c-myc is a key regulator of cell cycle progression (from G1 to S phase). The amplification of c-myc can either induce cell proliferation or apoptosis. As a part of our ongoing effort to develop methods for multiple tumor marker analysis, this study was carried out to determine whether biomarkers such as c-myc amplification could be analyzed on genetic materials collected from archival fine-needle aspiration (FNA) smears. A novel comparative PCR analysis was used to analyze c-myc amplification semiquantitatively. Genomic DNA was prepared using cells obtained from archival FNA materials that had undergone quantitative fluorescence image analysis (QFIA) for other biomarkers. Of the 72 cases selected from 1995 for this study, 53 had an adequate amount of DNA for analysis. A novel comparative PCR analysis was used to analyze c-myc amplification quantitatively. For each batch of experiments, DNA from the high c-myc expressing cells, HL-60, and DNA from the low expressing cells, K562, were served as positive and negative controls, respectively. c-myc amplification was observed in 16 (94.1%) of 17 malignant lesions, 5 (41.7%) of 12 proliferative breast diseases with nuclear atypia, and 4 (16.7%) of 24 other benign lesions (fibroadenoma or fibrocystic disease). The overall difference of c-myc expression among these groups was highly significant by chi2 analysis (P = 0.0002). We conclude that multiple phenotypic markers and genotypic markers may be combined in a risk assessment biomarker profile on small FNA samples that can be obtained on multiple occasions relatively noninvasively from the patient. The results of this study suggest that c-myc amplification may be a biomarker of breast cancer risk. However, additional large, prospective studies are needed to confirm the current observation.

Adult↗

PubMed2000

Nonrandom pattern of cytogenetic abnormalities in squamous cell carcinoma of the larynx.

Cytogenetic analysis of short-term cultures from 105 squamous cell carcinomas of the larynx (LSCC) revealed clonal chromosome aberrations in 56 tumors. Simple karyotypic changes (less than four aberrations per clone) were found in 24 cases, and the remaining 32 tumors had complex karyotypes with multiple numerical as well as unbalanced structural rearrangements. Extensive intratumor heterogeneity, in the form of multiple related subclones or unrelated clones, was observed in a large fraction of the tumors. The structural changes most often affected chromosomes 3, 1, 11, 7, 2, 15, 5, 4, 8, and 12, with rearrangements in the centromeric regions, i.e., the centromeric bands p10 and q10 and the juxtacentromeric bands p11 and q11, accounting for 43% of the total breakpoints. The most common imbalances brought about by numerical and unbalanced structural rearrangements were loss of chromosomal region 3p21-pter, chromosome arms 4p, 6q, 8p, 10p, 13p, 14p, 15p, and 17p, and gain of chromosomal regions 3q21-qter, 7q31-pter, and 8q. Among 17 recurrent aberrations identified, the most common were i(8q), hsr(11)(q13), i(3q), i(5p), and del(3)(p11). No statistically significant association was found between major karyotypic features and histological differentiation or TNM stage. The karyotypic features of the LSCC were also compared with previously published oral SCC, a subgroup of SCC that has been more extensively characterized cytogenetically. No clear-cut karyotypic differences were found between LSCC and oral SCC, with the exception that i(8q) was significantly more frequent among the latter.

Adult↗

PubMed2000

Role for early growth response-1 protein in alpha(1)-adrenergic stimulation of fibroblast growth factor-2 promoter activity in cardiac myocytes.

Fibroblast growth factor-2 (FGF-2), a mitogenic, angiogenic, and cardioprotective agent, is released from the postnatal heart by a mechanism of transient remodelling of the sarcolemma during contraction. Both release of FGF-2 and its synthesis can be increased with adrenergic stimulation. We reported previously that FGF-2 synthesis can be regulated at the transcriptional level by alpha-adrenergic stimulation of cultured neonatal rat cardiac myocytes as well as in the adult mouse heart. Examination of the proximal promoter region of both human and rat FGF-2 gene sequences revealed binding sites for the early growth response-1 (Egr-1) protein. Using gel mobility shift assays, we observed a transient increase in a complex between nuclear extracts from neonatal rat cardiac myocytes treated with inducers of Egr-1, including the alpha-adrenergic agonist phenylephrine, angiotensin II, and phorbol ester, and a consensus Egr-1 DNA element. A similar complex was seen with the FGF-2 promoter region -7/+42 as the DNA probe, but not when the Egr-1 element at nucleotides +3/+31 was disrupted. Participation of Egr-1 protein in the complex was confirmed by competition with Egr-1 DNA elements and antibodies. With deletion analysis and transfection of neonatal rat cardiac myocytes, the alpha-adrenergic response was localized to nucleotides -110/+42 of the FGF-2 gene in the context of a hybrid FGF-2/luciferase reporter gene, -110FGFp.luc. Overexpression of Egr-1 increased -110FGFp.luc gene expression, whereas mutation of its Egr-1 element at nucleotides +3/+31 abolished alpha-adrenergic responsiveness. These data indicate that Egr-1 is involved in the alpha-adrenergic stimulation of the FGF-2 promoter region in neonatal cardiac myocytes.

Angiotensin II↗