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C Yamamoto

Publications and source records attributed to C Yamamoto.

At least 19 recordsLinked to original sources

Cycloprodigiosin hydrochloride, H(+)/CL(-) symporter, induces apoptosis and differentiation in HL-60 cells.

Cycloprodigiosin hydrochloride (cPrG * HCl), a novel H(+)/Cl(-) symporter, induces acidification of the cytosol and leads to apoptosis in rat and human liver cancer cells. In the present study, the effect of cPrG * HCl on a promyelocytic leukemia cell line (HL-60) was examined. cPrG * HCl lowered intracellular pH and induced apoptosis through up-regulation of Fas ligand, activation of stress-activated protein kinase (SAPK/JNK) and caspase. Apoptosis induced by cPrG * HCl was strongly suppressed when a cell-permeable weak base, imidazole, was present, indicating that cytosol acidification introduced by cPrG * HCl triggered caspase activation, leading to apoptosis. Concomitantly, cell differentiation into monocyte was also induced by cPrG * HCl both morphologically and functionally. However, the cPrG * HCl-induced differentiation was not suppressed by addition of imidazole, indicating that the differentiation process is unrelated to cytosol acidification. Further, the differentiation induced by cPrG * HCl was blocked by tyrosine kinase inhibitors (lavendustin A and HMA) but unaffected by the inhibitors of A-kinase (H-89) or C-kinase (H-7). Taken together, these findings suggest that cPrG * HCl, through apoptosis and differentiation induction, may be useful in leukemia treatment.

Antiporters↗

Cell density-dependent regulation of proteoglycan synthesis by transforming growth factor-beta(1) in cultured bovine aortic endothelial cells.

The regulation of vascular endothelial cell behavior during angiogenesis and in disease by transforming growth factor-beta(1) (TGF-beta(1)) is complex, but it clearly involves growth factor-induced changes in extracellular matrix synthesis. Proteoglycans (PGs) synthesized by endothelial cells contribute to the formation of the vascular extracellular matrix and also influence cellular proliferation and migration. Since the effects of TGF-beta(1) on vascular smooth muscle cell growth are dependent on cell density, it is possible that TGF-beta(1) also directs different patterns of PG synthesis in endothelial cells at different cell densities. In the present study, dense and sparse cultures of bovine aortic endothelial cells were metabolically labeled with [(3)H]glucosamine, [(35)S]sulfate, or (35)S-labeled amino acids in the presence of TGF-beta(1). The labeled PGs were characterized by DEAE-Sephacel ion exchange chromatography and Sepharose CL-4B molecular sieve chromatography. The glycosaminoglycan M(r) and composition were analyzed by Sepharose CL-6B chromatography, and the core protein M(r) was analyzed by SDS-polyacrylamide gel electrophoresis, before and after digestion with papain, heparitinase, or chondroitin ABC lyase. These experiments indicate that the effect of TGF-beta(1) on vascular endothelial cell PG synthesis is dependent on cell density. Specifically, TGF-beta(1) induced an accumulation of small chondroitin/dermatan sulfate PGs (CS/DSPGs) with core proteins of approximately 50 kDa in the medium of both dense and sparse cultures, but a cell layer-associated heparan sulfate PG with a core protein size of approximately 400 kDa accumulated only in dense cultures. Moreover, only in the dense cell cultures did TGF-beta(1) cause CS/DSPG hydrodynamic size to increase, which was due to the synthesis of CS/DSPGs with longer glycosaminoglycan chains. The heparan sulfate PG and CS/DSPG core proteins were identified as perlecan and biglycan, respectively, by Western blot analysis. The present data suggest that TGF-beta(1) promotes the synthesis of both perlecan and biglycan when endothelial cell density is high, whereas only biglycan synthesis is stimulated when the cell density is low. Furthermore, glycosaminoglycan chains are elongated only in biglycan synthesized by the cells at a high cell density.

Amino Acids↗

Cycloprodigiosin hydrochloride, a H+/Cl- symporter, induces apoptosis in human breast cancer cell lines.

The effect of cycloprodigiosin hydrochloride (cPrG.HCl), a H+/Cl- symporter, on five human breast cancer cell lines (KPL-1, T-47D, MCF-7, MKL-F, and MDA-MB-231), a human breast epithelial cell line (HBL-100), and a human fibroblast cell line (WI-38-40) was examined. cPrG.HCl inhibited the growth of all five breast cancer cell lines (IC50: 0.46-0.62 microM) and slightly inhibited HBL-100 and WI-38-40 cell growth (IC50: 1.75 microM and 2.26 microM respectively). cPrG.HCl treatment in KPL-1 cells increased the pH of acidic organelles, decreased intracellular pH, and caused apoptosis, which was confirmed by the appearance of a sub-G1 population by flow cytometry and DNA fragmentation. In addition, cPrG.HCl-induced apoptosis was strongly suppressed by imidazole, a cell-permeable base, suggesting that intracellular acidification was essential for the apoptosis. Further, cPrG.HCl treatment up-regulated Bax and Bak expression, down-regulated Bcl-2 expression, and activated caspase-3. Therefore, the intracellular acidification by cPrG.HCl treatment suppressed the growth of human breast cancer cell lines by inducing apoptosis.

Antiporters↗

Immune response of tonsillar lymphocytes to Haemophilus parainfluenzae in patients with IgA nephropathy.

The pathogenesis of IgA nephropathy (IgAN) is unclear. We have previously shown glomerular deposition of Haemophilus parainfluenzae (HPI) antigens and the presence of IgA antibody against HPI antigens in patients with IgAN. We examined the immune response to HPI antigens in tonsillar lymphocytes from patients with IgAN. Lymphocytes isolated from the palatine tonsils of 13 IgAN patients and 16 patients with chronic tonsillitis but without renal disease were used as controls. We examined lymphocyte proliferation and production of IgA antibody against HPI antigens by measuring thymidine uptake and IgA antibody in culture supernatants after lymphocyte incubation with HPI antigens. Patients with IgAN showed a significantly higher stimulation index to HPI antigens (thymidine incorporation in tonsillar lymphocytes with HPI/thymidine incorporation in unstimulated tonsillar lymphocytes) than controls (P < 0.002). Lymphocytes from patients with IgAN also showed a significantly higher level of IgA antibody and IgA1 antibody against HPI antigens in culture supernatants than lymphocytes from controls (P = 0.0002 and P = 0.004, respectively). Our results suggest that HPI antigens stimulate tonsillar T and B lymphocytes in patients with IgAN and that an immune response to HPI antigens may play a role in the pathogenesis of this disease in some cases.

Adolescent↗

Synthesis of immunoglobulins against Haemophilus parainfluenzae by tonsillar lymphocytes from patients with IgA nephropathy.

BACKGROUND: We previously demonstrated glomerular deposition of Haemophilus parainfluenzae (HP) antigens and the presence of IgA antibody against HP antigens in patients with IgA nephropathy (IgAN). In this report we examine the synthesis of immunoglobulins against HP antigens in tonsillar lymphocytes from patients with IgAN. METHODS: We used tonsillar lymphocytes isolated from the palatine tonsils of 15 patients with IgAN and 16 patients with chronic tonsillitis but without renal disease. We examined lymphocyte proliferation and production of IgA, IgG, and IgM antibodies against HP antigens by measuring thymidine uptake and concentrations of these antibodies in culture supernatants after lymphocyte incubation with HP antigens by ELISA. RESULTS: Lymphocytes from patients with IgAN showed a significantly higher stimulation index (SI) on exposure to HP antigens (thymidine incorporation in tonsillar lymphocytes exposed to HP (c.p.m.)/ thymidine incorporation in unstimulated tonsillar lymphocytes (c.p.m.)) than did controls (P=0. 0015). Lymphocytes from patients with IgAN also showed a significantly higher IgA SI (concentrations of IgA against HP antigens in supernatants from HP-stimulated lymphocytes/IgA against HP antigens in supernatants from unstimulated tonsillar lymphocytes) than did controls (P=0.0004). We found positive correlations between concentrations of IgA and IgG antibodies, between IgA and IgM antibodies, and between IgG and IgM antibodies against HP antigens after HP stimulation. CONCLUSIONS: Our results suggest that HP antigens stimulate tonsillar T and B lymphocytes in patients with IgAN and that these patients have polyclonal activation of lymphocytes against HP antigens, with isotype switching of antibody production from IgM to IgA.

Adolescent↗

[Toxicity of cadmium and lead on vascular cells that regulate fibrinolysis].

Cadmium and lead are heavy metals that cause vascular lesions such as atherosclerosis and hypertension. Toxicity of cadmium and lead on the regulation of fibrinolysis by vascular-composing cells was investigated using a cell culture system. It was found that cadmium promotes the synthesis of plasminogen activator inhibitor-1 (PAI-1) whereas lead inhibits the synthesis of tissue plasminogen activator (t-PA) in vascular endothelial cells; consequently, both heavy metals reduced fibrinolytic activity in the liquid phase. The responses of endothelial cells to cadmium and lead were different from those to other heavy metals and the release of the fibrinolytic proteins from vascular smooth muscle cells and fibroblasts was perturbed by cadmium and lead in different manners. In conclusion, the present study showed that cadmium and lead exhibit their toxicity on fibrinolysis regulated by vascular cells in different manners among cell types and the individual cell types respond to cadmium and lead in different manners with respect to the release of fibrinolytic proteins.

Cadmium↗

Chiral recognition of cellulose tris(5-fluoro-2-methylpheylcarbamate) toward (R)- and (S)-1, 1'-bi-2-naphthol detected by negative ion fast-atom bombardment mass spectrometry

Chiral recognition between cellulose tris(5-fluoro-2-methylphenylcarbamate) (MW > 120,000) as a host compound and (R,S)-1,1'-binaphthol (MW 286) as a guest compound was investigated by fast-atom bombardment mass spectrometry (FAB-MS). The use of negative ion FAB-MS made it possible to obtain a very simple mass spectrum of the guest compound with a high signal-to-noise ratio. Additionally, when nitrophenyl octyl ether, which has no OH group, was utilized as matrix, chiral recognition between the host and the guest compounds was unequivocally detected. Copyright 1999 John Wiley & Sons, Ltd.

Journal Article↗

Adult and geriatric normative data and validation of the profile of mood states.

The Profile of Mood States (POMS; McNair, Lorr, & Droppleman) is widely used to assess mood states. However, the utility of the POMS has been restricted by the lack of normative data from the general population. We report on our adult (N = 400) and geriatric (N = 170) POMS standardization samples. Both groups were age-, gender-, and race-stratified according to 1990 census data. We also report on convergent and discriminant validity of POMS scales, using a multitrait, multimethod paradigm.

Adolescent↗

Contribution of P-glycoprotein to bunitrolol efflux across blood-brain barrier.

In this study, we investigated the mechanism of the blood-brain barrier (BBB) transport of bunitrolol (BTL), as a model of beta-blocker, in vivo and in vitro. In order to define the contribution of P-glycoprotein (P-gp) to the active efflux of BTL from brain to blood, we examined the in vivo brain distribution of BTL in mdr1a(-/-) mice with a disrupted mdr1a gene. After intravenous administration of BTL to mdr1a(-/-) mice, the brain concentration and Kp value of BTL were significantly increased as compared with those in mdr1a(+/+) mice. Next, the contribution of the mdr1a P-gp to in vitro uptake of BTL was compared in LV500 cells and L cells (mouse mdr1a-expressing cells and host cells, respectively). The intracellular accumulations of [3H]vinblastine and BTL by LV500 cells were lower than those by L cells, but were significantly increased by verapamil, a P-gp inhibitor. Furthermore, the BTL uptake by KB-VJ300 cells, which express human P-gp, was also significantly lower than that by KB host cells, and was increased by verapamil. The steady-state uptake of BTL by LLC-GA5-COL300 cells, expressing human P-gp, was significantly increased in the presence of 20 microM cyclosporin A (another P-gp inhibitor), which had no effect in the LLC-PK1 host cells. On the other hand, the steady-state intracellular accumulation of BTL by MBEC4 cells, which express mdr1b P-gp instead of mdr1a P-gp, was not significantly changed in the presence of verapamil. This finding suggested that BTL is not a good substrate for mdr1b P-gp. In conclusion, our results suggest that BTL is transported from brain to blood by mdr1a P-gp in mice and by MDR1 in humans, and this presumably accounts for the low brain distribution of BTL.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Cycloprodigiosin hydrochloride, a new H(+)/Cl(-) symporter, induces apoptosis in human and rat hepatocellular cancer cell lines in vitro and inhibits the growth of hepatocellular carcinoma xenografts in nude mice.

The effects of cycloprodigiosin hydrochloride (cPrG-HCl), a new H(+)/Cl(-) symporter, were examined in liver cancer cell lines in vitro and in vivo. In the in vitro MTT assay, cPrG-HCl inhibited the growth of 6 liver cancer cell lines (Huh-7, HCC-M, HCC-T, dRLh-84, and H-35, hepatocellular carcinoma; HepG2, hepatoblastoma) in a dose- and time-dependent manner. The 50% inhibitory concentrations (IC(50)) at 72 hours' treatment for liver cancer cell lines were 276 to 592 nmol/L, while that for isolated normal rat hepatocyte was 8.4 micromol/L. The cPrG-HCl treatment of Huh-7 cells induced apoptosis as confirmed by the appearance of a subG(1) population, intranucleosomal DNA fragmentation, and chromatin condensation. cPrG-HCl raised the pH of acidic organelles and lowered pHi (below pH 6.8). In addition, the apoptosis in Huh-7 cells induced by cPrG-HCl was strongly suppressed when the cells were cultured with imidazole, a cell-permeable base. In the in vivo assay, nude mice bearing subcutaneous xenografted Huh-7 cells received 2 weeks of treatment with cPrG-HCl (1 or 10 mg/kg/d) subcutaneously. This treatment significantly inhibited tumor growth compared with the control after 8 days. The control mice were treated with 1% dimethylsulfoxide (DMSO) in saline (vehicle). A histopathological examination using the terminal deoxynucleotidyl transferase mediated dUTP biotin nick end labeling (TUNEL) method showed apoptosis in the treated tumor cells. No pathological changes were observed in any organs, and the serum alanine transaminase levels remained within normal limits. These results suggest that cPrG-HCl may be useful for the treatment of hepatocellular carcinoma.

Animals↗

Down-regulation of TGF-beta receptors in human colorectal cancer: implications for cancer development.

Many colorectal cancer cells are resistant to the anti-proliferative effects of transforming growth factor-beta (TGF-beta). TGF-beta also acts as paracrine factor from cancer cells on their mesenchymal cells. The aim of this study was to examine the expression of TGF-beta and its receptors in human colorectal cancer tissue and determine any relationship with cancer growth. In situ hybridization and Northern blot hybridization detection of TGF-beta1, type I and type II receptor mRNA and immunohistochemical staining of TGF-beta1 were performed using 11 human colorectal adenomas, 22 colorectal cancers and ten normal colorectal mucosas as control. TGF-beta receptor mRNAs were expressed mainly by normal colorectal epithelial cells and adenoma. However, mRNAs for TGF-beta receptors were only faintly, if at all, expressed in eight of 22 human colorectal cancers. In addition, intense signals of TGF-beta1 mRNA and the protein were detected in all colorectal cancers. TGF-beta receptor mRNAs and TGF-beta1 protein were also distributed in fibroblasts and endothelial cells in the interstitium. Moreover, Smad 4 protein was translocated to nucleus in primarily cultured adenoma cells, but not in cancer cells after TGF-beta stimulation. The escape of human colon cancer from TGF-beta-mediated growth inhibition by down-regulation of TGF-beta receptors as well as the effects of TGF-beta on stroma formation and angiogenesis indicate a possible role for TGF-beta in the progression of colon cancer in an intact host.

Adenoma↗

Physical and psychological improvements after phase II cardiac rehabilitation in patients with myocardial infarction.

We have designed a new 4-week hospitalized phase II cardiac rehabilitation program. The purpose of the present study is to clarify whether the physical and psychological status of patients with myocardial infarction (MI) improves after participation in our program. Twenty-nine patients (27 males, two females) with acute MI who enrolled in the 4-week hospitalized phase II rehabilitation program were assessed. All patients enrolled in this study had received coronary interventions. The rehabilitation consisted of exercise training, education and counseling. We evaluated the physical and psychological status of the patients before and just after the program, and at a 6-month follow up. The physical status was assessed by exercise tolerance measured by the peak oxygen consumption and anaerobic threshold, frequency of exercise, and serum concentrations of triglyceride, total cholesterol, high-density lipoprotein-cholesterol, and low-density lipoprotein-cholesterol. The psychological status was assessed by the Spielberger state-trait anxiety inventory questionnaire (STAI) and the self-rating questionnaire for depression (SRQ-D). Thirty-four patients (27 men, seven women) with MI who did not participate in our rehabilitation program served as a control group. After participation in our rehabilitation program, exercise tolerance and the serum lipid profiles of the patients were improved compared with those before rehabilitation. These parameters had improved significantly 6 months after rehabilitation. The STAI anxiety score was improved significantly and the SRQ-D depression score tended to be improved just after the rehabilitation program. Regular physical activity was continued even 6 months after the completion of the program. Our hospitalized phase II cardiac rehabilitation program improved the management of cardiac risk factors and the psychological status in patients with MI. This comprehensive program may contribute to the secondary prevention of MI as well as the recovery of physical and psychological activities.

Adult↗

[A study of factors relating to aggravation of patients with pulmonary Mycobacterium avium complex disease--with special reference to malnutrition].

We examined physical and blood statuses of 24 patients with pulmonary M. avium complex disease who entered our hospital from April 1993 to March 1997. Ten patients (41.7%) were diagnosed as primary infection type and 14 patients (58.3%) as secondary infection type. Twenty-four patients were classified to the following two groups: Group A was 14 patients who converted to MAC negative within six months after the admission and group B was 10 patients who continued to excrete MAC for more than six months after the admission. We made a comparison between group A and group B as to the results of physical and blood examinations on admission. Mean value of %IBW in group B was significantly lower (group B:74.4 +/- 8.9%, group A:82.9 +/- 12.7%, p < 0.05) than that of group A. The level of serum albumin in group B was significantly lower (group B: 3.39 +/- 0.53 g/dl, group A: 3.99 +/- 0.45 g/dl, p < 0.01) than that of group A. ChE in group B was significantly lower (group B: 321.2 +/- 94.5 IU/l, group A: 442.9 +/- 148.4 IU/l, p < 0.05) than that of group A. Group B was nutritionally depleted than group A. In conclusion, these findings suggested that nutritional support should be taken into consideration in combination with conventional chemotherapy in treating chronic, intractable MAC disease.

Aged↗

[Haemophilus parainfluenzae and IgA nephropathy].

IgA nephropathy (IgAN) was first reported by Berger in 1968, and characterized by diffuse IgA deposition in the mesangium. Patients with IgAN have usually episodic macroscopic hematuria accompanied with pharyngitis, gastroenteritis, bronchitis, or sinusitis. These findings suggest that IgAN is an immune-complex disease resulting from a poorly controlled mucosal immune response to environmental antigens to which the patient was chronically exposed. We reported the glomerular deposition of the outer membrane of Haemophilus parainfluenzae (OMHP) antigens and the presence of IgA antibody against OMHP in the sera of patients with IgAN. These suggest that Haemophilus parainfluenzae plays a role in the aetiology of this disease. This study was conducted to determine whether OMHP antigens induced immunohistologically evident glomerular deposition of IgA and C3 in C3H/HeN mice. Female C3H/HeN mice (4 weeks old) received intraperitoneal injection (HP-IP group), and oral administration (HP-PO group) of OMHP antigens. The control group similarly received intraperitoneal injection of PBS, and oral intake of ordinary water. The mice were sacrificed at 10, 20, 30, 40, 50 weeks after the start of the experiment. The HP-IP group showed glomerular deposition of IgA, C3 and OMHP antigens, glomerular changes (Mesangial hypercellularity and increase in mesangial matrix) after 20 weeks. The HP-PO group showed only mild deposition of IgA, and mild increase in mesangial matrix. These results suggest that OMHP antigens play a role in the glomerular deposition of IgA and C3 in C3H/HeN mice. This is the first use of OMHP antigens to establish an active model of IgAN.

Animals↗

Distribution and properties of kainate receptors distinct in the CA3 region of the hippocampus of the guinea pig.

To characterize the nature of kainate (KA) receptors distinct in the CA3 region of the hippocampus, properties of depolarizations induced by pulses of KA or AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate) applied to dendrites of CA3 neurons with micropipettes were studied in thin transverse slices of the guinea pig hippocampus. KA induced depolarizations at negligible latencies only when administered to the most proximal dendritic areas. The depolarization was unaffected by tetrodotoxin or by a decrease in Ca2+ and an increase in Mg2+ concentrations. The declining slope of the KA-induced depolarization was significantly slower than that of the AMPA-induced depolarization. In comparison with the AMPA-induced depolarization, the KA-induced depolarization was much less susceptible to antagonists such as 6-cyano-7-nitroquinoxaline-2, 3-dione (CNQX) and 1-(4-aminophenyl)-4-methyl-7, 8-methylenedioxy-5H-2,3-benzodiazepine hydrochloride (GYKI52466). 6, 7,8,9-Tetrahydro-5-nitro-1H-benz[g]indole-2,3-dione-3-oxime (NS-102) and (2S,4R)-4-methylglutamate (SYM 2081) were without effects. The threshold concentration of pressure-ejected KA to induce depolarizations was about 200 nM. Excitatory postsynaptic potentials elicited by mossy fiber stimulation were more potently suppressed by CNQX than by GYKI52466. These results indicate that receptors responsible for the slow KA depolarization in the CA3 region of the hippocampus are not AMPA receptors but KA receptors. They are localized in the most proximal part of the apical dendrite and distinct from those observed in primary cultures of hippocampal neurons.

6-Cyano-7-nitroquinoxaline-2,3-dione↗

Immunolocalization of transforming growth factor beta during wound repair in rat retina after laser photocoagulation.

BACKGROUND: Scatter photocoagulation induces regression of retinal neovascularization, but the mechanism of its therapeutic effect is incompletely understood. To elucidate the mechanism of therapeutic effect of photocoagulation is the main focus of our research. We have already demonstrated basic fibroblast growth factor (bFGF) immunolocalization during retinal wound repair following laser photocoagulation. Transforming growth factor beta (TGF beta) reportedly inhibits endothelial cell growth and bFGF-induced cell proliferation in vitro. In the present study, we evaluated the immunohistochemical localization of TGF-beta 1 and -beta 2 during wound repair in the rat retina following laser photocoagulation. METHODS: Krypton laser photocoagulation was performed on the eyes of pigmented rats. The eyes were then enucleated on day 1, 3, 7, 14, 28 or 56 following the photocoagulation and enrolled into the analysis of immunohistochemical localization of TGF-beta 1 and -beta 2. RESULTS: Immunoreactivity for TGF-beta 1 and -beta 2 was present in the ganglion cell layer and photoreceptor outer segments of the normal adult rat retina. The cytoplasm of RPE cells at the photocoagulated lesion showed intense TGF-beta 1 and -beta 2 immunoreactivity on day 3 after laser photocoagulation. Macrophages that migrated into the lesion lacked positive staining for TGF-beta 1 and -beta 2. TGF-beta immunoreactivity in RPE cells continued to be upregulated for more than 1 month compared with that in normal RPE cells. Controls did not exhibit any positive staining. CONCLUSION: An elevated expression of TGF-beta immunoreactivity for a longer period of time than bFGF was observed in RPE cells at the photocoagulated lesion in vivo. In the late phase of retinal wound repair, TGF-beta may inhibit cell proliferation induced by mitogens, introduce an end stage of cellular events, and induce extracellular matrix induction.

Animals↗

Expression of basic fibroblast growth factor and its receptor mRNA in retinal tissue following ischemic injury in the rat.

BACKGROUND: Our purpose was to determine the time-dependent changes of expression of basic fibroblast growth factor (bFGF) and its receptor in pressure-induced retinal ischemia in rats. METHODS: Retinal ischemia was induced in Wistar rats by increasing the intraocular pressure to 110 mmHg for 45 min by cannulation into the eyes. At the end of the ischemic period, reperfusion of the retinal vasculature was confirmed. Localization of bFGF and FGF receptor-1 (FGF-R) mRNAs were evaluated by in situ hybridization at various times after reperfusion. The reverse-transcription polymerase chain reaction (RT-PCR) method was used to detect the expression of bFGF and FGF-R mRNA in the sensory retina. RESULTS: In normal sensory retina, bFGF and FGF-R mRNAs were observed in the ganglion cell layer and inner nuclear layer. bFGF gene expression in the sensory retina increased within 24 h, particularly at 6-12 h. FGF-R gene expression increased earlier than that of bFGF. By RT-PCR, expression of bFGF gene reached a peak at 6-24 h, and FGF-R reached a peak at 3-12 h. These RT-PCR results are comparable to those of in situ hybridization. CONCLUSIONS: These results demonstrate that transient retinal ischemia leads to the induction of bFGF mRNA synthesis, and suggest that bFGF has a protective role, e.g., a defense mechanism for the sensory retina.

Animals↗