Biomedical subjects

T Shibata

Publications and source records attributed to T Shibata.

At least 199 records · Page 11Linked to original sources

PubMed1999

Outcomes of surgical treatment for cervical myelopathy in patients more than 75 years of age.

STUDY DESIGN: Retrospective study on the results of surgical treatment of compressive cervical myelopathy in patients more than 75 years of age. OBJECTIVES: To investigate clinical features and surgical outcomes of compressive cervical myelopathy in aged patients and to discuss the role of surgical treatment. SUMMARY OF BACKGROUND DATA: There are few data focused on the outcomes of surgery in patients with cervical myelopathy who are more than 75 years of age. METHODS: Seventeen patients with compressive cervical myelopathy who underwent surgery were reviewed. The average age at the time of surgery was 77.2 years. Posterior decompression in 15 patients and anterior decompression in 2 patients were performed. Neurologic deficits before and after surgery were assessed using a scoring system proposed by the Japanese Orthopaedic Association (JOA score). Independence of daily living was evaluated. Radiologic features were examined with radiographs and magnetic resonance imaging. Clinical results were compared with those of patients less than 65 years old as a control. RESULTS: The preoperative mean JOA score was 6.1, the postoperative maximum JOA scores averaged 11.4, and the recovery rate was 48.4%. These were significantly inferior to scores in those less than 65 years of age. All seven of the patients who could not walk even with aids before surgery became independent in daily activities after surgery. At the final follow-up, the mean JOA score had decreased to 10.7 and the recovery rate to 39.1%. Five of nine patients whose follow-up periods were more than 5 years showed decreases in JOA score, although all patients were still ambulatory. CONCLUSIONS: Surgical decompression for cervical myelopathy appears to be beneficial, even in patients more than 75 years of age, in improving neurologic function and ability to engage in activities of daily living.

Activities of Daily Living↗

PubMed1999

Two distinct mechanisms operate in the reactivation of heat-denatured proteins by the mitochondrial Hsp70/Mdj1p/Yge1p chaperone system.

The yeast mitochondrial Hsp70, Ssc1p, functions as a molecular chaperone with its partner proteins, Mdj1p (DnaJ homologue) and Yge1p (GrpE homologue). We have purified a mature form of Ssc1p from yeast mitochondria and those of Mdj1p and Yge1p from Escherichia coli overexpresser cells. With these purified components of the mitochondrial Hsp70 chaperone system, we have succeeded in reconstituting their chaperone functions in the protection of firefly luciferase against thermal damage in vitro. Heat-denatured luciferase is prevented from irreversible aggregation and is maintained in a refolding-competent state by Ssc1p and/or Mdj1p at 42 degreesC. Luciferase denatured at 42 degreesC is actively reactivated by Ssc1p, Mdj1p and/or Yge1p after lowering the temperature to 25 degreesC. The reactivation process of heat-denatured luciferase shows two-phase kinetics. The slow refolding process requires either Ssc1p or Mdj1p at 42 degreesC but the presence of Ssc1p, Mdj1p and Yge1p, and ATP hydrolysis, is essential at 25 degreesC. The slow refolding of luciferase involves multiple rounds of formation and dissociation of the complex between luciferase and Mdj1p/Ssc1p. On the other hand, the fast refolding process is most enhanced when luciferase is incubated with Ssc1p alone at 42 degreesC, and it requires neither the assistance of Mdj1p and Yge1p nor ATP hydrolysis. We have observed a similar two-pathway reactivation of heat-denatured luciferase by the bacterial Hsp70 and the yeast cytosolic Hsp70 systems.

Adenosine Triphosphate↗

PubMed1999

Nuclear magnetic resonance and molecular dynamics studies on the interactions of the Ras-binding domain of Raf-1 with wild-type and mutant Ras proteins.

The Ras protein and its homolog, Rap1A, have an identical "effector region" (residues 32-40) preceded by Asp30-Glu31 and Glu30-Lys31, respectively. In the complex of the "Ras-like" E30D/K31E mutant Rap1A with the Ras-binding domain (RBD), residues 51-131 of Raf-1, Glu31 in Rap1A forms a tight salt bridge with Lys84 in Raf-1. However, we have recently found that Raf-1 RBD binding of Ras is indeed reduced by the E31K mutation, but is not affected by the E31A mutation. Here, the "Rap1A-like" D30E/E31K mutant of Ras was prepared and shown to bind the Raf-1 RBD less strongly than wild-type Ras, but slightly more tightly than the E31K mutant. The backbone 1H, 13C, and 15N magnetic resonances of the Raf-1 RBD were assigned in complexes with the wild-type and D30E/E31K mutant Ras proteins in the guanosine 5'-O-(beta,gamma-imidotriphosphate)-bound form. The Lys84 residue in the Raf-1 RBD exhibited a large change in chemical shift upon binding wild-type Ras, suggesting that Lys84 interacts with wild-type Ras. The D30E/E31K mutant of Ras caused nearly the same perturbations in Raf-1 chemical shifts, including that of Lys84. We hypothesized that Glu31 in Ras may not be the major salt bridge partner of Lys84 in Raf-1. A molecular dynamics simulation of a model structure of the Raf-1 RBD.Ras.GTP complex suggested that Lys84 in Raf-1 might instead form a tight salt bridge with Asp33 in Ras. Consistent with this, the D33A mutation in Ras greatly reduced its Raf-I RBD binding activity. We conclude that the major salt bridge partner of Lys84 in Raf-1 may be Asp33 in Ras.

Amino Acid Sequence↗

PubMed1999

Different expressions of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid and N-methyl-D-aspartate receptor subunit mRNAs between visceromotor and somatomotor neurons of the rat lumbosacral spinal cord.

The glutamatergic transmission system plays a key role in afferent and efferent pathways involved in micturition. By in situ hybridization combined with retrograde Fast Blue labeling, expression of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor (GluR-A to -D) and N-methyl-D-aspartate (NMDA) receptor (NR1 and NR2A-D) subunit mRNAs were examined in visceromotor and somatomotor neurons of the rat lumbosacral spinal cord. Parasympathetic preganglionic neurons (PGNs) in the intermediolateral nucleus highly expressed GluR-A and GluR-B subunit mRNAs, with very low levels for GluR-C and GluR-D subunits. As for the NMDA receptor, PGNs were associated with abundant signals for NR1 subunit mRNA, but without any NR2 subunit mRNAs. On the other hand, somatomotor neurons in the ventral horn (dorsolateral nucleus) express all four AMPA receptor subunit mRNAs, showing relatively abundant expressions of GluR-C and GluR-D subunit mRNA compared with PGNs. In addition to high levels of NR1 subunit mRNA, dorsolateral nucleus neurons moderately expressed NR2A and NR2B subunit mRNAs. These results suggest that molecular organization of both AMPA and NMDA receptor channels are distinct between PGNs and dorsolateral nucleus neurons. Considering that native NMDA receptors are heteromeric channels composed of NR1 and NR2 subunits, it seems likely that dorsolateral nucleus neurons, not PGNs, are provided with functional NMDA receptors, which could induce activity-dependent changes in synaptic transmission in the efferent pathway for the lower urinary tract.

Amidines↗

PubMed1999

Pharmacological profiles of a novel oral antidiabetic agent, JTT-501, an isoxazolidinedione derivative.

JTT-501, 4-[4-[2-(5-methyl-2-phenyl-4-oxazolyl)ethoxy]benzyl]-3,5-isoxaz olidinedione, is an isoxazolidinedione derivative which is structurally distinct from thiazolidinediones such as pioglitazone and troglitazone. We investigated the effects of JTT-501 on insulin-sensitizing activity and in rodent diabetic models. JTT-501 enhanced insulin-stimulated cell differentiation of 3T3-L1 fibroblasts with an EC50 value of 110 nM. Furthermore, JTT-501 activated peroxisome proliferator-activated (PPA) gamma and alpha receptors with the EC5-fold values of 0.28 and 5.4 microM, respectively. In the non-insulin-dependent diabetes mellitus model KK-Ay mice, JTT-501 improved hyperglycemia, hyperinsulinemia and hypertriglyceridemia, and enhanced insulin-stimulated glucose oxidation in adipose tissues. JTT-501 was also effective in the non-insulin-dependent diabetes mellitus model Zucker diabetic fatty (ZDF) rats but not in the insulin-dependent diabetes mellitus model streptozotocin-induced diabetic mice. These observations suggest that JTT-501 enhances insulin sensitivity in peripheral tissues and improves hyperglycemia, hyperinsulinemia, and hypertriglyceridemia in non-insulin dependent diabetes mellitus models. In particular, the triglyceride-lowering activity of JTT-501 is a unique characteristic compared to the thiazolidinediones. Therefore, JTT-501 may be a promising antidiabetic agent for treating non-insulin-dependent diabetes mellitus patients with insulin resistance.

3T3 Cells↗

PubMed1999

Cell-free production and stable-isotope labeling of milligram quantities of proteins.

We have improved the productivity of an Escherichia coli cell-free protein synthesis system. First, creatine phosphate and creatine kinase were used as the energy source regeneration system, and the other components of the reaction mixture were optimized. Second, the E. coli S30 cell extract was condensed by dialysis against a polyethylene glycol solution to increase the rate of synthesis. Third, during the protein synthesis, the reaction mixture was dialyzed against a low-molecular-weight substrate solution to prolong the reaction. Thus, the yield of chloramphenicol acetyltransferase was raised to 6 mg/ml of reaction mixture. Stable-isotope labeling of a protein with 13C/15N-labeled amino acids for NMR spectroscopy was achieved by this method.

Biotechnology↗

PubMed1999

Systematic identification, classification, and characterization of the open reading frames which encode novel helicase-related proteins in Saccharomyces cerevisiae by gene disruption and Northern analysis.

Helicase-related proteins play important roles in various cellular processes incuding DNA replication, DNA repair, RNA processing and so on. It has been well known that the amino acid sequences of these proteins contain several conserved motifs, and that the open reading frames (ORFs) which encode helicase-related proteins make up several gene families. In this study, we have identified 134 ORFs that encode helicase-like proteins in the Saccharomyces genome, based on similarity with the ORFs of authentic helicase and helicase-related proteins. Multiple alignment of the ORF sequences resulted in the 134 ORFs being classified to 11 clusters. Seven out of 21 previously uncharacterized ORFs (YDL031w, YDL070w, YDL084w, YGL150c, YKL078w, YLR276c, and YMR128w) were identified by systematic gene disruption, to be essential for vegetative growth. Three (YDR332w, YGL064c, and YOL095c) out of the remaining 14 dispensable ORFs exhibited the slow-growth phenotype at 30 degrees C and 37 degrees C. Furthermore, the expression profiles of transcripts from 43 ORFs were examined under seven different growth conditions by Northern analysis and reverse transcription-polymerase chain reaction, indicating that all of the 43 tested ORFs were transcribed. Interestingly, we found that the level of transcript from 34 helicase-like genes was markedly increased by heat shock. This suggests that helicase-like genes may be involved in the biosynthesis of nucleic acids and proteins, and that the genes can be transcriptionally activated by heat shock to compensate for the repressed synthesis of mRNA and protein.

Amino Acid Sequence↗

PubMed1999

Application of intravascular ultrasonography for intracaval tumor thrombectomies in adrenal metastasis from hepatocellular carcinoma: report of two cases.

Intracaval tumor thrombus is one of the characteristic features of advanced hepatocellular carcinoma. To formulate an appropriate operative strategy for removing intracaval tumor thrombi, it is of great importance to accurately diagnose the location, any invasion into the wall of the vena cava, and the extent of intracaval tumor spread. Intravascular ultrasonographic imaging is a novel technology that enables the precise catheter-based assessment of the dimensions and morphology of the vascular structure and any lesions. We have applied this technology to the diagnosis of intracaval tumor thrombi originating from adrenal metastasis secondary to hepatocellular carcinomas. This modality was thus found to be useful in determining the best operative procedure for removing tumor thrombi in the inferior vena cava.

Adrenal Gland Neoplasms↗

PubMed1999

A new antidiabetic agent (JTT-501) rapidly stimulates glucose disposal rates by enhancing insulin signal transduction in skeletal muscle.

A newly synthesized antidiabetic agent, JTT-501 is an isoxazolidinedione rather than a thiazolidinedione. An oral dose of JTT-501 (100 mg x kg(-1) x day(-1)) given to 12-week-old male Zucker fatty rats for 7 days led to the amelioration of both hyperinsulinaemia (40% of non-treated) and hypertriglyceridaemia (23% of non-treated) as well as a 2.4-fold increased insulin sensitivity as determined by a euglycaemic insulin clamp. In our study, we further evaluated the acute effect of JTT-501 on both the glucose infusion rates (GIR) and insulin signalling in skeletal muscle. Male Sprague-Dawley (SD) rats aged 10 weeks were injected intravenously with JTT-501 (5 mg/kg) and then a euglycaemic insulin clamp was initiated and glucose infusion rates monitored for 150 min. We found that this treatment increased the glucose infusion rate by 33% during the last 30 min in SD rats. After the clamp had been initiated for 30 min, the insulin-stimulated phosphatidylinositol 3-kinase (PI3-kinase) activities co-immunoprecipitated with insulin receptor substrate 1 (IRS-1) were also enhanced, resulting in increased glycogen synthase activities in the soleus muscles. Treatment with JTT-501 also enhanced the phosphorylation of insulin receptors and insulin receptor-substrate 1 rapidly as well as the phosphatidylinositol 3-kinase activities, which were stimulated by a bolus injection of insulin. Similarly, JTT-501 stimulated the glucose infusion rate by 30% and enhanced insulin signalling in Zucker fatty rats. In conclusion, a newly developed isoxazolidinedione, JTT-501, rapidly potentiates the insulin sensitivity of skeletal muscle by enhancing insulin signalling and could be useful for the treatment of insulin-resistant diabetic subjects.

Animals↗

PubMed1999

A mutation in a mitochondrial ABC transporter results in mitochondrial dysfunction through oxidative damage of mitochondrial DNA.

We have isolated a Saccharomyces cerevisiae mutant that shows an increased tendency to form cytoplasmic petites (respiration-deficient rho- or rho0 mutants) in response to treatment of cells growing on a solid medium with the DNA-damaging agent methyl methane-sulfonate or ultraviolet light. The mutation in this strain, atm1-1, was found to cause a single amino acid substitution in ATM1, a nuclear gene that encodes the mitochondrial ATP-binding cassette (ABC) transporter. When the mutant cells were grown in liquid glucose medium, they accumulated free iron within the mitochondria and at the same time gave rise to spontaneous cytoplasmic petite mutants, as seen previously in cells carrying a mutation in a gene homologous to the human gene responsible for Friedreich's ataxia. Analysis of the effects of free iron and malonic acid (an inhibitor of oxidative respiration in mitochondria) on the incidence of petites among the mutant cells indicated that spontaneous induction of petites was a consequence of oxidative stress rather than a direct effect of either a defect in the ATM1 gene or the accumulation of free iron. We observed an increase in the incidence of strand breaks in the mitochondrial DNA of the atm1-1 mutant cells. Furthermore, we found that rates of induction of petites and accumulation of strand breaks in mitochondrial DNA were enhanced in the atm1-1 mutant by the introduction of another mutation, mhr1-1, which results in a deficiency in mitochondrial DNA repair. These observations indicate that spontaneous induction of petites in the atm1-1 mutant is a consequence of oxidative damage to mitochondrial DNA mediated by enhanced accumulation of mitochondrial iron.

ATP-Binding Cassette Transporters↗

PubMed1999

Capillary changes with fenestrations in the contralateral soleus muscle of the rat following unilateral limb immobilization.

Using electron microscopy, we examined structural changes in the capillaries of the immobilized and contralateral soleus muscles in the rat after the unilateral limb had been immobilized for 4 weeks. Individual contralateral muscle fibers showed a normal structure, compared with the structure in the immobilized muscle fibers. Most capillaries in the contralateral muscle were of the continuous type. However, about 5% of the examined capillaries in these muscles in each rat had fenestrations. The non-nuclear portions of the endothelial cells in these capillaries were extremely thin and were perforated by several fenestrations that were bridged by a single-layered diaphragm. The fenestration of capillaries in the contralateral muscle may have been caused by some the unilateral limb immobilization.

Animals↗

PubMed1999

Stuck valve leaflet detected by intraoperative transesophageal echocardiography.

We encountered a rare complication of mitral valve replacement with the CarboMedics prosthesis: a "stuck" leaflet detected by transesophageal echocardiography even though weaning from cardiopulmonary bypass had been uneventful. The patient was immediately managed without significant problems. We emphasize the importance of performing routine intraoperative transesophageal echocardiography in valve replacement as well as in valve repair, from the initial phase of operation.

Echocardiography, Transesophageal↗

PubMed1999

Coagulofibrinolysis during heparin-coated cardiopulmonary bypass with reduced heparinization.

BACKGROUND: We examined the safety of reduced systemic heparinization during heparin-coated cardiopulmonary bypass by measuring coagulofibrinolitic indices, including fibrinopeptide A, which directly reflects fibrinogenesis. METHODS: Twenty-four patients who had elective cardiac operations were perfused using a circuit coated with covalently bonded heparin. Twelve patients received 300 U/kg of heparin and the remaining 12 patients received 150 U/kg. Blood was obtained for the measurement of thrombin-antithrombin III complexes, fibrinopeptide A, plasmin-alpha 2 plasmin inhibitor complexes, and D-dimer preoperatively; after heparin administration; 10, 60, and 90 minutes after the start of bypass; after protamine administration; and 1, 3, 6, 12, and 24 hours after the end of bypass. RESULTS: Preoperative, intraoperative, and postoperative variables including postoperative bleeding were not significantly different between the two groups. Further, there were no complications in either group. No significant differences between the two groups were noted for any hematologic index at any time point. CONCLUSIONS: Reduced systemic heparinization combined with a heparin-coated cardiopulmonary bypass circuit is biochemically and clinically safe but does not reduce postoperative bleeding.

Adult↗

PubMed1999

The relevance of urethral resistance in children with myelodysplasia: its impact on upper urinary tract deterioration and the outcome of conservative management.

PURPOSE: Upper urinary tract deterioration, such as vesicoureteral reflux and hydronephrosis, affects the long-term prognosis in children with myelodysplasia. We retrospectively analyzed the relevance of urethral resistance to upper tract deterioration in untreated children with myelodysplasia as well as the outcome of conservative treatment based on urethral resistance. MATERIALS AND METHODS: Included in our study were 32 boys and 29 girls with a mean age at presentation of 3.6 years and a mean followup of 9.2 years. The children were divided into group 1-31 with high and group 2-30 with low urethral resistance, as determined by leak point pressure or maximum urethral closing pressure. Clean intermittent catheterization with or without anticholinergics was instituted in all children in group 1 and those in group 2 with documented upper tract deterioration and/or problematic urinary incontinence after school age. We compared the incidence of upper tract deterioration at the initial evaluation and during followup as well as the final status of the upper tract in the 2 groups. RESULTS: At the initial evaluation 17 of 31 group 1 (55%) and 4 of 30 group 2 (13%) patients had upper tract deterioration (p <0.01). Deterioration was refractory to conservative management in 5 group 1 children who required bladder augmentation. The incidence of de novo upper tract deterioration during followup was not statistically different in the 2 groups (10 and 7% in groups 1 and 2, respectively). At the final evaluation the upper tract was normal in 26 (84%), improved in 3 and stable in 2 group 1 patients, while it was normal in 26 (87%) in group 2. CONCLUSIONS: Urethral resistance is relevant to upper tract deterioration in untreated children with myelodysplasia. Although bladder augmentation was necessary in some children with high urethral resistance, the outcome of conservative treatment was generally satisfactory with the preservation or normalization of the upper tract in more than 80% regardless of urethral resistance.

Adolescent↗

PubMed1999

Some interactions of L-DOPA and its related compounds with glutamate receptors.

L-DOPA is probably a transmitter and/or modulator in the central nervous system (1). L-DOPA methyl ester (DOPA ME) is a competitive L-DOPA antagonist. However, it remains to be clarified whether there exist L-DOPAergic receptors. In Xenopus laevis oocytes injected with rat brain poly(A)+ RNA, L-DOPA induced small inward currents with ED50 of 2.2 mM at a holding potential of -70 mV. The currents were abolished by kynurenic acid or CNQX. Similar L-DOPA-currents were seen in oocytes co-injected with AMPA receptors, GluRs1,2,3 and 4. In brain membrane preparations, L-DOPA inhibited specific binding of [3H]-AMPA with IC50 of 260 microM. This inhibition was not modified by 200 microM ascorbic acid, an antioxidant. L-DOPA did not inhibit binding of [3H]-ligands of MK-801, kainate, DCKA and CGP39653. DOPA ME and L-DOPA cyclohexyl ester, a novel, potent and competitive antagonist (2), inhibited specific binding of [3H]-MK-801 with respective IC50 of 1 and 0.68 mM, but elicited no effect on that of the other [3H]-ligands. With low affinities, L-DOPA acts on AMPA receptors, while competitive antagonists act on NMDA ion channel domain. L-DOPAergic agonist and antagonist may not interact on ionotropic glutamate receptors. DOPA ME-sensitive L-DOPA recognition sites (1) seem to differ from glutamate receptors.

2-Amino-5-phosphonovalerate↗

PubMed1999

Application of immunoaffinity chromatography for detection of tetrodotoxin from urine samples of poisoned patients.

Immunoaffinity chromatography using the monoclonal antibody (Tl-1) specific for tetrodotoxin (TTX) has been developed for isolating TTX from urine samples. By combining immunoaffinity chromatography with fluorometric high performance liquid chromatography (HPLC), it has become possible to detect a small amount of TTX in urine samples. The detection limit of TTX in urine was 2 ng/ml. By this combined method, TTX was detected in all the urine samples that were collected from poisoned patients during the week following TTX ingestion. The combination of immunoaffinity chromatography with HPLC was very useful in detecting TTX from the urine samples of poisoned patients for diagnosis of TTX-food poisoning.

Antibodies, Monoclonal↗

PubMed1999

Event-related dynamics of the gamma-band oscillation in the human brain: information processing during a GO/NOGO hand movement task.

To investigate the gamma band activity relating to the discrimination process and motor behavior in the human brain, the event-related dynamics of the EEG spectrum was calculated during the visual GO/NOGO hand movement task and a control task (the visual element of the GO/NOGO task only) in eight subjects. The subjects were instructed to push (GO) or not to push (NOGO) a microswitch according to different visual stimuli and 21-channel scalp EEGs were recorded. The time courses of the power spectra after the stimuli were calculated using the fast Fourier transform for each condition (GO, NOGO and the control task), and were compared statistically between the conditions. The results suggested that a high gamma band oscillation, occurring at the frontal and left parieto-occipital areas at around 90 ms after the stimuli, relates to the discrimination process. Under the GO condition, this oscillation continued until 140 ms, and a subsequent oscillation occurred over the motor areas at around 200 ms, which seemed to be related to the motor action. On the other hand, under the NOGO condition, a low gamma band oscillation occurred in the central area at around 230 ms, which seemed to be related to the inhibition process.

Adult↗

PubMed1999

Glucocorticoid-dependent induction of HMG-CoA reductase and malic enzyme gene expression by polychlorinated biphenyls in rat hepatocytes.

Administration of xenobiotics to rats results in hypercholesterolemia and in the induction of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase and malic enzyme. To investigate the mechanism of the induction of the enzymes by xenobiotics, the effects of xenobiotics on gene expressions for HMG-CoA reductase, malic enzyme, and cytochrome P-450 in rat liver and in cultured hepatocyte were investigated. The treatment of rats with polychlorinated biphenyls (PCB) as a xenobiotic induced mRNAs for HMG-CoA reductase and malic enzyme as well as CYP2B1/2 (cytochrome P-450b/e). Other xenobiotics, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT), and chloretone, also increased HMG-CoA reductase mRNA. In an investigation of diurnal rhythm of mRNA for HMG-CoA reductase, the induction by PCB was observed in a dark period. Induced expressions of HMG-CoA reductase gene and malic enzyme gene by PCB were observed in primary cultured rat hepatocytes and showed that the action of PCB on the gene expression relating to lipid metabolism was directed on hepatocytes. The induction was observed only in hepatocytes cultured on Engelbreth-Holm-Swarm sarcoma basement membrane gel (EHS-gel), not on type I collagen, which is usually used for monolayer culture of hepatocytes. The induction of CYP2B1/2 gene expression also was observed only in the cells cultured on EHS-gel. The induction of HMG-CoA reductase and malic enzyme by PCB required dexamethasone. However, the addition of dexamethasone per se to medium containing insulin did not show an inductive effect on levels of mRNA for HMG-CoA reductase and malic enzyme. From the data of diurnal variation and hepatocyte culture experiment, HMG-CoA reductase and malic enzyme are considered to be induced by PCB through the so-called "permissive effect" of glucocorticoid.

Journal Article↗