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Results for “Cationic Amino Acid Transporter 2”

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PubMed1996

Molecular cloning, tissue distribution, and chromosomal localization of human cationic amino acid transporter 2 (HCAT2).

Human cationic amino acid transporter 2 (HCAT2) was isolated from a human intestine cDNA library. The nucleotide sequence of the coding region predicts a 658-amino-acid protein with a calculated molecular weight of 71,669. As 91% of the residues are identical with those of the mouse cationic amino acid transporter 2 (MCAT2), HCAT2 seems to be a human counterpart of MCAT2. We found no isoform as was present in MCAT2. In Northern blot analysis, a single (9.0 kb) HCAT2 mRNA transcript was present in various human tissues. The highest level of expression was observed in skeletal muscle and the lowest level in the kidney. Hydropathy plots indicated that the translated protein is predicted to have 14 transmembrane domains with three potential N-glycosylation sites. Two patients with lysinuric protein intolerance (MIM No. 222700) were analyzed for HCAT2 cDNA but no mutation was detected. The HCAT2 gene was assigned to human chromosome 8p21.3-p22.

Amino Acid Metabolism, Inborn Errors↗

PubMed2006

Heme oxygenase 1, nuclear factor E2-related factor 2, and nuclear factor kappaB are involved in hemin inhibition of type 2 cationic amino acid transporter expression and L-Arginine transport in stimulated macrophages.

BACKGROUND: L-Arginine transport mediated by type 2 cationic amino acid transporter (CAT-2) is one crucial mechanism that regulates nitric oxide production mediated by inducible nitric oxide synthase. Heme oxygenase (HO)-1 induction has been reported to significantly attenuate inducible nitric oxide synthase expression and nitric oxide production. The authors sought to explore the effects of HO-1 induction on CAT-2 expression and L-arginine transport. The effects of HO-1 induction on nuclear factor E2-related factor 2 (Nrf2) and nuclear factor kappaB (NF-kappaB) were also investigated. METHODS: Murine macrophages (RAW264.7 cells) were randomized to receive lipopolysaccharide, lipopolysaccharide plus hemin (an HO-1 inducer; 5, 50, or 500 microm), lipopolysaccharide plus hemin (5, 50, or 500 microm) plus tin protoporphyrin (an HO-1 inhibitor), or lipopolysaccharide plus hemin (5, 50, or 500 microm) plus hemoglobin (a carbon monoxide scavenger). Then, cell cultures were harvested and analyzed. RESULTS: Lipopolysaccharide significantly induced Nrf2 activation and HO-1 expression. Lipopolysaccharide also significantly induced NF-kappaB activation, CAT-2 expression, and L-arginine transport. In a dose-dependent manner, hemin enhanced the lipopolysaccharide-induced Nrf2 activation and HO-1 expression. In contrast, hemin, also in a dose-dependent manner, significantly attenuated the lipopolysaccharide-induced NF-kappaB activation, CAT-2 expression, and L-arginine transport. Furthermore, the effects of hemin were significantly reversed by both tin protoporphyrin and hemoglobin. CONCLUSIONS: HO-1 induction significantly inhibited CAT-2 expression and L-arginine transport in lipopolysaccharide-stimulated macrophages, possibly through mechanisms involved activation of Nrf2 and inhibition of NF-kappaB. In addition, carbon monoxide mediated, at least in part, the effects of HO-1 induction on CAT-2 expression and L-arginine transport.

Animals↗

PubMed2006

Cationic amino acid transporter 2 regulates inflammatory homeostasis in the lung.

Arginine is an amino acid that serves as a substrate for nitric oxide synthase and arginase. As such, arginine has the potential to influence diverse fundamental processes in the lung. Here we report that the arginine transport protein, cationic amino acid transporter (CAT)2, has a critical role in regulating lung inflammatory responses. Analysis of CAT2-deficient mice revealed spontaneous inflammation in the lung. Marked eosinophilia, associated with up-regulation of eotaxin-1, was present in the bronchoalveolar lavage fluid of 3-week-old CAT2-deficient mice. The eosinophilia was gradually replaced by neutrophilia in adult mice, while eotaxin-1 levels decreased and GRO-alpha levels increased. Despite the presence of activated alveolar macrophages in CAT2-deficient mice, NO production was compromised in these cells. Examination of dendritic cell activation, which can be affected by NO release, indicated increased dendritic cell activation in the lungs of CAT2-deficient mice. This process was accompanied by an increase in the number of memory T cells. Thus, our data suggest that CAT2 regulates anti-inflammatory processes in the lungs via regulation of dendritic cell activation and subsequent T cell responses.

Animals↗

PubMed2006

Arginine transport via cationic amino acid transporter 2 plays a critical regulatory role in classical or alternative activation of macrophages.

Arginine is processed by macrophages in response to the cytokines to which these cells are exposed. Th1-type cytokines induce NO synthase 2, which metabolizes arginine into nitrites, while the Th2-type cytokines produce arginase, which converts arginine into polyamines and proline. Activation of bone marrow-derived macrophages by these two types of cytokines increases L-arginine transport only through the y(+) system. Analysis of the expression of the genes involved in this system showed that Slc7A1, encoding cationic amino acid transporters (CAT)1, is constitutively expressed and is not modified by activating agents, while Slc7A2, encoding CAT2, is induced during both classical and alternative activation. Macrophages from Slc7A2 knockout mice showed a decrease in L-arginine transport in response to the two kinds of cytokines. However, while NO synthase 2 and arginase expression were unmodified in these cells, the catabolism of arginine was impaired by both pathways, producing smaller amounts of nitrites and also of polyamines and proline. In addition, the induction of Slc7A2 expression was independent of the arginine available and of the enzymes that metabolize it. In conclusion, the increased arginine transport mediated by activators is strongly regulated by CAT2 expression, which could limit the function of macrophages.

Animals↗

PubMed2001

Differential expression of the cationic amino acid transporter 2(B) in the adult rat brain.

L-Arginine is a substrate for the synthesis of proteins, nitric oxide (NO), creatine, urea, proline, glutamate, polyamines and agmatine. In the central nervous system (CNS), arginine is extracted from the blood and exchanged by cells through carriers called cationic amino acid transporters (CAT) and belonging to the so-called system y+. In order to better understand the arginine transport in the CNS, we studied in detail the regional distribution of the cells expressing the CAT2(B) transcript in the adult rat brain by non-radioisotopic in situ hybridization. We show that CAT2(B) is expressed in neurons and oligodendrocytes throughout the brain, but is not detected in astrocytes. The pattern of localization of CAT2(B) in the normal adult rat brain fits closely that of CRT1, a specific creatine transporter. Our study demonstrates that the in vivo expression of CAT2(B) differs from that reported in vitro, implying that local cellular interactions should be taken into account in studies of gene regulation of the CAT2(B) gene. Our work suggests that CAT2(B) may play a role in case of increased NO production as well as arginine or creatine deficiency in the brain.

Age Factors↗

PubMed2003

The importance of cationic amino acid transporter expression in human skin.

Inducible nitric oxide synthase and arginase activities are acknowledged as important players in human skin epidermal function. For proper enzyme function the substrate availability of L-arginine for both enzymes and thus its transport across the cell membrane via the y+-system (also named cationic amino acid transporters) is critical. Here, we examine the expression of cationic amino acid transporters and their functional role in modulating inducible nitric oxide synthase and arginase activities in human skin and primary keratinocytes, fibroblasts and endothelial cells as well as their impact on keratinocyte proliferation. Skin biopsies were found to express constitutively both cationic amino acid transporter-1 and cationic amino acid transporter-2 mRNA, an expression pattern known to occur in hepatocytes and muscle cells only. To determine the cellular components expressing cationic amino acid transporter, we analyzed the expression patterns in the different human skin cell types in vitro, i.e., in fibroblasts, dermal endothelial cells, and keratinocytes as well as in the HaCaT cell line. An ubiquitous cationic amino acid transporter-1 mRNA expression was found in all cells, whereas constitutive cationic amino acid transporter-2 mRNA expression occurs in resident keratinocytes and dermal endothelial cells only. De novo induction of cationic amino acid transporter-2 and inducible nitric oxide synthase by proinflammatory cytokines was seen in fibroblasts and HaCaT. Competitive inhibition of the cationic amino acid transporter-mediated L-arginine transport by culturing primary human keratinocytes in the presence of increased L-lysine concentration led to decreased inducible nitric oxide synthase and arginase activities with a concomitant significant decrease in keratinocyte proliferation. In summary, our results demonstrate that human keratinocytes constitutively express cationic amino acid transporters 1 and 2 and that cationic amino acid transporter mediated L-arginine influx, is essential for both inducible nitric oxide synthase and arginase enzyme activities, which in turn modulate proliferation and differentiation of human epidermal skin cells.

Arginase↗

PubMed2005

Reduced bactericidal activity and nitric oxide production in metallothionein-deficient macrophages in response to lipopolysaccharide stimulation.

This study was designed to investigate bactericidal activity of and nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated peritoneal exudate macrophages (Mvarphi) from metallothionein (MT)-null mice. Control Mvarphi had a bactericidal effect on Staphylococcus aureus, but MT-null Mvarphi had significantly lower activity. NO is an important factor in the bactericidal function of Mvarphi. LPS-stimulated MT-null Mvarphi produced less NO than those of control mice. LPS-stimulated Mvarphi produce cytokines such as tumor necrosis factor (TNF)-alpha. TNF-alpha activate Mvarphi and stimulates NO production. We evaluated NO production by TNF-alpha-stimulated Mvarphi. MT-null Mvarphi produced less NO in response to TNF-alpha stimulation. Levels of expression of inducible NO synthase (iNOS) mRNA and production of iNOS protein in response to LPS stimulation were similar in MT-null and control cells, as were levels of expression of arginase, which competes in arginine metabolism with iNOS. No notable changes were found in arginine uptake or in expression of cationic amino acid transporter 2 (a major arginine transporter in Mvarphi) between control and MT-null Mvarphi. The rate of conversion of [(14)C]-l-arginine to citrulline, which is formed with NO by the action of iNOS, was much lower in MT-null Mvarphi than in control cells. These results indicate that the reduced production of NO in MT-deficient Mvarphi is due mainly to reduced activity of iNOS. Thus, MT plays important roles in bactericidal activity, NO production, and arginine metabolism in activated Mvarphi.

Animals↗

PubMed2005

Regulating gene expression through RNA nuclear retention.

Multiple mechanisms have evolved to regulate the eukaryotic genome. We have identified CTN-RNA, a mouse tissue-specific approximately 8 kb nuclear-retained poly(A)+ RNA that regulates the level of its protein-coding partner. CTN-RNA is transcribed from the protein-coding mouse cationic amino acid transporter 2 (mCAT2) gene through alternative promoter and poly(A) site usage. CTN-RNA is diffusely distributed in nuclei and is also localized to paraspeckles. The 3'UTR of CTN-RNA contains elements for adenosine-to-inosine editing, involved in its nuclear retention. Interestingly, knockdown of CTN-RNA also downregulates mCAT2 mRNA. Under stress, CTN-RNA is posttranscriptionally cleaved to produce protein-coding mCAT2 mRNA. Our findings reveal a role of the cell nucleus in harboring RNA molecules that are not immediately needed to produce proteins but whose cytoplasmic presence is rapidly required upon physiologic stress. This mechanism of action highlights an important paradigm for the role of a nuclear-retained stable RNA transcript in regulating gene expression.

3' Untranslated Regions↗

PubMed2003

CAT2 arginine transporter deficiency significantly reduces iNOS-mediated NO production in astrocytes.

We have previously demonstrated that genetic ablation of cationic amino acid transporter 2 (Cat2) significantly inhibits nitric oxide (NO) production by inducible nitric oxide synthase (iNOS) in activated macrophages. Here we report that iNOS activity is impaired by 84% in activated Cat2-deficient astrocytes. Cat2 ablation appears to reduce astrocyte NO synthesis by decreasing the uptake of the sole precursor, arginine, as well as by reducing the expression of iNOS following activation. Excessive or dysregulated NO production by activated astrocytes and other CNS cell types has been implicated in the pathogenesis of neurological disorders. Our results support the idea that manipulation of CAT2 transporter function might be useful for the therapeutic modulation of iNOS activity.

Amino Acid Transport System y+↗

PubMed1998

Cationic amino acid transporter mRNA expression in rat kidney and liver.

Expression of rat cationic amino acid transporter 2 (r-CAT-2) mRNA was studied in kidney and liver using Northern blot analysis and nonradioactive in situ hybridization with a probe identifying both the r-CAT-2alpha and -2beta splice variants. Expression of r-CAT-2 mRNA was higher in the liver than in the kidney. Within the kidney, r-CAT-2 mRNA was more abundant in the outer and inner medulla than in the cortex. In the liver lobule, the intensity of the hybridization signal in hepatocytes decreased between the portal area and the central vein. In the kidney, hybridization signals were detected in parietal cells of Bowman's capsule, various tubule cells of outer and inner medulla, in endothelial and interstitial cells of inner medulla, and in papillary epithelial cells.

Amino Acid Transport Systems, Basic↗

PubMed2004

The stimulation of arginine transport by TNFalpha in human endothelial cells depends on NF-kappaB activation.

In human saphenous vein endothelial cells (HSVECs), tumor necrosis factor-alpha (TNFalpha) and bacterial lipopolysaccharide (LPS), but neither interferon gamma (IFNgamma) nor interleukin 1beta (IL-1beta), stimulate arginine transport. The effects of TNFalpha and LPS are due solely to the enhancement of system y+ activity, whereas system y+L is substantially unaffected. TNFalpha causes an increased expression of SLC7A2/CAT-2B gene while SLC7A1/CAT-1 expression is not altered by the cytokine. The suppression of PKC-dependent transduction pathways, obtained with the inhibitor chelerytrhine, the inhibitor peptide of PKCzeta isoform, or chronic exposure to phorbol esters, does not prevent TNFalpha effect on arginine transport. Likewise, ERK, JNK, and p38 MAP kinases are not involved in the cytokine effect, since arginine transport stimulation is unaffected by their specific inhibitors. On the contrary, inhibitors of NF-kappaB pathway hinder the increase in CAT2B mRNA and the stimulation of arginine uptake. These results indicate that in human endothelial cells the activation of NF-kappaB pathway mediates the TNFalpha effects on arginine transport.

Amino Acid Transport Systems, Basic↗

PubMed1999

Regulation of the genes for arginase isoforms and related enzymes in mouse macrophages by lipopolysaccharide.

Arginase exists in two isoforms, the hepatic (arginase I) and extrahepatic types (arginase II). Arginase I is markedly induced in rat peritoneal macrophages and rat tissues in vivo by bacterial lipopolysaccharide (LPS). In contrast, both arginase I and arginase II are induced in LPS-activated mouse peritoneal macrophages. In the present study, expression of arginase isoforms and related enzymes was studied in mouse tissues in vivo and in peritoneal macrophages with RNA blot and immunoblot analyses and enzyme assay. When mice were injected intraperitoneally with LPS, inducible nitric oxide synthase (iNOS) and arginase II were induced early in the lung and spleen. mRNAs for argininosuccinate synthase (AS) and ornithine decarboxylase (ODC) were also induced early. In comparison, arginase I was induced later in the lung. Early induction of iNOS, arginase II, AS, ODC, and cationic amino acid transporter 2 and late induction of arginase I were observed in LPS-activated peritoneal macrophages. These results indicate that the genes for the two arginase isoforms are regulated differentially. Possible roles of the arginase isoforms in the regulation of nitric oxide production and in polyamine synthesis are discussed.

Animals↗

PubMed2003

Dissection of experimental asthma with DNA microarray analysis identifies arginase in asthma pathogenesis.

Asthma is on the rise despite intense, ongoing research underscoring the need for new scientific inquiry. In an effort to provide unbiased insight into disease pathogenesis, we took an approach involving expression profiling of lung tissue from mice with experimental asthma. Employing asthma models induced by different allergens and protocols, we identified 6.5% of the tested genome whose expression was altered in an asthmatic lung. Notably, two phenotypically similar models of experimental asthma were shown to have distinct transcript profiles. Genes related to metabolism of basic amino acids, specifically the cationic amino acid transporter 2, arginase I, and arginase II, were particularly prominent among the asthma signature genes. In situ hybridization demonstrated marked staining of arginase I, predominantly in submucosal inflammatory lesions. Arginase activity was increased in allergen-challenged lungs, as demonstrated by increased enzyme activity, and increased levels of putrescine, a downstream product. Lung arginase activity and mRNA expression were strongly induced by IL-4 and IL-13, and were differentially dependent on signal transducer and activator of transcription 6. Analysis of patients with asthma supported the importance of this pathway in human disease. Based on the ability of arginase to regulate generation of NO, polyamines, and collagen, these results provide a basis for pharmacologically targeting arginine metabolism in allergic disorders.

Animals↗

PubMed2004

Mutation of amino acid 475 of rat organic cation transporter 2 (rOCT2) impairs organic cation transport.

Protein sequence alignments revealed one amino acid position, where organic cation transporters (OCTs, aspartate (D) at position 475 of rOCT2) and organic anion transporters (OATs, arginine (R) at position 466 of rOAT1) are charged oppositely. To address the impact of this amino acid for protein function we cloned rat organic cation transporter 2 (rOCT2), the renal electrogenic cation transporter of the basolateral side of proximal tubule cells. Site-directed mutagenesis was used to generate rOCT2-D475R (rOCT2-mut). Heterologous expression of rOCT2 wild-type (rOCT2-wt) in A6 cells resulted in a significant uptake of the fluorescent organic cation 4-(4-dimethylaminostyryl)-N-methylpyridinium (ASP(+)). Accordingly, rOCT2-wt-transfected COS 7 cells showed an almost fourfold uptake of 25 microM [(14)C]-TEA, whereas rOCT2-mut did not exhibit any uptake of [(14)C]-TEA. These data indicate that rOCT2 transports both ASP(+) and TEA and that aspartate at position 475 of rOCT2 plays a critical role in transport function.

Amino Acid Substitution↗

PubMed2004

Mechanisms underlying growth hormone effects in augmenting nitric oxide production and protein tyrosine nitration during endotoxin challenge.

The present study defined the effects of GH administration on components of the nitric oxide (NO)-generating cascade to account for observed increases in NO production and protein nitration after an immune challenge. Calves were assigned to groups with or without GH treatment (100 microg GH/kg body weight or placebo im, daily for 12 d) and with or without low-level endotoxin [lipopolysaccharide (LPS), 2.5 microg/kg, or placebo, iv]. Plasma was obtained for estimation of NO changes as [NO(2)(-) + NO(3)(-)] (NO(x)). Transcutaneous liver biopsies were collected for measurement of protein tyrosine nitration, cationic amino acid transporter (CAT)-2 mRNA transporter, and constitutive NO synthase (cNOS), inducible NOS (iNOS), and arginase activity. Liver protein nitration increased more than 10-fold 24 h after LPS and an additional 2-fold in animals treated with GH before LPS. GH increased plasma NO(x) after LPS to levels 27% greater than those measured in non-GH-treated calves. LPS increased CAT-2 mRNA after LPS; GH was associated with a 24% reduction in CAT-2 mRNA content at the peak time response. cNOS activity was 3-fold greater than iNOS after LPS. NOS activities were increased 140% (cNOS) at 3 h and 169% (iNOS) at 6 h, respectively, after LPS; GH treatment increased cNOS activity and the phosphorylation of endothelial NOS after LPS more than 2-fold over that measured in non-GH-treated calves. The data suggest that an increased production of nitrated protein develops in the liver during low-level, proinflammatory stress, and nitration is increased by GH administration through a direct effect on the competing activities of NOS and arginase, modulatable critical control points in the proinflammatory cascade.

Animals↗

PubMed2004

Augmented arginine uptake, through modulation of cationic amino acid transporter-1, increases GFR in diabetic rats.

BACKGROUND: It is suggested that either arginine or its metabolites, nitric oxide and polyamines play a role in the renal hemodynamic alterations observed in the early stages of diabetes. Yet, the regulation of arginine transport in diabetic kidneys has never been studied. METHODS: Arginine uptake was determined in glomeruli harvested from control rats; diabetic rats (2 weeks following an intraperitoneal injection of streptozotocin, 60 mg/kg body weight); rats, 4 days following left nephrectomy (a nondiabetic model of hyperfiltration); diabetes + lysine (0.5% in the drinking water to attenuate arginine uptake); and control + lysine. RESULTS: Glomerular arginine transport was significantly increased in diabetic rats, but remained unchanged following uninephrectomy. Lysine abolished the increase in arginine uptake in diabetic rats but had no effect in controls. The increase in creatinine clearance observed in diabetes was completely abolished by lysine. Using reverse transcription-polymerase chain reaction (RT-PCR), Northern blotting, and immunohistochemistry, we found a significant increase in glomerular cationic amino acid transporter-1 (CAT-1) expression in diabetic animals, which was unaffected by lysine. When human endothelial cells were incubated with arginine end products no effect on arginine transport was observed. However, only in the presence of 0.5 mM/L sodium nitroprusside (SNP) an augmented steady-state CAT-1 mRNA was demonstrated by RT-PCR. CONCLUSION: In a rat model of early diabetes, glomerular arginine uptake is elevated through modulation of CAT-1 expression, thus, contributing to the pathogenesis of hyperfiltration. Increased nitric oxide formation may play a role in this process.

Animals↗

PubMed2001

Lipopolysaccharide-induced apoptosis of macrophages determines the up-regulation of concentrative nucleoside transporters Cnt1 and Cnt2 through tumor necrosis factor-alpha-dependent and -independent mechanisms.

In murine bone marrow macrophages, lipopolysaccharide (LPS) induces apoptosis through the autocrine production of tumor necrosis factor-alpha (TNF-alpha), as demonstrated by the fact that macrophages from TNF-alpha receptor I knock-out mice did not undergo early apoptosis. In these conditions LPS up-regulated the two concentrative high affinity nucleoside transporters here shown to be expressed in murine bone marrow macrophages, concentrative nucleoside transporter (CNT) 1 and 2, in a rapid manner that is nevertheless consistent with the de novo synthesis of carrier proteins. This effect was not dependent on the presence of macrophage colony-stimulating factor, although LPS blocked the macrophage colony-stimulating factor-mediated up-regulation of the equilibrative nucleoside transport system es. TNF-alpha mimicked the regulatory response of nucleoside transporters triggered by LPS, but macrophages isolated from TNF-alpha receptor I knock-out mice similarly up-regulated nucleoside transport after LPS treatment. Although NO is produced by macrophages after LPS treatment, NO is not involved in these regulatory responses because LPS up-regulated CNT1 and CNT2 transport activity and expression in macrophages from inducible nitric oxide synthase and cationic amino acid transporter (CAT) 2 knock-out mice, both of which lack inducible nitric oxide synthesis. These data indicate that the early proapoptotic responses of macrophages, involving the up-regulation of CNT transporters, follow redundant regulatory pathways in which TNF-alpha-dependent- and -independent mechanisms are involved. These observations also support a role for CNT transporters in determining extracellular nucleoside availability and modulating macrophage apoptosis.

Animals↗

PubMed2002

Differential regulation of glomerular arginine transporters (CAT-1 and CAT-2) in lipopolysaccharide-treated rats.

The decrease in glomerular filtration rate (GFR) that is characteristic of sepsis has been shown to result from inhibition of glomerular endothelial nitric oxide synthase (eNOS) by nitric oxide (NO) generated from the inducible isoform of NOS (iNOS). Although l-arginine is the sole precursor for NO biosynthesis, its intracellular availability in glomeruli from septic animals has never been investigated. Arginine uptake was measured in freshly harvested glomeruli from the following experimental groups: 1) untreated rats; 2) rats pretreated with LPS (4 mg/kg body wt, 4 h before experiments); 3) rats treated with LPS as above with either l-N(6)-(1-iminoethyl)lysine hydrochloride (l-NIL), a selective iNOS antagonist, or 7-nitroindazole, a selective neuronal NOS antagonist; and 4) rats treated with l-NIL only. Both glomeular and mesangial arginine transport characteristics were found compatible with a y(+) system. Arginine uptake was augmented in glomeruli from LPS-treated rats. Treatment with l-NIL completely abolished this effect whereas l-NIL alone had no effect. Similar results were obtained when primary cultures of rat mesangial cells were preincubated with LPS (10 microg/ml for 24 h) with or without l-NIL. Using RT-PCR, we found that in vivo administration of LPS resulted in a significant increase in glomerular cationic amino acid transporter-2 (CAT-2) mRNA expression whereas CAT-1 mRNA was undetected. Northern blotting further confirmed a significant increase in glomerular CAT-2 by LPS. In mesangial cells, the expression of both CAT-1 and CAT-2 mRNA was augmented after incubation with LPS. In conclusion, in vivo administration of LPS augments glomerular arginine transport through upregulation of steady-state CAT-2 mRNA while downregulating CAT-1 mRNA. These results may correspond to the changes in glomerular iNOS and eNOS activity in sepsis.

Animals↗