RESUMO
Delayed sleep-wake phase disorder (DSWPD) is a subtype of circadian rhythm sleep-wake disorders, and is characterized by an inability to fall asleep until late at night and wake up at a socially acceptable time in the morning. The study aim was to identify low-frequency nonsense and missense variants that are associated with DSWPD. Candidate variants in circadian rhythm-related genes were extracted by integration of genetic variation databases and in silico assessment. We narrowed down the candidates to six variants. To examine whether the six variants are associated with DSWPD, we performed an association study in 236 Japanese patients with DSWPD and 1436 controls. A low-frequency missense variant (p.Val1205Met) in PER2 showed a significant association with DSWPD (2.5% in cases and 1.1% in controls, P = 0.026, odds ratio (OR) = 2.32). The variant was also associated with idiopathic hypersomnia known to have a tendency toward phase delay (P = 0.038, OR = 2.07). PER2 forms a heterodimer with CRY, and the heterodimer plays an important role in the regulation of circadian rhythms. Val1205 is located in the CRY-binding domain of PER2 and was hypothesized to interact with CRY. The p.Val1205Met substitution could be a potential genetic marker for DSWPD.
Assuntos
Povo Asiático/genética , Variação Genética/genética , Mutação de Sentido Incorreto/genética , Proteínas Circadianas Period/genética , Transtornos do Sono do Ritmo Circadiano/genética , Alelos , Estudos de Casos e Controles , Frequência do Gene/genética , HumanosRESUMO
The rehabilitation program has been conducted at our psychiatric clinic for depressive patients who are absent from work, with the aim of assisting them to return to work. We have noticed that a substantial number of the patients have traits of developmental disorders, which contribute to chronicity and/or recurrence of depression. Therefore, we have recently created a new rehabilitation program in addition to the specialty outpatient clinic and peer support group. All these programs specialize in treating adult patients with mild developmental disorders [mostly autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD)]. Since then, we have investigated a lot of depressive patients whose ASD symptoms have been identified for the first time in their life. Symptoms were first noted after they started work where they experienced impaired social functioning because the social demands were higher than those at schools. To assist patients with their goals of improving symptoms and stabilizing social functions, it is valid to evaluate whether the autistic traits cause mental stress and impairment during occupational functioning, even if the diagnosis of ASD is not definitive or the symptoms are below the diagnostic threshold for ASD. The profile of ASD symptoms is different for each patient, and therefore personalized support is essential.
Assuntos
Instituições de Assistência Ambulatorial , Transtorno do Deficit de Atenção com Hiperatividade/reabilitação , Transtorno Autístico/reabilitação , Depressão/reabilitação , Deficiências do Desenvolvimento/reabilitação , Adulto , Humanos , Ajustamento SocialRESUMO
Genetic studies have revealed several clock gene variations/mutations involved in the manifestation of sleep disorders or interindividual differences in sleep-wake patterns, but only part of the genetic risk can be explained by the gene variations/mutations identified to date. Recent progress in research into circadian rhythm generation has provided efficient tools for eliciting the molecular basis of clock-relevant sleep disorders, complementing traditional genetic analysis. While the human master clock resides in the suprachiasmatic nucleus of the hypothalamus (central clock), peripheral tissue cells also generate self-sustained circadian oscillations of clock gene expression (peripheral clock), enabling estimation of individual human clock properties through a single collection of skin fibroblasts or venous blood cells. Some of the established cell lines exhibit autonomous circadian oscillations of clock gene expression, and introduction of clock gene variations into these cell lines by gene targeting makes it possible to investigate changes in the circadian phenotype induced by these variations/mutations without the need for generating transgenic animals. Estimation of human clock properties using peripheral tissue cells, in addition to genetic analysis, will facilitate comprehensive explication of the genetic risk of a variety of disorders relevant to biological clock disturbances, including sleep disorders, mood disorders, and metabolic diseases.
Assuntos
Relógios Biológicos/genética , Regulação da Expressão Gênica , Modelos Genéticos , Transtornos do Sono do Ritmo Circadiano/genética , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Animais , Relógios Biológicos/fisiologia , Proteínas CLOCK/genética , Proteínas CLOCK/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Células Cultivadas , Criptocromos/genética , Criptocromos/metabolismo , Humanos , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Transtornos do Sono do Ritmo Circadiano/fisiopatologia , Transcrição GênicaRESUMO
Panic disorder (PD) is a severe and chronic psychiatric disorder, with genetic components underlying in its etiology. The PERIOD2 (Per2) gene has been reported to be associated with familial advanced sleep phase syndrome. Considering the high frequency of sleep disturbance in PD, Per2 may be a candidate gene for PD. Therefore, we conducted a two-stage case-control association study in the Japanese population. In the first screening sample of 203 patients and 409 controls, we investigated three single-nucleotide polymorphisms in Per2. We found a potential association in the screening sample (rs2304672, genotype P=0.046, uncorrected), whereas we could not replicate the association in the second sample of 460 patients and 460 controls. Our results suggest that Per2 may not have a major role in the pathogenesis of PD in the Japanese population.
Assuntos
Povo Asiático/genética , Predisposição Genética para Doença , Transtorno de Pânico/genética , Proteínas Circadianas Period/genética , Adulto , Estudos de Casos e Controles , Feminino , Frequência do Gene , Estudo de Associação Genômica Ampla , Genótipo , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Adulto JovemRESUMO
OBJECTIVE: To describe surgical repair of a large atrial septal defect (ASD) in a cat. STUDY DESIGN: Clinical report. ANIMAL: A 3-year-old, 3.3 kg, intact male Japanese domestic short-haired cat. METHODS: A 10.2-mm-diameter ASD detected by echocardiography was surgically corrected because pulmonary vascular resistance-to-systemic vascular resistance ratio (Qp /Qs ) was 3.2. Using cardiopulmonary bypass (CPB), open surgical repair was achieved with an expanded polytetrafluoroethylene (e-PTFE) graft. The priming volume of the CPB circuit was minimized by cutting the CPB tubing, and partially replacing the priming fluid with whole cat blood. To prevent hemodilution associated with use of cardioprotective agents, surgery was performed on the beating heart. RESULTS: At 1-year echocardiographic evaluation, the repair was intact, and at 3 years, the cat was alive without need of medication. CONCLUSIONS: Large ASD in a cat can be repaired using e-PTFE under CPB.
Assuntos
Ponte Cardiopulmonar/veterinária , Doenças do Gato/cirurgia , Comunicação Interatrial/veterinária , Animais , Gatos , Comunicação Interatrial/cirurgia , MasculinoRESUMO
OBJECTIVE: To describe surgical repair of a complete endocardial cushion defect (ECD) in a dog. STUDY DESIGN: Clinical report. ANIMAL: A 5-month-old, 9.2 kg male Shetland sheepdog. METHODS: Echocardiographic examination revealed an ostium primum atrial septal defect (ASD), an inlet ventricular septal defect (VSD), mitral regurgitation (MR) and tricuspid regurgitation (TR), and a complete ECD was diagnosed. Surgical correction was performed using cardiopulmonary bypass (CPB) via right atriotomy. A polytetrafluoroethylene (PTFE) patch was secured along the margin of the inlet VSD using simple continuous suture, then the cleft in the septal mitral leaflet was sutured. Similarly, the cleft in the septal tricuspid leaflets was sutured. To complete inlet VSD closure, the VSD patch was secured to these sutured leaflets by simple continuous suture. Another PTFE patch was used to close the ostium primum ASD. RESULT: After surgery, MR, TR, and interventricular shunting were decreased. The dog was alive 6 years and 5 months after the surgery with no evidence of an interventricular shunt, TR, or other clinical signs. CONCLUSIONS: Complete ECD in a dog was corrected using a 2-patch technique under CPB.
Assuntos
Doenças do Cão/cirurgia , Comunicação Atrioventricular/veterinária , Insuficiência da Valva Mitral/veterinária , Insuficiência da Valva Tricúspide/veterinária , Animais , Cães , Comunicação Atrioventricular/cirurgia , Comunicação Interatrial/cirurgia , Comunicação Interatrial/veterinária , Comunicação Interventricular/cirurgia , Comunicação Interventricular/veterinária , Masculino , Insuficiência da Valva Mitral/cirurgia , Insuficiência da Valva Tricúspide/cirurgiaRESUMO
We aim to develop a cultured cell model, to serve as a system with which the altered circadian phenotypes produced by the clock gene variations could be studied in vitro. Tau mutation, which shortens the circadian period of hamsters and mice, was introduced into the CK1epsilon locus of cultured Rat1-R12 cells by gene targeting mediated by a recombinant adeno-associated virus (rAAV) vector. After transduction of Rat1-R12 cells with rAAV, about 0.14% of the drug-resistant cells underwent gene targeting at CK1epsilon locus. Of the three clones isolated, only one carried the targeted allele of tau mutation and two carried the targeted wild-type allele. The clone with the targeted tau mutant allele exhibited a significantly shorter circadian period compared to the clone with targeted wild-type allele. rAAV-mediated gene targeting in cultured somatic cells is a convenient and powerful tool for analyzing the phenotypic outcome of clock gene variations, and for elucidating the pathogenesis of the disorders associated with abnormal circadian rhythmicity.
Assuntos
DNA Recombinante/genética , Dependovirus/genética , Marcação de Genes , Vetores Genéticos/genética , Mutação/genética , Alelos , Animais , Southern Blotting , Proliferação de Células , Células Cultivadas , Ritmo Circadiano/genética , Células Clonais , RatosRESUMO
We have established human retinal pigment epithelial cell lines stably expressing the luciferase gene, driven by the human Bmal1 promoter, to obtain human-derived cells that show circadian rhythms of bioluminescence after dexamethasone treatment. The average circadian period of bioluminescence for the obtained clones was 24.07+/-0.48 h. Lithium (10 mM) in the medium significantly lengthened the circadian period of bioluminescence, which is consistent with previous reports, while 2 mM or 5 mM lithium had no effect. This is the first report on the establishment of human-derived cell lines that proliferate infinitely and show circadian rhythms of bioluminescence, and also the first to investigate the effects of low-dose lithium on the circadian rhythms of human-derived cells in vitro. The established cells will be useful for various in vitro studies of human circadian rhythms and for the development of new therapies for human disorders related to circadian rhythm disturbances.
Assuntos
Ritmo Circadiano/fisiologia , Células Epiteliais/metabolismo , Luciferases/metabolismo , Medições Luminescentes/métodos , Fatores de Transcrição ARNTL , Antimaníacos/farmacologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Linhagem Celular , Dexametasona/farmacologia , Relação Dose-Resposta a Droga , Células Epiteliais/citologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Humanos , Cloreto de Lítio/farmacologia , Luciferases/genética , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas/genética , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/metabolismoRESUMO
OBJECTIVE: To clarify regulation of the renin-angiotensin (RA) system in cardiac tissues by measuring angiotensin-converting enzyme (ACE) and chymase activities in cats with pressure-overload cardiac hypertrophy. ANIMALS: 13 adult cats. PROCEDURES: Pressure-overload cardiac hypertrophy was induced by coarctation of the base of the ascending aorta in 6 cats, and 7 cats served as untreated control animals. Cats were examined before and 3 months and 2 years after surgery. Two years after surgery, cardiac hypertrophy was confirmed by echocardiography, and the blood pressure gradient was measured at the site of constriction. Cats were euthanized, and ACE and chymase activities were measured in cardiac tissues. RESULTS: Mean +/- SD pressure gradient across the aortic constriction was 63 +/- 6 mm Hg. Chymase activity predominated (75% to 85%) in the RA system of the cardiac tissues of cats. Fibrosis in the wall of the left ventricle was detected in cats with hypertrophy, and fibrosis of the papillary muscle was particularly evident. CONCLUSIONS AND CLINICAL RELEVANCE: Chronic pressure overload on the heart of cats can activate the RA system in cardiac tissues. A local increase in angiotensin II was one of the factors that sustained myocardial remodeling.
Assuntos
Doenças do Gato/fisiopatologia , Hipertrofia Ventricular Esquerda/veterinária , Sistema Renina-Angiotensina/fisiologia , Animais , Pressão Sanguínea/fisiologia , Doenças do Gato/enzimologia , Doenças do Gato/patologia , Gatos , Quimases/metabolismo , Ecocardiografia/veterinária , Histocitoquímica/veterinária , Hipertrofia Ventricular Esquerda/enzimologia , Hipertrofia Ventricular Esquerda/patologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Peptidil Dipeptidase A/metabolismoRESUMO
We examined the influence of sex steroids on cardiac effects of sympathetic agents in mice. The mice were divided into four groups: males, neutered males (N-males), females, and neutered females (N-females). Dobutamine (DOB; 2.5, 5.0, 10 microg/kg/min) or isoproterenol (ISO; 0.01, 0.02, 0.04 microg/kg/min) were given intravenously to compare the fractional shortening (FS). These mice received isoproterenol twice daily at a dose of 7.5 microg/g/day for 3 weeks. The rate of cardiac fibrosis was evaluated pathologically with Azan stain after 3 weeks of ISO. DOB and ISO significantly increased the FS in the male group, compared with other groups. There was no significant difference in FS between the female and N-female groups. Cardiac fibrosis significantly increased in the male group, compared with the N-male group. The female and N-female groups had increased cardiac fibrosis, compared with the male and N-male groups. These findings suggest that testosterone is one of the factors of modulation of the response to the sympathetic nervous system. Further study is needed to clarify the relationships between female sex steroids and cardiac fibrosis.
Assuntos
Miocárdio/patologia , Caracteres Sexuais , Sistema Nervoso Simpático/fisiologia , Animais , Dobutamina/farmacologia , Relação Dose-Resposta a Droga , Feminino , Fibrose , Coração/fisiopatologia , Isoproterenol/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos , Orquiectomia , Ovariectomia , Sistema Nervoso Simpático/efeitos dos fármacos , Simpatomiméticos/farmacologia , Testosterona/fisiologiaRESUMO
Circadian rhythm sleep-wake disorders (CRSWDs) are characterized by disturbed sleep-wake patterns. We genotyped a PER3 variable number tandem repeat (VNTR) in 248 CRSWD individuals and 925 controls and found no significant association between the VNTR and CRSWDs or morningness-eveningness (diurnal) preferences in the Japanese population. Although the VNTR has been associated with circadian and sleep phenotypes in some other populations, the polymorphism may not be a universal genetic marker.
Assuntos
Proteínas CLOCK , Receptores Citoplasmáticos e Nucleares , Proteínas Repressoras , Transtornos do Sono do Ritmo Circadiano , Humanos , Ritmo Circadiano , População do Leste Asiático , Melatonina , Receptores Citoplasmáticos e Nucleares/genética , Proteínas Repressoras/genética , Sono , Transtornos do Sono do Ritmo Circadiano/genética , Proteínas CLOCK/genéticaRESUMO
OBJECTIVE: To investigate the relationship between myocardial performance index (MPI; also known as the Tei index) and cardiac function in anesthetized cats administered dobutamine. ANIMALS: 6 adult cats. PROCEDURES: Cats were anesthetized by administration of propofol (6 mg/kg, IV), and anesthesia was maintained by administration of isoflurane. Heart rate and systolic arterial pressure (SAP) were monitored. Stroke volume, cardiac output, and aortic blood flow (ABF) were measured by use of transesophageal ultrasonography. Left ventricular fractional shortening (LVFS), mitral E-wave velocity-to-A-wave velocity (E:A) ratio, and ejection time were measured by use of transthoracic echocardiography. Dobutamine was administrated via a cephalic vein at rates of 2.5, 5.0, and 10 microg/kg/min. RESULTS: Heart rate, SAP, cardiac output, and ABF increased with dobutamine administration, whereas stroke volume significantly decreased. The LVFS significantly increased, and the E:A ratio significantly decreased. Total isovolumic time and the MPI significantly decreased. The MPI was negatively correlated (r=-0.63) with LVFS. Conversely, the MPI was positively correlated with the E:A ratio (r=0.47), stroke volume (r=0.66), and total isovolumic time (r=0.95). However, the MPI was not significantly correlated with heart rate, SAP, cardiac output, or ABF. CONCLUSION AND CLINICAL RELEVANCE: Analysis suggested that the MPI provides a sensitive clinical assessment of cardiac response to medication in cats, which may be similar to the usefulness of the MPI reported in humans.
Assuntos
Gatos/fisiologia , Dobutamina/farmacologia , Coração/efeitos dos fármacos , Análise de Variância , Anestesia/veterinária , Animais , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Relação Dose-Resposta a Droga , Frequência Cardíaca/efeitos dos fármacos , Volume Sistólico/efeitos dos fármacosRESUMO
Polymorphisms in clock genes induce circadian rhythm sleep disorders. Mutations in Per2 gene (S662G) or Casein Kinasel delta (CK16) gene (T44A) cause Familial advanced sleep phase syndrome. Missense polymorphisms in Per3 (V647G) and CK1e (S408N) genes increase or decrease the risk of developing delayed sleep phase syndrome. All of these polymorphisms seem to affect the phosphorylation of the clock proteins. Some of the polymorphisms in CK1, which shows reduced enzyme activity in vitro, induced increased phosphorylation of PER proteins in in vivo assays. Careful attention should be paid to analyze the complex system composed of feedback loops, such as the biological clock.
Assuntos
Relógios Biológicos/genética , Caseína Quinase Idelta/genética , Proteínas Nucleares/genética , Polimorfismo Genético/genética , Transtornos do Sono do Ritmo Circadiano/genética , Fatores de Transcrição/genética , Animais , Caseína Quinase 1 épsilon/genética , Humanos , Mutação de Sentido Incorreto , Proteínas Circadianas Period , FosforilaçãoRESUMO
Vertebrate eyes are known to contain circadian clocks, however, the intracellular mechanisms regulating the retinal clockwork remain largely unknown. To address this, we generated a cell line (hRPE-YC) from human retinal pigmental epithelium, which stably co-expressed reporters for molecular clock oscillations (Bmal1-luciferase) and intracellular Ca2+ concentrations (YC3.6). The hRPE-YC cells demonstrated circadian rhythms in Bmal1 transcription. Also, these cells represented circadian rhythms in Ca2+-spiking frequencies, which were canceled by dominant-negative Bmal1 transfections. The muscarinic agonist carbachol, but not photic stimulation, phase-shifted Bmal1 transcriptional rhythms with a type-1 phase response curve. This is consistent with significant M3 muscarinic receptor expression and little photo-sensor (Cry2 and Opn4) expression in these cells. Moreover, forskolin phase-shifted Bmal1 transcriptional rhythm with a type-0 phase response curve, in accordance with long-lasting CREB phosphorylation levels after forskolin exposure. Interestingly, the hRPE-YC cells demonstrated apparent circadian rhythms in phagocytic activities, which were abolished by carbachol or dominant-negative Bmal1 transfection. Because phagocytosis in RPE cells determines photoreceptor disc shedding, molecular clock oscillations and cytosolic Ca2+ signaling may be the driving forces for disc-shedding rhythms known in various vertebrates. In conclusion, the present study provides a cellular model to understand molecular and intracellular signaling mechanisms underlying human retinal circadian clocks.
Assuntos
Relógios Biológicos/fisiologia , Sinalização do Cálcio/fisiologia , Regulação da Expressão Gênica/fisiologia , Fagocitose/fisiologia , Receptor Muscarínico M3/biossíntese , Epitélio Pigmentado da Retina/metabolismo , Cálcio/metabolismo , Linhagem Celular Transformada , Humanos , Epitélio Pigmentado da Retina/citologiaRESUMO
The precise mechanism of the progression of advanced heart failure is unknown. We assessed a new scheme in two heart failure models: (I) congenital dilated cardiomyopathy (DCM) in TO-2 strain hamsters lacking delta-sarcoglycan (SG) gene and (II) administration of a high-dose of isoproterenol, as an acute heart failure in normal rats. In TO-2 hamsters, we followed the time course of the histological, physiological and metabolic the progressions of heart failure to the end stage. Dystrophin localization detected by immunostaining age-dependently to the myoplasm and the in situ sarcolemma fragility evaluated by Evans blue entry was increased in the same cardiomyocytes. Western blotting revealed a limited cleavage of the dystrophin protein at the rod domain, strongly suggesting a contribution of endogenous protease(s). We found a remarkable up-regulation of the amount of calpain-1 and -2, and no change of their counterpart, calpastatin. After supplementing TO-2 hearts with the normal delta-SG gene in vivo, these pathological alterations and the animals' survival improved. Furthermore, dystrophin but not delta-SG was disrupted by a high dose of isoproterenol, translocated from the sarcolemma to the myoplasm and fragmented. These results of heart failure, irrespective of the hereditary or acquired origin, indicate a vicious cycle formed by the increased sarcolemma permeability, preferential activation of calpain over calpastatin, and translocation and cleavage of dystrophin would commonly lead to advanced heart failure.
Assuntos
Cardiomiopatia Dilatada/fisiopatologia , Distrofina/fisiologia , Animais , Proteínas de Ligação ao Cálcio/biossíntese , Calpaína/metabolismo , Cardiomiopatia Dilatada/congênito , Cardiomiopatia Dilatada/terapia , Permeabilidade da Membrana Celular , Cricetinae , Dependovirus/fisiologia , Modelos Animais de Doenças , Ativação Enzimática , Terapia Genética , Insuficiência Cardíaca/induzido quimicamente , Isoproterenol , Mesocricetus , Modelos Biológicos , Ratos , Sarcoglicanas/deficiência , Sarcoglicanas/genética , Sarcolema/fisiologiaRESUMO
The ciliary neurotrophic factor (CNTF) is a neurotrophic cytokine that plays a critical role in neurodevelopment. On the basis of neurodevelopmental hypothesis, the CNTF gene has been a candidate locus for schizophrenia. Several studies have investigated the association between the null mutation of the gene and schizophrenia, however, with inconsistent results. In the present study, we investigated the association in 222 Japanese patients with schizophrenia and 237 controls. The association between the mutation and personality traits was also studied, to investigate the effect of the mutation in participants from the general population. As a result, no association was observed between the mutation and schizophrenia nor personality traits, evaluated by using the Revised NEO Personality Inventory scores. The present study did not provide evidence for the association between the CNTF gene and schizophrenia or personality traits in the Japanese population.
Assuntos
Fator Neurotrófico Ciliar/genética , Mutação , Personalidade/genética , Esquizofrenia/genética , Alelos , Frequência do Gene , Genótipo , HumanosRESUMO
Serotonin 2C receptor (5-HT(2C)), serotonin 6 receptor (5-HT(6)), and tryptophan hydroxylase-1 (TPH1) genes could be candidates for personality-related genes considering the role of serotonin in various mental functions and behavior. However, a limited number of studies have investigated the association between these genes and personality traits. In the present study, we investigated the three serotonin-related genes, 5-HT(2C), 5-HT(6), and TPH1 genes, in relation to personality traits in the Japanese population. The Cys23Ser polymorphisms in the 5-HT(2C) gene, the 267T/C polymorphism of the 5-HT(6) gene, and the 779A/C polymorphisms in the TPH1 gene were genotyped in 253 healthy Japanese subjects. Personality traits were evaluated by using the Revised NEO Personality Inventory (NEO PI-R) and the State-Trait Anxiety Inventory (STAI). As a result, no significant association was observed between the polymorphisms and the NEO PI-R or the STAI scores. The present results did not provide evidence for the association between the three serotonin-related genes and personality traits. The genes might not have major role in the development of personality traits, although further investigation with larger sample size may be recommended for conclusion.
Assuntos
Personalidade/genética , Receptor 5-HT2C de Serotonina/genética , Receptores de Serotonina/genética , Triptofano Hidroxilase/genética , Adulto , Povo Asiático , Feminino , Humanos , Japão , Masculino , Polimorfismo GenéticoRESUMO
The aim of the present study was to evaluate short term urinary NAG levels in a model of reduced kidney mass. The half and quarter kidney mass were made from ligation of the renal artery. Both groups decreased in the level of excreted NAG on day 1 and 2 after operation. On day 5 after operation, both groups achieved urinary enzyme levels comparable to that of the sham-operated group. The remaining compensated nephrons held normal range of excreted urinary NAG levels, although reduced number of nephrons resulted in a decline in urinary NAG levels.