Guanine aminohydrolase (GAH), one of purine metabolizing enzymes rich in the nervous system was proved to have identical amino acid sequence to a recently identified novel protein p51-nedasin, NE-dlg/SAP102-associated protein. Nedasin has been reported to localize at neuronal cell bodies and binds to SAP102, so it might have a role in modulating NMDA receptor 2B clustering of SAP102 or synaptic organization in neuronal cells. In this study, we localize GAH and SAP102 in rat retina using immunohistochemical method. Immunoreactivities are detected for both GAH and SAP102 in ganglion cell layer, inner plexiform layer, inner nuclear layer, outer plexiform layer and pigment layer. They seemed to be colocalized in ganglion cells, amacrine cells, horizontal cells and pigment cells. The staining profile for SAP102 is almost identical with NMDA receptor 2B mainly in fibrous elements in both the inner and outer plexiform layer. Our results support the possibility of close structural relationship between GAH and SAP102 in specific retinal cells and GAH involvement in synaptic organization association with SAP102 in the rat retina.
Amacrine Cells ; Amino Acid Sequence ; Animals ; Ganglion Cysts ; Guanine Deaminase* ; Guanine* ; N-Methylaspartate ; Nervous System ; Neurons ; Rats* ; Retina* ; Retinaldehyde

Guanine aminohydrolase (GAH; Guanine deaminase, EC 3.5.4.3) is an enzyme that has a role in purine catabolism. Most of the enzymes involved in purine catabolism have been studied for their biological functions, physiological roles and amino acid sequences, and biochemical activity of GAH is known to be detected in various organs such as liver, kidney, small intestine and brain. Its activity is also known to be changed during development of the nervous system. Although there have been studies on GAH, the histological distribution of GAH in the rat retina has not been examined until now. In this study, in order to investigate the cellular distribution and temporal regulation of GAH in rat retina, we performed immunohistochemistry in retinal sections at different developmental ages between postnatal day 0 (P0, birthdate) and the adult stage using specific antibody against GAH. GAH immunoreactivity was observed in the ganglion cell layer and inner plexiform layer at P0. From P5, GAH staining appeared in the inner part of the neuroblast layer, where amacrine cells localize. At P14, labeling of GAH also was observed in horizontal cell bodies and in the outer plexiform layer. Immunoreactivity of GAH in horizontal cell bodies was increased and strong punctate reactivity was observed in the outer plexiform layer at the adult rat retina, whereas the number and intensity of immunoreactive amacrine cell bodies in the inner part of inner nuclear layer decreased. From these results, we can suggest that GAH may be involved in the establishment of synaptic connections and signal transduction in the developing rat retina.
Adult ; Amacrine Cells ; Amino Acid Sequence ; Animals ; Brain ; Ganglion Cysts ; Guanine Deaminase* ; Guanine* ; Humans ; Immunohistochemistry ; Intestine, Small ; Kidney ; Liver ; Metabolism ; Nervous System ; Rats* ; Retina* ; Retinaldehyde ; Signal Transduction

PURPOSE: The pathophysiological mechanisms of the bladder dysfunction in postmenopausal state are not well understood especially in moleclular level. Therefore we investigated the changes of bladder in female rat following bilateral ovariectomy by proteomic approach. MATERIALS AND METHODS: A total 10 female Sprague-Dawley rats were obtained at 8 weeks of age and randomly divided into 2 groups in each 5 rats; sham operation group as the control group and the bilateral ovariectomy group. Whole urinary bladders of the rats were excised 4 weeks after the beginning of the experiment. Conventional proteomics was performed with high resolution 2-D gel electrophoresis followed by computational image analysis and protein identification using mass spectrometry. RESULTS: Bladder weight was not changed by oophorectomy. A comparison of bladder of ovariectomy group with control showed that 8 proteins; Eukaryotic translation initiation factor 5A was over-expressed, and chaperone grp 75 precursor, guanine deaminase, keratin complex 2, Gelsolin precursor, peroxiredoxin 2, Enol protein and contrapsin-like inhibitor 1 precursor were under-expressed in the oophorectomy group. CONCLUSION: These data suggested that the bilateral oophorectomy might make a bladder to have a cellular apoptosis and a change of contractility in the rat bladder. However more information is needed in human bladder tissue for clinical usage and long-term proteomic changes are needed.
Animals ; Apoptosis ; Electrophoresis, Gel, Two-Dimensional ; Female ; Female* ; Gelsolin ; Guanine Deaminase ; Humans ; Mass Spectrometry ; Ovariectomy* ; Peptide Initiation Factors ; Peroxiredoxins ; Proteomics ; Rats* ; Rats, Sprague-Dawley ; Urinary Bladder*

Guanine aminohydrolase(GAH;EC 3. 5. 4. 3.) was partially purified 122-fold from rat cerebrum to a specific activity of 7.22 in its per mg protein with a recovery of 7.47% by fractionation with ammonium sulfate, chromatography on DEAE-cellulose and hydroxyapatite, gel filtration on Sephadex G-200, and isoelectric focusing(pH4-6). The molecular weight of partially purified rat cerebral guanine aminohydrolase was estimated to be 110,000. But, in the cerebral cytosol, a rather higher molecular weight form of the enzyme was identified. The activity of the higher molecular weight form of guanine aminohydrolase was increased by dialyzing the cytosol, and it was converted into the lower molecular weight form(M.W.110,000) by addition of 2-mercaptoethanol. The reaction velocity of partially purified guanine aminohydrolase of rat cerebrum disclosed a hyperbolic curve, with its KM being 6.0uM at pH 8.0. The preparation showed high substrate specificity:among the purine nucleotides, nucleosides and bases with amino group, only guanosine and guanine were deaminated by the enzyme, and the reaction rate of the enzyme displayed by guanosine was less than 10% of that by guanine. When observed under the equimolar concentration of the substrate, hypoxanthine as well as inosine inhibited the activity of the rat cerebral guanine aminohydrolase by 9.4 and 7.8%, respectively, while 5-aminoimidazole-4-carboxamide inhibited the activity of it by 38%. The activity was inhibited by p-hydroxymercuric benzoate as well. Complete loss of its activity was observed after 30 minutes incubation at 60 degrees C, suggesting the preparation was heat labile.
Ammonium Sulfate ; Animals ; Benzoates ; Cerebrum* ; Chromatography ; Chromatography, Gel ; Cytosol ; DEAE-Cellulose ; Durapatite ; Filtration ; Guanine Deaminase* ; Guanine* ; Guanosine ; Hot Temperature ; Hydrogen-Ion Concentration ; Hypoxanthine ; Inosine ; Mercaptoethanol ; Molecular Weight ; Nucleosides ; Purine Nucleotides ; Rats* ; Xanthine Oxidase

PURPOSE: To explore the effect of bilateral oophorectomy on the several proteins of female rat bladder via a proteomic approach. MATERIALS AND METHODS: A total of 20 female Sprague-Dawley rats were obtained at 8 weeks of age and were divided randomly into 3 groups: a control groups underwent sham operation and bladders were excised 4 weeks and 8 weeks after operation each. Other two groups underwent bilateral oophorectomy and bladders were excised 4 weeks (group 1) and 8 weeks (group 2) after operation each, too. Each group has 5 rats. Conventional proteomics was conducted via high resolution 2-D gel electrophoresis, followed by image analysis and protein identification through mass spectrometry. RESULTS: Bladder weights were reduced significantly in group 2 as compared with the 8-week control group. A comparison of the bladders of the oophorectomy group subjects with those of the control group subjects demonstrated that the expressions of 11 proteins were altered Eukaryotic translation initiation factor 5A (elF-5A), chaperone grp 75 precursor, actin-depolymerizing factor, contrapsin-like inhibitor 1 precursor, guanine deaminase, actin, peroxiredoxin 2, phosphatidylethanolamine, putative protein kinase, Keratin complex 2 and Enol protein. CONCLUSION: The roles of 11 proteins are variable. A part of these proteins have a role of cellular apoptosis, acute inflammation, and muscle contraction. It seems that these changes of proteins have an influence on bladder functions and LUTS.
Actins ; Animals ; Apoptosis ; Electrophoresis, Gel, Two-Dimensional ; Female ; Guanine Deaminase ; Humans ; Inflammation ; Mass Spectrometry ; Muscle Contraction ; Ovariectomy* ; Peptide Initiation Factors ; Peroxiredoxins ; Protein Kinases ; Proteomics ; Rats* ; Rats, Sprague-Dawley ; Urinary Bladder* ; Weights and Measures

Guanine aminohydrolase (GAH; Guanine deaminase, EC 3.5.4.3) is an enzyme that has a role in purine catabolism. This enzyme produces xanthine and ammonia by hydrolysis of guanine, and xanthine is further degraded to uric acid and hydrogen peroxide by another enzyme, xanthine oxidase. Most of the enzymes involved in purine catabolism have been studied for their biological functions, physiological roles and amino acid sequences, and biochemical activity of GAH is known to be detected in various organs such as liver, kidney, small intestine and brain. Its activity is also known to be changed during brain development. In this study, we hoped to reveal expression pattern of GAH in developing rat brain by western blotting and immunohistochemistry. In western blotting, GAH immunoreactivity was not detected on 14-, 16- and 18-days-old fetal rat brains. Its reactivity was first detected from 20-days-old fetal rat brain and highly increased after birth. And it was maintained at steady level from 2 weeks after birth. In immunohistochemistry, no positive cells were found on 14- and 16-days-old fetal rat brain sections. A few GAH-immunoreactive cells appeared from 18-days-old fetal rat brain and they were localized at olfactory bulb, cerebral cortex, midbrain, pons and medulla. The 20-days-old fetal rat brain also showed immunoreactive cells at hippocampus and the staining intensity was still weak. Postnatal 2-days-old rat brain also showed immunoreactive cells at basal ganglia and the number of positive cells and staining intensity were increased. Thereafter, immunoreactivity appeared on many neuronal cells around various areas in the brain and nerve fibers also showed reactivity on postnatal brains. The number of positive cells decreased from 1 week after birth and a few positive cells were observed on olfactory bulb and cerebellum from 2 weeks after birth. In mature brain most of GAH were localized on nerve fibers and few positive cells could be found on olfatory bulb only. From these, we can suspect that GAH may have some functional relationship with nerve fibers.
Amino Acid Sequence ; Ammonia ; Animals ; Basal Ganglia ; Blotting, Western ; Brain* ; Cerebellum ; Cerebral Cortex ; Guanine Deaminase* ; Guanine* ; Hippocampus ; Hope ; Hydrogen Peroxide ; Hydrolysis ; Immunohistochemistry ; Intestine, Small ; Kidney ; Liver ; Mesencephalon ; Metabolism ; Nerve Fibers ; Neurons ; Olfactory Bulb ; Parturition ; Pons ; Rats* ; Uric Acid ; Xanthine ; Xanthine Oxidase