Spasmolytic Effect of Flopropione Does Not Involve Catechol-O- methyltransferase (COMT) Inhibition.

Flopropione (Flo) has been used for gallstone and urolithiasis as a spasmolytic agent almost exclusively in Japan. According to the package insert, its main mechanism is catechol-O-methyltransferase (COMT) inhibition and anti-serotonergic effect. This is obviously contrary to pharmacological common sense, but it is described that way in pharmacology textbooks and occurs in questions in the National Examination for Pharmacists in Japan. As this is a serious problem in education, we re-examined the action of Flo. The guinea pig ureter was hardly contracted by serotonin, but noradrenaline (NA) elicited repetitive twitch contraction, which was inhibited by Flo. The sphincter of Oddi (SO) exhibited a spontaneous repetitive twitch contraction, which was inhibited by NA and Flo. The inhibitory effect of NA was reversed by α- and ß-blockers, whereas that of Flo was not. Entacapone, a representative COMT inhibitor, did not affect the movement of the ureter and the SO. Nifedipine suppressed carbachol-induced contraction of the taenia coli, spontaneous movement of the SO, and NA-induced contraction of the ureter to almost the same extent, whereas Flo did not inhibit the taenia coli, but inhibited the contraction of the SO and the ureter. The inhibitory pattern of Flo resembled that of the ryanodine receptor agonist 4-chloro-m-cresol and the inositol 1,4,5-trisphosphate (IP3) receptor antagonist 2-aminoethoxydiphenyl borate. It is concluded that COMT inhibition or serotonin inhibition is not involved in the spasmolytic action of Flo. Flo might act on ryanodine receptors and/or IP3 receptors, which are responsible for periodic Ca release from Ca stores, to disrupt coordinated Ca dynamics.

Effect of Helicobacter pylori eradication on elder cases: Observational study in community-based medicine.

AIM: To examine the effect of Helicobacter pylori (H. pylori) eradication therapy on the extra-gastrointestinal factors in elderly patients by a before-after observational study in community medicine. METHODS: Medical records (1 May 2013-31 January 2014) of 130 patients who underwent H. pylori eradication therapy with 2-year after-eradication observation in our institute were reviewed. Data on sex; age; body weight; body mass index (BMI); mean corpuscular volume (MCV); total protein; low-density lipoprotein cholesterol, triglyceride, haemoglobin A1c and haemoglobin levels and gastric hyperplastic polyps (GHPs) at eradication was extracted. Two-year after-eradication change in data was analysed by paired-sample t-test; relationship between GHPs and subclinical iron deficiency anaemia (IDA) improvement was evaluated. RESULTS: The mean patient age (median, interquartile range) at eradication was 69.6 (71.5, 64-77) years. Paired-sample t-tests showed that body weight, BMI and MCV increased by 0.52 kg (P = 0.018), 0.25 kg/m2 (P = 0.006) and 0.83 fL (P < 0.001), respectively. The nonparametric Mann-Whitney test showed no significant difference in the change rate of MCV after eradication between the groups with and without GHPs (P = 0.892). CONCLUSION: H. pylori eradication therapy prevented weight loss and subclinical IDA in elderly individuals. GHPs were not associated with subclinical IDA.

Diagnosis and management of giant hepatic hemangioma: the usefulness of contrast-enhanced ultrasonography.

Giant hepatic hemangiomas, though often asymptomatic, may require intervention if rapid growth occurs. The imaging studies including the computed tomography, magnetic resonance imaging, and ultrasonography, and so on are effective for the diagnosis and the management of this tumor; however, due to its size and various patterns of these studies, we need to carefully consider the therapeutic methods. Compared to the cost needed for these modalities, recently developed and approved Perflubutane- (Sonazoid-) based contrast agent enhanced ultrasonography is reasonable and safe. The major advantage is the real-time observation of the vascular structure and function of the Kupffer cells. By this procedure, we can carefully follow the tumor growth or character change in a hemangioma and decide the timing of therapeutic intervention, since abdominal pain, abdominal mass, consumptive coagulopathy, and hemangioma growth are the signs for the therapeutic intervention. We reviewed recent reports about Sonazoid-based enhancement and also showed the representative images collected in our department. This is the first review showing the detailed findings of the giant hemangiomas using Perflubutane (Sonazoid). This review will help the physician in making the decision, and we hope that Sonazoid will gain widespread acceptance in the near future.

Real-time observation of glomerular hemodynamic changes in diabetic rats: effects of insulin and ARB.

BACKGROUND: The progression of diabetic nephropathy is closely related to disturbances in glomerular hemodynamics, such as glomerular hypertension and/or hyperperfusion. The aim of this study was to observe and to analyze glomerular hemodynamics in rats with diabetes mellitus (DM) in vivo using confocal laser scan microscopy (CLSM). We also examined the effects of candesartan cilexetil (TCV-116), a selective angiotensin II type 1 receptor blocker (ARB), on glomerular hemodynamics in DM. METHODS: Munich-Wistar rats were divided into six groups: (1) four-day control; (2) four-day DM; (3) 28-day control; (4) 28-day DM; (5) DM treated with insulin; (6) DM treated with TCV-116. The kidney-to-body weight ratio, glomerular volume, and proteinuria were estimated. Glomerular hemodynamic changes were observed using CLSM and renal expression of endothelial nitric oxide synthase (eNOS), and neuronal nitric oxide synthase (nNOS) was evaluated by immunofluorescence. RESULTS: The kidney-to-body weight ratio, glomerular volume, the diameters of afferent arterioles (AA) and efferent arterioles (EA), erythrocyte velocities within glomeruli, and volume flow in glomerular capillary loops in four-day DM were significantly higher than in control rats, and increases were even more pronounced in the 28-day DM. TCV-116 treatment ameliorated all these findings and significantly decreased proteinuria, but there was no effect on the blood glucose level. On the other hand, insulin treatment was followed by normalization of all these changes induced in DM. Enhanced renal expression of eNOS in DM was suppressed when treated with either TCV-116 or insulin, while expression of nNOS was unaltered among the four groups. CONCLUSION: This imaging procedure allowed us to evaluate glomerular microcirculation in vivo, including the diameters of AA and EA, erythrocyte velocity, and volume flow. DM significantly induced glomerular hemodynamic alteration and renal hypertrophy. DM treated with either insulin or ARB ameliorated these changes. This study shows that progress in imaging technology promises to make major contributions to revealing the involvement of hemodynamic changes in glomerular diseases, aiding prognosis and the monitoring of therapeutic effects, as well.

Effect of high glucose on nitric oxide production and endothelial nitric oxide synthase protein expression in human glomerular endothelial cells.

BACKGROUND: Hyperglycemia directly contributes to the development of diabetic nephropathy. Nitric oxide (NO), a potent endothelium-derived vasodilator, has been suggested to participate in the regulation of renal blood flow, glomerular filtration rate, and mesangial matrix accumulation. Human vascular endothelial cells are known to exhibit functional heterogeneity, this prompted us to do the first study of NO bioavailability in human glomerular endothelial cells (HGECs), in response to high glucose exposure. METHODS: NO release was examined by detecting nitrite generation by the Griess assay in HGECs exposed to control-level (5.5 mM) and high-level (15, 30 and 60 mM) glucose solutions at various time periods (24, 48 and 72 h) in the presence or absence of L-arginine (1 mM), or superoxide dismutase (SOD) (250 U/ml). In addition, we evaluated the effect of glucose on the expression of endothelial nitric oxide synthase (eNOS) in HGECs by Western blotting. RESULTS: Final levels of nitrite generated in HGECs were reduced significantly, in a time- and concentration-dependent manner, after high glucose exposure. However, Western blot analysis revealed that eNOS protein expression was significantly upregulated at 12 h after exposure to high glucose concentrations (30 mM), reaching a peak at 48 h (twofold increase over baseline levels). The inhibitory effect of high glucose on NO production was restored by the addition of SOD. Addition of L-arginine (1 mM) to external media also reversed the inhibitory effect of high glucose on NO production of HGECs as well. CONCLUSIONS: The present study demonstrated that high glucose increased eNOS protein expression, but decreased NO release finally. Decreased NO bioavailability seems to be associated with overproduction of superoxide and L-arginine deficiency. These findings provide an important clue in clarifying the molecular basis of the mechanisms by which elevated glucose leads to an imbalance between NO and superoxide, resulting in impaired endothelial function. In addition, restoration of NO function by both administration of L-arginine and adequate intake of antioxidants suggests a potential supportive treatment for patients with diabetic nephropathy.