Direct comparison of the reproducibility of in-office and self-measured home blood pressures.

OBJECTIVE: The aim was to compare short-term and long-term reproducibilities of in-office unattended blood pressure (BP), namely automated office blood pressure (AOBP), conventionally measured attended office BP, and self-measured home BP. METHODS: A multicentre, clinical study was conducted in Japan, and 287 Japanese outpatients on antihypertensive drug medication were followed-up for 1 year. RESULTS: The intensity of drug treatment was sustained consistently throughout the study period (defined daily doses, 1.62-1.68; P = 0.12). The mean SBP differences between baseline and 1 month later, as well as baseline and 1 year later, were less than 1.5 mmHg, whereas the standard deviations of the differences for home, AOBP, and attended office measurements for the 1-year interval were 7.7, 14.5, and 15.3 mmHg, respectively. The coefficients of variation were significantly smaller for home BP than for AOBP among all patients at both 1-month and 1-year intervals (P < 0.0001). In the 1-month interval, partial correlation coefficients of home BP (r, 0.73/0.88 for systolic/diastolic measures) were significantly higher than of conventional BP (r, 0.47/0.69). However, the correlations converged to the modest level regardless of BP information (r, 0.49-0.54/0.63-0.73) when the 1-year interval was assessed. Results were confirmatory when patients on the same drug regimen (n = 167) were analysed. CONCLUSION: A higher reproducibility of home BP was demonstrated compared with in-office BP, including AOBP. However, the modest correlations for the 1-year interval support the importance of regular assessment of BP, regardless of in-office or home measurements for treatment of hypertension.

Effects of the chelating agent DTPA on naturally accumulating metals in the body.

Diethylenetriaminepentaacetate (DTPA) is the most widely used chelating agent for Pu and Am. Volunteers were assigned to receive intravenous injections or aerosol inhalations of 1 g of DTPA on days 1-4; volunteers received once daily injections of CaDTPA or ZnDTPA, CaDTPA inhalation as an aerosol, or CaDTPA injection on day 1 and ZnDTPA on days 2-4. CaDTPA injection or inhalation increased the excretion rates of Zn in urine with concomitantly reduced levels of serum Zn. Injection of CaDTPA reduced activities of serum alkaline phosphatase (AP) in parallel with the kinetics of Zn, whereas CaDTPA and ZnDTPA injection reduced activities of lactate dehydrogenase (LDH), and reduced activities of creatinine kinase (CK) were observed upon CaDTPA injection and its inhalation. Intravenous administration of CaDTPA and ZnDTPA enhanced excretion rates of Mn in urine, whereas transient reduction of Mn levels in serum was detected only via CaDTPA injection. Both CaDTPA and ZnDTPA transiently reduced levels of Mg in serum without affecting the excretion rates. On the other hand, both DTPAs increased excretion rates of toxic metals such as Pb and Cd, and CaDTPA also increased the rates of Hg. These results suggest that DTPA, and especially CaDTPA, removes essential metals and that the activities of these metalloenzymes are good indicators for the imbalance of essential metals during the DTPA administration. Our results also show that CaDTPA injection is more potent for removing these metals than ZnDTPA and inhalation of CaDTPA, and DTPA may be useful for the treatment of acute heavy metal poisoning with Pb, Cd, or Hg.

Effect of Standard vs Intensive Blood Pressure Control on the Risk of Recurrent Stroke: A Randomized Clinical Trial and Meta-analysis.

IMPORTANCE: The Systolic Blood Pressure Intervention Trial (SPRINT) demonstrated that a systolic blood pressure (BP) target less than 120 mm Hg was superior to less than 140 mm Hg for preventing vascular events. This trial excluded patients with prior stroke; therefore, the ideal BP target for secondary stroke prevention remains unknown. OBJECTIVE: To assess whether intensive BP control would achieve fewer recurrent strokes vs standard BP control. DESIGN, SETTING, AND PARTICIPANTS: Randomized clinical trial (RCT) of standard vs intensive BP control in an intent-to-treat population of patients who had a history of stroke. Patients were enrolled between October 20, 2010, and December 7, 2016. For an updated meta-analysis, PubMed and the Cochrane Central Library database were searched through September 30, 2018, using the Medical Subject Headings and relevant search terms for cerebrovascular disease and for intensive BP lowering. This was a multicenter trial that included 140 hospitals in Japan; 1514 patients who had a history of stroke within the previous 3 years were approached, but 234 refused to give informed consent. INTERVENTIONS: In total, 1280 patients were randomized 1:1 to BP control to less than 140/90 mm Hg (standard treatment) (n = 640) or to less than 120/80 mm Hg (intensive treatment) (n = 640). However, 17 patients never received intervention; therefore, 1263 patients assigned to standard treatment (n = 630) or intensive treatment (n = 633) were analyzed. MAIN OUTCOMES AND MEASURES: The primary outcome was stroke recurrence. RESULTS: The trial was stopped early. Among 1263 analyzed patients (mean [SD] age, 67.2 [8.8] years; 69.4% male), 1257 of 1263 (99.5%) completed a mean (SD) of 3.9 (1.5) years of follow-up. The mean BP at baseline was 145.4/83.6 mm Hg. Throughout the overall follow-up period, the mean BP was 133.2/77.7 (95% CI, 132.5-133.8/77.1-78.4) mm Hg in the standard group and 126.7/77.4 (95% CI, 125.9-127.2/73.8-75.0) mm Hg in the intensive group. Ninety-one first recurrent strokes occurred. Nonsignificant rate reductions were seen for recurrent stroke in the intensive group compared with the standard group (hazard ratio [HR], 0.73; 95% CI, 0.49-1.11; P = .15). When this finding was pooled in 3 previous relevant RCTs in a meta-analysis, the risk ratio favored intensive BP control (relative risk, 0.78; 95% CI, 0.64-0.96; P = .02; absolute risk difference, -1.5%; 95% CI, -2.6% to -0.4%; number needed to treat, 67; 95% CI, 39-250). CONCLUSIONS AND RELEVANCE: Intensive BP lowering tended to reduce stroke recurrence. The updated meta-analysis supports a target BP less than 130/80 mm Hg in secondary stroke prevention. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01198496.

Comparison of blood pressure values-self-measured at home, measured at an unattended office, and measured at a conventional attended office.

Self-measured blood pressure (BP) at home (HBP) has been commonly used in clinical practice. Although the unattended office BP (UBP), in which a patient is left alone before and during the measurement, has been investigated, the advantages of UBP over HBP or conventionally measured attended office BP obtained using automated devices (CBP) remain unclear. We performed a multicenter clinical study in Japan to compare the UBP, CBP, and HBP among 308 patients with hypertension at 3 clinics (women, 57.8%; mean age 71.8 years; under antihypertensive drug therapy, 96.4%). The patients measured HBP twice in the morning and twice in the evening for 5 days according to the Japanese Society of Hypertension guidelines. Using the Omron HEM-907 cuff-oscillometric device, the UBP and CBP were measured in line with the protocol in the Systolic blood PRessure INtervention Trial (SPRINT) and in accordance with the guidelines, respectively. Correlation coefficients were ≤0.16 for the comparison of UBP versus morning and evening HBP for the systolic measurement, whereas they were approximately 0.5 (P < 0.001) for the diastolic measurement. The difference between UBP minus HBP was small on average but varied among individuals (mean ± SD for UBP minus morning HBP: 0.9 ± 17.8/-4.5 ± 10.5 mmHg; UBP minus evening HBP: 5.7 ± 17.8/-0.1 ± 11.3 mmHg). In contrast, the measurement values of CBP and UBP were highly correlated (r ≥ 0.72), but the difference between CBP minus UBP was 10.4 ± 12.0/4.2 ± 6.5 mmHg. Based on the low correlations and wide range of differences, UBP cannot be used as an alternative to HBP.

Reduced secretion of parathyroid hormone and hypocalcemia in systemic heterozygous ATP2B1-null hypertensive mice.

The ATP2B1 gene is associated with hypertension. We previously reported that systemic heterozygous ATP2B1-null (ATP2B1+/-) mice exhibited hypertension due to impaired endothelial nitric oxide synthase (eNOS) activity and decreased nitric oxide (NO) production. The ATP2B1 gene encodes plasma membrane calcium ATPase 1 (PMCA1), which has been thought to regulate only intracellular Ca2+ concentration. However, recently, it has been suggested that ATP2B1 works not only at cellular levels, but also throughout the entire body, including in the calcium metabolism, using small intestine-specific ATP2B1 knockout mice. To clarify the roles of ATP2B1 in the entire body and the effects of ATP2B1 on blood pressure, we examined the alterations of calcium related factors in ATP2B1+/- mice. ATP2B1+/- mice exhibited hypocalcemia. The expression of ATP2B1 in the kidney and small intestine decreased, and hypercalciuria was confirmed in ATP2B1+/- mice. The intact-PTH levels were lower, and bone mineral density was increased in these mice. These results suggest that hypocalcemia is mainly a result of inhibited bone resorption without compensation by PTH secretion in the case of ATP2B1 knockout. Moreover, NO production may be affected by reduced PTH secretion, which may cause the increase in vascular contractility in these mice. The ATP2B1 gene is important for not only intra-cellular calcium regulation but also for calcium homeostasis and blood pressure control.

Atherosclerosis of the carotid bulb is associated with the severity of orthostatic hypotension in non-diabetic adult patients: a cross-sectional study.

BACKGROUND: The carotid bulb has a high density of baroreceptors that play an important role in maintaining blood pressure. We hypothesized that atherosclerosis of the carotid bulb would reflect the severity of orthostatic hypotension more accurately than would atherosclerosis of other carotid artery segments. METHODS: This cross-sectional study included 198 non-diabetic adults. We measured the cardio-vascular ankle index as an index of arterial stiffness, intima-media thickness in each carotid artery segment (internal carotid artery, carotid bulb, distal and proximal portions, respectively, of the common carotid artery) as a measure of atherosclerosis, and heart rate variability as a measure of cardiac autonomic function. The sit-to-stand test was used to assess severity of orthostatic hypotension. RESULTS: Intima-media thickness of the carotid bulb was correlated with orthostatic systolic blood pressure change (r = -0.218, p = 0.002), cardio-ankle vascular index (r = 0.365, p < 0.001) and heart rate variability parameters. Multivariate regression analysis revealed that among all of the segments, only intima-media thickness of the carotid bulb was an independent predictor of orthostatic systolic blood pressure change (p = 0.022). CONCLUSION: Atherosclerosis of the carotid bulb was associated with severity of orthostatic hypotension, arterial stiffening and cardiac autonomic dysfunction than that of other carotid artery segments.

The effects of anti-hypertensive drugs and the mechanism of hypertension in vascular smooth muscle cell-specific ATP2B1 knockout mice.

ATP2B1 is a gene associated with hypertension. We reported previously that mice lacking ATP2B1 in vascular smooth muscle cells (VSMC ATP2B1 KO mice) exhibited high blood pressure and increased intracellular calcium concentration. The present study was designed to investigate whether lack of the ATP2B1 gene causes a higher response to calcium channel blockers (CCBs) than to other types of anti-hypertensive drugs. Both VSMC ATP2B1 KO and control mice were administered anti-hypertensive drugs while monitoring blood pressure shifts. We also examined the association of nitric oxide synthase (NOS) activity in those mice to investigate whether another mechanism of hypertension existed. VSMC ATP2B1 KO mice exhibited significantly greater anti-hypertensive effects with a single injection of nicardipine, but the effects of an angiotensin II receptor blocker (ARB), an α-blocker and amlodipine on blood pressure were all similar to control mice. However, long-term treatment with amlodipine, but not an ARB, significantly decreased the blood pressure of KO mice compared with control mice. Both mRNA and protein expression levels of the L-type calcium channel were significantly upregulated in KO VSMCs. There were no alterations in neural NOS protein expression of VSMCs or in urinary NO production between the two groups. VSMC ATP2B1 KO mice had a higher response to CCBs for blood pressure-lowering effects than other anti-hypertensive drugs. These results mean that increased intracellular calcium concentration in VSMCs due to lack of ATP2B1 and subsequent activation of L-type calcium channels mainly affects blood pressure and suggests increased susceptibility to CCBs in this type of hypertension.

Arterial wall hypertrophy is ameliorated by α2-adrenergic receptor antagonist or aliskiren in kidneys of angiotensinogen-knockout mice.

BACKGROUND: Arterial hypertrophy and interstitial fibrosis are important characteristics in kidneys of angiotensinogen-knockout (Atg -/-) mice. In these mice, which exhibit polyuria and hypotension, sympathetic nerve signaling is estimated to be compensatorily hyperactive. Furthermore, transforming growth factor (TGF)-ß1 is overexpressed in mice kidneys. To determine whether sympathetic nerve signaling and TGF-ß1 exacerbate arterial hypertrophy and interstitial fibrosis, intervention studies of such signaling are required. METHODS: We performed renal denervation and administered the α2-adrenergic receptor (AR) antagonist, atipamezole, to Atg -/- mice. A renin inhibitor, aliskiren, which was preliminarily confirmed to reduce TGF-ß1 gene expression in kidneys of the mice, was additionally administered to assess the effect on the arterial hypertrophy and interstitial fibrosis. RESULTS: Norepinephrine content in kidneys of Atg -/- mice was three times higher than in kidneys of wild-type mice. Interventions by renal denervation and atipamezole resulted in amelioration of the histological findings. Overexpression of TGF-ß1 gene in kidneys of Atg -/- mice was altered in a manner linked to the histological findings. Surprisingly, aliskiren reduced α2-AR gene expression, interstitial fibrosis, and arterial hypertrophy in kidneys of Atg -/- mice, which lack renin substrate. CONCLUSIONS: Alpha2-AR signaling is one of the causes of persistent renal arterial hypertrophy in Atg -/- mice. Aliskiren also angiotensinogen-independently reduces the extent of renal arterial hypertrophy, partly thorough downregulation of α2-ARs. Although renal arterial hypertrophy in Atg -/- mice appears to be of multifactorial origin, TGF-ß1 may play a key role in the persistence of such hypertrophy.

L-DOPA sensitizes vasomotor tone by modulating the vascular alpha1-adrenergic receptor.

Blood pressure is regulated by extrinsic factors including noradrenaline, the sympathetic neurotransmitter that controls cardiovascular functions through adrenergic receptors. However, the fine-tuning system of noradrenaline signaling is relatively unknown. We here show that l-3,4-dihydroxyphenylalanine (L-DOPA), a precursor of catecholamines, sensitizes the vascular adrenergic receptor alpha1 (ADRA1) through activation of L-DOPA receptor GPR143. In WT mice, intravenous infusion of the ADRA1 agonist phenylephrine induced a transient elevation of blood pressure. This response was attenuated in Gpr143 gene-deficient (Gpr143-/y) mice. Specific knockout of Gpr143 in vascular smooth muscle cells (VSMCs) also showed a similar phenotype, indicating that L-DOPA directly modulates ADRA1 signaling in the VSMCs. L-DOPA at nanomolar concentrations alone produced no effect on the VSMCs, but it enhanced phenylephrine-induced vasoconstriction and intracellular Ca2+ responses. Phenylephrine also augmented the phosphorylation of extracellular signal-regulated kinases in cultured VSMCs from WT but not Gpr143-/y mice. In WT mice, blood pressure increased during the transition from light-rest to dark-active phases. This elevation was not observed in Gpr143-/y mice. Taken together, our findings provide evidence for L-DOPA/GPR143 signaling that exerts precursor control of sympathetic neurotransmission through sensitizing vascular ADRA1.

Prolonged Fever After ST-Segment Elevation Myocardial Infarction and Long-Term Cardiac Outcomes.

BACKGROUND: The biphasic inflammation after ST-segment elevation myocardial infarction (STEMI) plays an important role in myocardial healing and progression of systemic atherosclerosis. The purpose of this study is to investigate the impact of fever during the first and second phases of post-STEMI inflammation on long-term cardiac outcomes. METHODS AND RESULTS: A total of 550 patients with STEMI were enrolled in this study. Axillary body temperature (BT) was measured and maximum BTs were determined for the first (within 3 days: max-BT1-3d) and second (from 4 to 10 days after admission: max-BT4-10d) phases, respectively. Patients were followed for cardiac events (cardiovascular death, acute coronary syndrome, and rehospitalization for heart failure) for a median 5.3 years. During the follow-up period, 80 patients experienced cardiac events. A high max-BT4-10d was strongly associated with long-term cardiac events (hazard ratio, 95% CI) for a 1°C increase in the max-BT4-10d: 2.834 (2.017-3.828), P<0.0001, whereas the max-BT1-3d was not associated with cardiac events (1.136 [0.731-1.742], P=0.57). Even after adjustment for coronary risk factors, estimated glomerular filtration rate, infarct size, pericardial effusion, and medications on discharge, fever during the second phase (max-BT4-10d ≥37.1°C) was significantly associated with future cardiac events (hazard ratio [95% CI] 2.900 [1.710-5.143], P<0.0001). CONCLUSIONS: Fever during the second phase but not the first phase of post-STEMI inflammation was a strong associated factor with worse long-term cardiac outcomes in patients after STEMI, suggesting the need to consider the optimal timing for anti-inflammatory strategies after STEMI.

Angiotensin II Type 1 Receptor-Associated Protein Regulates Kidney Aging and Lifespan Independent of Angiotensin.

BACKGROUND: The kidney is easily affected by aging-associated changes, including glomerulosclerosis, tubular atrophy, and interstitial fibrosis. Particularly, renal tubulointerstitial fibrosis is a final common pathway in most forms of progressive renal disease. Angiotensin II type 1 receptor (AT1R)-associated protein (ATRAP), which was originally identified as a molecule that binds to AT1R, is highly expressed in the kidney. Previously, we have shown that ATRAP suppresses hyperactivation of AT1R signaling, but does not affect physiological AT1R signaling. METHODS AND RESULTS: We hypothesized that ATRAP has a novel functional role in the physiological age-degenerative process, independent of modulation of AT1R signaling. ATRAP-knockout mice were used to study the functional involvement of ATRAP in the aging. ATRAP-knockout mice exhibit a normal age-associated appearance without any evident alterations in physiological parameters, including blood pressure and cardiovascular and metabolic phenotypes. However, in ATRAP-knockout mice compared with wild-type mice, the following takes place: (1) age-associated renal function decline and tubulointerstitial fibrosis are more enhanced; (2) renal tubular mitochondrial abnormalities and subsequent increases in the production of reactive oxygen species are more advanced; and (3) life span is 18.4% shorter (median life span, 100.4 versus 123.1 weeks). As a key mechanism, age-related pathological changes in the kidney of ATRAP-knockout mice correlated with decreased expression of the prosurvival gene, Sirtuin1. On the other hand, chronic angiotensin II infusion did not affect renal sirtuin1 expression in wild-type mice. CONCLUSIONS: These results indicate that ATRAP plays an important role in inhibiting kidney aging, possibly through sirtuin1-mediated mechanism independent of blocking AT1R signaling, and further protecting normal life span.

Enhancement of intrarenal plasma membrane calcium pump isoform 1 expression in chronic angiotensin II-infused mice.

Plasma membrane calcium pump isoform 1 (PMCA1) is encoded by ATPase plasma membrane Ca2+transporting 1 (ATP2B1), the most likely candidate gene responsible for hypertension. Although PMCA1 is highly expressed in the kidney, little is known about regulation of its renal expression in various pathological conditions in vivo. Our study was designed to elucidate regulation of renal PMCA1 expression in mice. We employed three mouse models for kidney disease. These were the unilateral ureteral obstruction (UUO), the remnant kidney using 5/6 nephrectomy, and chronic angiotensin II administration models. Mice were assessed for systolic blood pressure and renal injury in accordance with the damage induced in the specific model. Kidney PMCA1 mRNA levels were measured in all mice. The UUO model showed renal fibrosis but no changes in blood pressure or renal PMCA1 mRNA expression. Similarly, the 5/6 nephrectomy model exhibited declined renal function without changes in blood pressure or renal PMCA1 mRNA expression. In contrast, chronic angiotensin II administration increased albuminuria and blood pressure as well as significantly increasing renal PMCA1 mRNA and protein expression. These results suggest that renal PMCA1 has a role as one of the molecules involved in angiotensin II-induced hypertension and kidney injury.

Within-visit blood pressure variability and cardiovascular risk factors in hypertensive patients with non-dialysis chronic kidney disease.

As there may be an association between within-visit blood pressure (BP) variability and cardiovascular disease (CVD), we investigated the clinical significance of this BP variability in non-dialysis chronic kidney disease (CKD) patients. MATERIALS AND METHODS: According to the median of coefficient of variation (CV) of three systolic BP (SBP) readings within a single visit, we divided hypertensive patients with stage G1-4 CKD already treated with antihypertensive therapy into the high SBP-CV group and the low SBP-CV group. Univariate and multivariate linear regression analyses were also performed to explore the contributing factors to within-visit BP variability. RESULTS: In the high SBP-CV group, the clinic BP, total cholesterol level, dyslipidemia, and past history of CVD were significantly greater, while α1-blockers and renin-angiotensin system (RAS) inhibitors usage were significantly reduced compared with the lower SBP-CV group. Within-visit BP variability was significantly and positively correlated with total cholesterol (R = 0.392, P < 0.001) and low-density lipoprotein cholesterol (R = 0.284, P = 0.013). Total cholesterol (ß = 0.269, P = 0.024), α1-blockers usage (ß = -0.260, P = 0.015), and RAS inhibitors usage (ß = -0.266, P = 0.017) were shown to independently contribute to the within-visit BP variability after adjustment for age, sex, presence of diabetes, CVD history, statins usage, and clinic SBP. CONCLUSIONS: We show that within-visit BP variability may be a clinically relevant factor of CVD risk, and lipid lowering and/or anti-hypertensive therapies using RAS inhibitors and α1-blockers may be associated with the improved within-visit BP variability observed in non-dialysis CKD patients.

Adipocyte-Specific Enhancement of Angiotensin II Type 1 Receptor-Associated Protein Ameliorates Diet-Induced Visceral Obesity and Insulin Resistance.

BACKGROUND: The renin-angiotensin system has a pivotal role in the pathophysiology of visceral obesity. Angiotensin II type 1 receptor (AT1R) is a major player in the signal transduction of the renin-angiotensin system, and the overactivation of this signaling contributes to the progression of visceral obesity. We have shown that the AT1R-associated protein (ATRAP) promotes AT1R internalization from the cell surface into cytoplasm along with the suppression of overactivation of tissue AT1R signaling. In this study, we examined whether the enhancement of adipose ATRAP expression could efficiently prevent diet-induced visceral obesity and insulin resistance. METHODS AND RESULTS: We generated adipocyte-specific ATRAP transgenic mice using a 5.4-kb adiponectin promoter, and transgenic mice and littermate control mice were fed either a low- or high-fat diet for 10 weeks. Although the physiological phenotypes of the transgenic and control mice fed a low-fat diet were comparable, the transgenic mice exhibited significant protection against high-fat diet-induced adiposity, adipocyte hypertrophy, and insulin resistance concomitant with an attenuation of adipose inflammation, macrophage infiltration, and adipokine dysregulation. In addition, when mice were fed a high-fat diet, the adipose expression of glucose transporter type 4 was significantly elevated and the level of adipose phospho-p38 mitogen-activated protein kinase was significantly attenuated in the transgenic mice compared with control mice. CONCLUSIONS: Results presented in this study suggested that the enhancement in adipose ATRAP plays a protective role against the development of diet-induced visceral obesity and insulin resistance through improvement of adipose inflammation and function via the suppression of overactivation of adipose AT1R signaling. Consequently, adipose tissue ATRAP is suggested to be an effective therapeutic target for the treatment of visceral obesity.

ATRAP Expression in Brown Adipose Tissue Does Not Influence the Development of Diet-Induced Metabolic Disorders in Mice.

Activation of tissue renin-angiotensin system (RAS), mainly mediated by an angiotensin II (Ang II) type 1 receptor (AT1R), plays an important role in the development of obesity-related metabolic disorders. We have shown that AT1R-associated protein (ATRAP), a specific binding protein of AT1R, functions as an endogenous inhibitor to prevent excessive activation of tissue RAS. In the present study, we newly generated ATRAP/Agtrap-floxed (ATRAPfl/fl) mice and adipose tissue-specific ATRAP downregulated (ATRAPadipoq) mice by the Cre/loxP system using Adipoq-Cre. Using these mice, we examined the functional role of adipose ATRAP in the pathogenesis of obesity-related metabolic disorders. Compared with ATRAPfl/fl mice, ATRAPadipoq mice exhibited a decreased ATRAP expression in visceral white adipose tissue (WAT) and brown adipose tissue (BAT) by approximately 30% and 85%, respectively. When mice were fed a high-fat diet, ATRAPfl/fl mice showed decreased endogenous ATRAP expression in WAT that was equivalent to ATRAPadipoq mice, and there was no difference in the exacerbation of dietary obesity and glucose and lipid metabolism. These results indicate that ATRAP in BAT does not influence the pathogenesis of dietary obesity or metabolic disorders. Future studies that modulate ATRAP in WAT are necessary to assess its in vivo functions in the development of obesity-related metabolic disorders.

Effects of tolvaptan in patients with chronic kidney disease and chronic heart failure.

BACKGROUND: Tolvaptan, a vasopressin V2 receptor blocker, has a diuretic effect for patients with heart failure. However, there were a few data concerning the effects of tolvaptan in patients with chronic kidney disease (CKD). METHODS: We retrospectively analyzed 21 patients with chronic heart failure and CKD. Tolvaptan was co-administered with other diuretics in-use, every day. We compared clinical parameters before and after the treatments with tolvaptan. Furthermore, we examined the correlations between baseline data and the change of body weight. RESULTS: Tolvaptan decreased the body weight and increased the urine volume (p = 0.001). The urine osmolality significantly decreased throughout the study period. Urinary Na/Cr ratio and FENa changed significantly after 4 h, and more remarkable after 8 h (p = 0.003, both). Serum creatinine increased slightly after 1 week of treatment (p = 0.012). The alteration of body weight within the study period correlated negatively with the baseline urine osmolality (r = -0.479, p = 0.038), the baseline urine volume (r = -0.48, p = 0.028), and the baseline inferior vena cava diameter (IVCD) (r = -0.622, p = 0.017). Hyponatremia was improved to the normal value, and the augmentations of the sodium concentration were negatively associated with the basal sodium levels (p = 0.01, r = -0.546). CONCLUSIONS: Tolvaptan is effective in increasing diuresis and improved hyponatremia, even in patients with CKD. The baseline urine osmolality, urine volume, and IVCD may be useful predictors for diuretic effects of tolvaptan.

An angiotensin II type 1 receptor binding molecule has a critical role in hypertension in a chronic kidney disease model.

Angiotensin II type 1 receptor-associated protein (ATRAP) promotes AT1R internalization along with suppression of hyperactivation of tissue AT1R signaling. Here, we provide evidence that renal ATRAP plays a critical role in suppressing hypertension in a mouse remnant kidney model of chronic kidney disease. The effect of 5/6 nephrectomy on endogenous ATRAP expression was examined in the kidney of C57BL/6 and 129/Sv mice. While 129/Sv mice with a remnant kidney showed decreased renal ATRAP expression and developed hypertension, C57BL/6 mice exhibited increased renal ATRAP expression and resistance to progressive hypertension. Consequently, we hypothesized that downregulation of renal ATRAP expression is involved in pathogenesis of hypertension in the remnant kidney model of chronic kidney disease. Interestingly, 5/6 nephrectomy in ATRAP-knockout mice on the hypertension-resistant C57BL/6 background caused hypertension with increased plasma volume. Moreover, in knockout compared to wild-type C57BL/6 mice after 5/6 nephrectomy, renal expression of the epithelial sodium channel α-subunit and tumor necrosis factor-α was significantly enhanced, concomitant with increased plasma membrane angiotensin II type 1 receptor in the kidneys. Thus, renal ATRAP downregulation is involved in the onset and progression of blood pressure elevation caused by renal mass reduction, and implicates ATRAP as a therapeutic target for hypertension in chronic kidney disease.

A case of heparin-induced thrombocytopenia with subacute stent thrombosis, multiple cerebral infarction, and acute limb ischemia.

Heparin-induced thrombocytopenia (HIT) is an adverse immune-mediated drug reaction that is associated with thromboembolic complications. We report the case of an 82-year-old man with unstable angina pectoris who suffered from recurrent arterial thromboembolism due to HIT. Coronary angiography (CAG) was performed while we administered unfractionated heparin bolus. CAG showed triple-vessel disease without left main coronary artery. We performed elective percutaneous coronary angioplasty (PCI) to the left anterior descending coronary artery (LAD). The sudden thrombus formation in the LAD occurred during the procedure. We suspected HIT and administered argatroban. We deployed four everolimus-eluting stents in the LAD and intra-aortic balloon pumping (IABP) support was started. The platelet counts were rapidly reduced almost 50% next day after PCI and IgG-specific anti-PF4/heparin antibodies were elevated. Multiple cerebral infarctions were detected by magnetic resonance imaging after the PCI. The patient received the continuous argatroban administration and IABP support for 4 days. Subacute stent thrombosis occurred after quitting argatroban. We performed thrombus aspiration and fibrinolytic treatment. Finally we re-inserted IABP and stabilized the hemodynamic state. Right popliteal arterial thromboembolism occurred after emergency PCI. Argatroban is essential and following oral anticoagulant therapy is necessary to prevent thromboembolic complications. .