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Background: The sudden urge to urinate, also known as overactive bladder (OAB), may reflect higher sympathetic activity and associate with higher blood pressure (BP)., Methods: This cross-sectional analysis utilized data from sixth follow-up exam (2015-2016) of Multi-Ethnic Study of Atherosclerosis to examine the association of OAB with systolic (SBP) and diastolic blood pressure (DBP) levels, hypertension, and BP control. Information on urinary symptoms was obtained with the International Consultation on Incontinence Questionnaire (ICIQ). Sex-stratified regression models were constructed to examine differences in BP, hypertension prevalence, and BP control while adjusting for demographic factors, comorbidities, and medication use., Results: Among the 1,446 men and 1,628 women who completed the ICIQ (mean age 73.7 years [SD 8.4]), OAB was present in 31.6% of men and 38.9% of women. With no antihypertensive medication use, OAB was not associated with SBP or DBP in both men and women after adjusting for covariates. However, among the 894 men and 981 women on antihypertensive medication, OAB was associated with higher SBP among men (4.04 mm Hg; 95% confidence interval [CI] 1.02, 7.06) but not among women (-0.67 mm Hg; 95% CI -3.79, 2.46) while DBP did not differ by OAB presence in men or women. In addition, OAB was also associated with lower odds of BP control among men (odds ratio [OR] 0.69; 95% CI 0.49, 0.96) but not women (OR 0.96; 95% CI 0.71, 1.30)., Conclusions: Among men, OAB is associated with lower odds of BP control which suggests that OAB may impede hypertension management., (© American Journal of Hypertension, Ltd 2021. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: While changes in blood pressure (BP) are independently associated with cardiovascular events, less is known about the association between changes in BP and subsequent changes in renal function in adults with an estimated glomerular filtration rate (eGFR) of >60 ml/min/1.73 m2., Methods: The present study included 3,920 participants in the Multi-Ethnic Study of Atherosclerosis (MESA) study who had ≥2 BP measurements during the first 5 years of MESA and had eGFR measurements at both year 5 and 10. Change in BP was estimated as the annualized slope of BP between year 0 and 5 based on linear mixed models (mean number of measurements = 4.0). Participants were then grouped into 1 of 3 categories based on the distribution of systolic BP (SBP), diastolic BP (DBP), and pulse pressure (PP) change (top 20%, middle 21-79%, bottom 20%). We calculated eGFR from cystatin C (ml/min/1.73 m2), estimated annual change in eGFR (ml/min/1.73 m2/year), and defined rapid kidney function decline as a >30% decrease in eGFR from year 5 to 10. We used multivariable logistic regression adjusting for year 0 demographic and clinical characteristics, including eGFR and BP, to determine associations of BP change with rapid kidney function decline., Results: Median age was 59 [interquartile range (IQR): 52, 67] and median eGFR at year 0 was 95.5 (IQR: 81.7, 105.9) ml/min/1.73 m2. Median SBP at year 0 was 111, 121, and 147 mm Hg for increasing, stable, and decreasing SBP change, respectively. Increasing SBP and widening PP change were each associated with higher odds of rapid kidney function decline compared with stable SBP and PP groups, respectively [odds ratio, OR 1.7 (95% confidence interval, CI 1.3, 2.4) for SBP; OR 1.4 (95% CI 1.1, 1.9) for PP]. Decreasing SBP was associated with rapid kidney function decline after adjusting for all covariates except for year 0 BP [OR 1.4 (95% CI 1.0, 1.8)], but this association was no longer statistically significant after adjustment for year 0 BP. There were no significant associations between DBP change and rapid decline in the fully adjusted models. Similar findings were seen with annual change in eGFR., Conclusions: Increasing SBP and widening PP over time were associated with greater risk for accelerated kidney function decline even at BP levels below established hypertension thresholds.

Background: Higher blood pressure during young adulthood may increase cardiovascular and kidney disease risk later in life. This study examined the association of cumulative systolic blood pressure (SBP) exposure during young adulthood through midlife with urine albumin-to-creatinine ratios (ACR) measured during midlife., Methods: We used data from the Coronary Artery Risk Development in Young Adults (CARDIA) study, a biracial cohort recruited in 4 urban areas during years 1985-1986. Cumulative SBP was calculated as the average SBP between 2 exams multiplied by years between exams over 20 year years. ACR was measured 20 years after baseline when participants were age 43-50 years (midlife). A generalized additive model was used to examine the association of log ACR as a function of cumulative SBP with adjustment for covariates including SBP measured concurrently with ACR., Results: Cumulative SBP ranged from a low of 1,671 to a high of 3,260 mm Hg. Participants in the highest cumulative SBP quartile were more likely to be male (61.4% vs. 20.7%; P < 0.001), Black (61.5% vs. 25.6%; P < 0.001) and have elevated ACR (18.7% vs. 4.8%; P < 0.001) vs. lowest quartile. Spline regression curves of ACR vs. cumulative SBP demonstrated an inflection point in ACR with cumulative SBP levels >2,350 mm Hg with linear increases in ACR above this threshold. Adjusted geometric mean ACR values were significantly higher with cumulative SBP ≥2,500 vs. <2500 (9.18 [1.06] vs. 6.92 [1.02]; P < 0.0001)., Conclusion: Higher SBP during young adulthood through midlife is associated with higher ACR during midlife., (© American Journal of Hypertension, Ltd 2017. All rights reserved. For Permissions, please email: journals.permissions@oup.com)

Background: Recent experimental evidence suggests that DNA damage and cell cycle regulatory proteins are involved in kidney injury and apoptosis. The checkpoint 2 gene (CHEK2) is an important transducer in DNA damage signaling pathways in response to injury, and therefore, CHEK2 variants may affect susceptibility to kidney disease., Methods: We used tag-single-nucleotide polymorphisms (tag-SNPs) to evaluate the association of the CHEK2 with kidney function (estimated glomerular filtration rate, eGFR) in 1,549 African-American and 1,423 white Hypertension Genetic Epidemiology Network (HyperGEN) participants. We performed replication analyses in the Genetic Epidemiology Network of Arteriopathy (GENOA) participants (1,746 African Americans and 1,418 whites), GenNet participants (706 whites), and Atherosclerosis Risk in Communities (ARIC) study participants (3,783 African Americans and 10,936 whites). All analyses were race-stratified and used additive genetic models with adjustments for covariates and for family structure, if needed., Results: One tag-SNP, rs5762764, was associated with eGFR in HyperGEN (P = 0.003) and GENOA white participants (P = 0.009), and it was significantly associated with eGFR in meta-analyses (P = 0.002). The associations were independent of type 2 diabetes., Conclusions: These results suggest that CHEK2 variants may influence eGFR in the context of hypertension.

Endogenous ouabain-like factors (OLF) may play a role in the pathogenesis of volume-dependent hypertension by raising intracellular free calcium ([Ca2+]i) as a consequence of inhibition of the sodium pump. In previous studies we described the presence of two low molecular (Mr approximately equals 400) inhibitors of Na-K-ATPase in human urine, ie, a more polar OLF-1 and a more apolar OLF-2. We subsequently identified the active compound in OLF-2 as vanadium (V(IV))-diascorbate (Mr 416). OLF-1, OLF-2, and V-diascorbate inhibited dose-dependently porcine Na-K-ATPase in vitro. In the present study we investigated the effects of urinary OLF-1, OLF-2, and V-diascorbate on calcium mobilization, ie, on [Ca2+]i in cultured rat vascular smooth muscle (VSM) cells in comparison to the effects of ouabain, angiotensin II (A II), and arginine-vasopressin (AVP). [Ca2+]i was determined by the fura-2 method. OLF-1 and OLF-2 (each approximately equals 10(-4) mol/L), obtained as single spots by thin-layer chromatography, produced a rise in [Ca2+]i in VSM cells from 45 +/- 7 to 99 +/- 22 and from 48 +/- 9 to 92 +/- 2 nmol/L (each n = 5; P < .05), respectively, after 3 min. V-diascorbate also increased [Ca2+]i slowly and dose-dependently, eg, from 56 +/- 14 to 102 +/- 15 nmol/L at a concentration of 10(-6) mol/L (n = 5; P < .05) after 3 min. A similar slow rise in [Ca2+]i from 53 +/- 10 to 185 +/- 3 nM (n = 5; P < .05) after 3 min was found with ouabain (10(-6) mol/L). As standard vasoconstrictor, All (10(-8) mol/L) rapidly increased [Ca2+]i from 23 +/- 4 to 846 +/- 50 nmol/L (n = 7; P < .01) within 30 sec. This effect was enhanced to 1,389 +/- 161 nM (n = 7; P < .01) when VSM cells were preincubated with V-diascorbate (10(-6) mol/L) for 10 min. AVP (10(-7) mol/L) also rapidly increased [Ca2+]i to 418 +/-11 nmol/L within 30 sec (n = 7; P < .01). This effect was enhanced in the presence of OLF-2 (approximately equals 10(-4) mol/L) or ouabain (10(-6) mol/L) to 523 +/- 14 and 560 +/- 19 nmol/L, respectively (each n = 7); P < .01). The calcium channel blocker verapamil, the intracellular calcium release blocker TMB-8, and the unselective cation channel blocker Ni2+ partly blunted the A II- or AVP-induced rise in [Ca2+]i and prevented the OLF-2- and V-diascorbate-induced increase in [Ca2+]i. Thus, OLF-1, OLF-2 and V-diascorbate, the active component of OLF-2, reveal effects similar to those of ouabain on [Ca2+]i in VSM cells, ie, they produce a slow rise in [Ca2+]i subsequent to inhibition of the sodium pump. The physiologic and pathologic roles of these and additional OLF in body fluid and blood pressure regulation and in hypertension have yet to be evaluated.

It is speculated that ouabain-like factors (OLF) play a role in the pathogenesis of volume-dependent hypertension. In previous studies we isolated a more polar OLF-1 and a more apolar OLF-2 from the urine of healthy subjects after 5 days on a high sodium intake (>400 mmol/day) by gel chromatography (Sephadex G-25 and G-10) and reverse-phase HPLC. We subsequently identified the chemical structure of OLF-2 as vanadium (V(IV)) diascorbate. OLF-1, OLF-2, and vanadium diascorbate inhibited dose-dependently porcine Na-K-ATPase in vitro. Because the inner medullary collecting duct (IMCD) plays a crucial role in the long-term regulation of body fluid volume, in the present study we investigated the effects of urinary OLF-1 and OLF-2, and of vanadium diascorbate in comparison to ouabain and vasopressin (AVP) on calcium mobilization, ie, on free calcium concentration [Ca2+]i, in cultured porcine IMCD cells. [Ca2+]i was determined by the fura-2 method in IMCD cells isolated by hypotonic treatment and density gradient centrifugation from fresh porcine kidneys. Assuming an approximate molecular weight (MW) of 400 for OLF-1 and OLF-2, OLF-1 (10(-4) mol/L) produced a slow increase in [Ca2+]i from 39 +/- 10 to 169 +/- 21 nmol/L (n = 7 ) after 4 min. Similarly, OLF-2 (10(-4) mol/L) resulted in an increase in [Ca2+]i from 74 +/- 20 to 216 +/- 52 nmol/L (n = 7) after 4 min. Vanadium diascorbate (MW 403) dose-dependently increased [Ca2+]i . At a concentration of 10(-6) mol/L it increased [Ca2+]i from 46 +/- 5 to 149 +/- 9 nmol/L (n = 5) after 4 min. A similar slow increase in [Ca2+]i was found with ouabain (10(-6) mol/L), which increased [Ca2+]i from 61 +/- 22 to 180 +/- 29 nmol/L (n = 5) after 4 min in contrast to AVP (10(-7) mol/L), which rapidly increased [Ca2+]i from 48 +/- 10 to 299 +/- 32 nmol/L (n = 4) within 30 sec. Thus, OLF-1, OLF-2, and Vanadium diascorbate, the active component of OLF-2, reveal similar effects as ouabain on IMCD cells, ie, they produce a slow increase in [Ca2+]i as expected from inhibition of Na-K-ATPase. The physiologic or pathologic roles of these and additional OLF in body fluid and blood pressure regulation and in hypertension have yet to be evaluated.

A rise in blood pressure is the main side effect of erythropoietin (EPO) treatment in patients with renal anemia. The mechanisms, however, by which EPO may cause hypertension are still unclear. We therefore investigated the effects of EPO on endothelin (ET) synthesis and cytosolic free calcium concentration ([Ca2+]i) in vascular endothelial cells. Porcine endothelial cells were isolated from thoracic aorta, pulmonary artery, and vena cava. Studies were performed with cells of the first subculture. ET concentrations were measured radioimmunologically. Changes in [Ca2+]i were determined with the fluorescent probe fura-2. Cytotoxicity was assessed by sodium 3'-[1-(phenyl-amino-carbonyl)-3,4-tetrazolium]-bis(4-methoxy-6-nitro)ben zene sulfonic acid hydrate (XTT) assay. ET synthesis was similar in cells of different vascular origins and was time-dependent, reaching approximately 2 pmol ET/mg protein within 12 h of incubation. EPO (12 to 200 U/mL) stimulated ET release time- and dose-dependently by up to 83.2% (P < .01) within 12 h in the absence of fetal calf serum and heparin. EPO induced an immediate significant rise in [Ca2+]i from 58 +/- 12 nmol/L to 495 +/- 85 nmol/L (P < .01) with a subsequent slow return to 257 +/- 3 nmol/L. During 2 h of incubation, the Ca-ionophore A 23187 (10(-8) mol/L) moderately but significantly stimulated endothelial ET synthesis. However, the Ca-channel blocker verapamil, the intracellular Ca-release blocker TMB-8, and nickel, an unspecific calcium channel blocker, had no consistent effects on [Ca2+]i or ET synthesis. The protein kinase C inhibitor H-7 stimulated basal [Ca2+]i and cellular ET synthesis. The tyrosine kinase inhibitor genistein suppressed the EPO-induced rise in [Ca2+]i and cellular ET synthesis. From these data we conclude that EPO may stimulate ET synthesis in vascular endothelial cells by activation of an EPO-receptor and via intracellular signalling mechanisms that comprise tyrosine kinase activation and a rise in [Ca2+]i. Therefore, the systemic hypertensive effects of EPO may be due at least in part to local stimulation of vascular endothelial ET synthesis via calcium mobilization.

In six patients with essential hypertension (EH) and in six healthy volunteers (C) the effects of a 60-min intravenous (iv) infusion of human atrial natriuretic peptide (alpha-hANP) (24 ng/min/kg) on systemic and renal hemodynamics and renal excretory function were evaluated. Basal plasma ANP concentrations in patients with EH were higher (P less than .05) than in C (30.9 +/- 4.5 v14.0 +/- 1.7 pmol/L). Maximal effects of alpha-hANP infusion occurred after 30 to 60 min. Blood pressure (BP) declined from 154 +/- 5/109 +/- 4 to 139 +/- 7/94 +/- 4 in EH and from 117 +/- 1/72 +/- 2 to 106 +/- 1/65 +/- 3 mm Hg in C (P less than .05). Cardiac output (CO) increased transiently from 6.1 +/- 0.3 to 6.5 +/- 0.4 L/min in EH and from 6.8 +/- 0.3 to 7.2 +/- 0.5 L/min in C, whereas heart rate (HR) remained constant both in patients with EH and in C (69 +/- 3 to 72 +/- 5 and 60 +/- 3 to 63 +/- 3/min). The increases in urine flow and in urinary sodium excretion from 3.6 +/- 0.2 to 16.0 +/- 2.0 mL/min and from 230 +/- 33 to 1004 +/- 137 mumol/min, respectively, in EH were more pronounced than in C (from 3.9 +/- 1.0 to 8.4 +/- 0.8 mL/min and from 211 +/- 37 to 451 +/- 84 mumol/min); (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)

An endogenous ouabain-like sodium pump inhibitor was demonstrated originally in serum or plasma of acutely extracellular fluid volume (ECFV) expanded animals and humans. Since then numerous studies have confirmed the presence of ouabain-like factor(s) (OLF) in blood, urine, cerebrospinal fluid, and various tissues including the heart and hypothalamus. Some of these OLFs represent well-known endogenous compounds, eg, free unsaturated fatty acids, which in vitro exhibit inhibition of transepithelial sodium transport, direct inhibition of the Na-K-ATPase enzyme, displacement of 3H-ouabain from its membrane receptor, and crossreaction with a digoxin antibody. Small molecular weight (MW) OLFs of yet unknown peptidic or nonpeptidic nature, which may be of hypothalamic origin, were also detected in various animal models of hypertension and in hypertensive patients. They may play a pathophysiological role especially in salt- and volume-dependent forms of hypertension. Our results show that OLFs increase basal and vasopressin-stimulated intracellular Ca2+ release in rat vascular smooth muscle cells in culture and in human platelets similar to the newly discovered endothelin. In addition, a natriuretic factor (natriuretic hormone) was detected by bioassay in plasma and urine, whose activity changes in parallel with sodium intake. We found that this natriuretic factor is associated with small peptides with a MW of less than 1,000. It is, however, unlikely that the two biological properties, ie, the ouabain-like and natriuretic activities, reside in a single compound. A number of circulating OLFs is certainly not identical with a humoral natriuretic factor. Nevertheless, there is increasing evidence for multiple interactions between OLF and the atrial natriuretic peptide (ANP).(ABSTRACT TRUNCATED AT 250 WORDS)