High sodium, rather than high blood pressure, induces immune cell activation and renal infiltration in ovariectomized adult Wistar rats.

We used an animal model of salt-sensitive hypertension (SSH) in which ovariectomized (oVx) rats developed hypertension with high salt (HS) intake. Hypertension is accompanied by changes in the percentage of CD4+ T lymphocytes, immune CD45+ cell infiltration into renal tissue, and changes in Na+, K+- ATPase (NKA) expression in both renal tissue and peripheral blood mononuclear cells (PBMCs). To determine whether the observed changes resulted from HS intake, high blood pressure, or both, hydralazine (HDZ) was used to lower blood pressure. The oVx HS rats received two HDZ schedules either to prevent or to treat hypertension. NKA was overexpressed in the kidneys of all oVx groups and in PBMCs of oVx HS rats. This pattern was not altered with HDZ treatment. Changes in CD4+ T lymphocytes and renal infiltration of CD45+ cells were not reversed either. High salt, but not high blood pressure, induces immune cell activation and renal infiltration. Overexpressed NKA is the primary event, and HS is the perturbation to the system in this model of SSH, which resembles the postmenopausal state.

Role of Female Sex Hormones and Immune Response in Salt-Sensitive Hypertension Development: Evidence from Experimental Models.

PURPOSEOF REVIEW: Female sex hormones have systemic effects unrelated to their reproductive function. We describe experiences of different research groups and our own, on aspects related to the importance of female sex hormones on blood pressure (BP) regulation and salt-sensitivity-mediated BP response and salt sensitivity without alterations in BP, as well as renal sodium handling and interactions with the immune system. RECENT FINDINGS: Changes in sodium intake in normotensive premenopausal women cause more BP variations than in men. After menopause, women often develop arterial hypertension (HT) with a profile of sodium sensitivity. Besides, experimental results have shown that in adult rat models resembling the postmenopausal hormonal state induced by ovariectomy, controlling BP is not enough to avoid renal and other tissue infiltration with immune cells, which does not occur when sodium intake is low or normal. Therefore, excess sodium promotes an inflammatory state with the involvement of immune cells. The evidence of activation of adaptive immunity, besides changes in T cell subpopulations, includes changes in sodium transporters and receptors. More studies are needed to evaluate the particular sodium sensitivity of women and its meaning. Changes in lifestyle and sodium intake reduction are the main therapeutic steps. However, to face the actual burden of salt-sensitive HT in postmenopausal women and its associated inflammatory/immune changes, it seems reasonable to work on immune cell activity by considering the peripheral blood mononuclear cell phenotypes of molecules and transport proteins related to sodium handle, both to screen for and treat cell activation.

Ovariectomy and high salt increase blood pressure and alter sodium transport proteins in peripheral blood mononuclear cells of adult Wistar rats.

NEW FINDINGS: What is the central question of this study? In a model of salt-sensitive hypertension in ovariectomized (oVx) adult Wistar rats, what is the expression of proteins related to sodium transport in peripheral blood mononuclear cells (PBMCs), and how does the response of proteins to high sodium intake compare with changes in blood pressure in intact female rats? What is the main finding and its importance? Sodium transport proteins in PBMCs react to high sodium and blood pressure markedly differently in oVx versus intact female rats. Protein expression shows sodium and pressure sensitivity. Renal immune cells increase in oVx under high salt. ABSTRACT: Hypertension is a worldwide public health problem. High sodium consumption is associated with hypertension, and hypertensive mechanisms involve immunity cells. Peripheral blood mononuclear cells (PBMCs) are endowed with proteins related to sodium transport. We studied their abundance in PBMCs from intact (IF) or ovariectomized (oVx) adult Wistar rats under normal (NS) or high (HS) salt intake. Ovariectomy was performed at 60 days of life. At 145 days, one group of IF and oVx rats received NS or HS intake for 5 days. Another group of IF HS and oVx HS rats received hydralazine (HDZ) to reduce blood pressure (BP). Sodium balance and BP were recorded. Expression of Na+ ,K+ -ATPase (NKA), Na+ -K+ -2Cl- cotransporter 1 (NKCC1), serum/glucocorticoid-regulated kinase 1 (SGK1), dopamine D1 like receptor (D1DR), CD4+ and CD8+ were determined in PBMCs and CD45+ leukocytes in renal tissue. IF HS rats showed increased natriuresis and normal BP. NKA and CD4+ expression diminished in IF HS. Instead, oVx HS rats had sodium retention and high BP and increased the expression of NKA, NKCC1, D1DR, CD4+ and CD8+ in PBMCs. Renal CD45+ leukocytes increased in oVx HS rats. HDZ decreased BP in all rats. Upon HDZ treatment, NKA did not change, NKCC1 decreased in oVx HS rats, while SGK1 increased in both IF HS and oVx HS rats. Hormonal background determines BP response and the expression of proteins related to sodium transport in PBMCs and renal immune cells at HS intake. The analysis of NKA, NKCC1 and SGK1 expression in PBMCs differentiated salt-sensitivity from BP variations.

Estradiol stimulates cell proliferation via classic estrogen receptor-alpha and G protein-coupled estrogen receptor-1 in human renal tubular epithelial cell primary cultures.

This work was aimed to determine the effect of 17ß-estradiol (17ßE) on cell proliferation in human renal tubular epithelial cells (HRTEC) isolated from kidneys from pediatric subjects, as well as the role of estrogen receptors involved in the 17ßE proliferative response. Treatment with 17ßE (10 nmol/L, 24 h) significantly stimulated cell proliferation, measured by 5-bromo-2-deoxyuridine (BrdU) uptake, in HRTEC primary cultures and in tubular structures obtained by 3D cultured-HRTEC. Incubation of HRTEC with the G protein-coupled estrogen receptor 1 (GPER-1) agonist G-1 increased BrdU uptake. Incubation of HRTEC with 17ßE activated the classic estrogen receptor alpha (ERα) but not ERß. Treatment of HRTEC with the GPER-1 antagonist G-15, the ER inhibitor ICI182,780, or the ß-catenin inhibitor iCRT14, completely abrogated the increase in BrdU uptake induced by 17ßE. We also show that 17ßE stimulated ß-catenin protein expression and translocation to the nucleus of HRTEC, effects that were abrogated by G-15 and ICI 182,780. In conclusion, estradiol stimulates cell proliferation in HRTEC primary cultures through both ERα and GPER-1 estrogen receptors and involves ß-catenin activation.

Maternal and perinatal complications in pregnant women with urinary tract infection caused by Escherichia coli.

AIM: The incidence of urinary tract infection (UTI) in pregnant women may vary from 5-10% and depends on parity, race, socioeconomic status and anatomical and functional changes in pregnancy. In Mexico, preterm birth accounts for 75% of perinatal deaths and 50% of the neurological sequelae attributable directly to prematurity. The objective of the present study is to describe maternal and perinatal complications in pregnant women with UTI caused by Escherichia coli and to find out the antimicrobial susceptibility pattern. METHODS: A descriptive and longitudinal study of pregnant women admitted to the Women's Hospital in Culiacan, Sinaloa, Mexico, was carried out from January 2013 to December 2014. Patients with E. coli infection were included, and infections caused by other microorganisms were excluded. The sociodemographic variables, causes of hospitalization and the type of maternal and perinatal complications were determined. RESULTS: The causes of admission to the hospital were threatened preterm labor, and fever and threatened abortion. Of 38 patients with threatened preterm labor, 33 went on to delivery, four were preterm births and two were neonatal deaths. E. coli was sensitive to over 90% of piperacillin-tazobactam, amikacin, nitrofurantoin and carbapenems. CONCLUSION: According to this study in a Mexican population, the number one admission diagnosis in women with UTI due to E. coli was threatened preterm labor, and fever and threatened abortion. E. coli was sensitive to more than 90% of piperacillin-tazobactam, amikacin, nitrofurantoin and carbapenems.

Effects of shiga toxin 2 on cellular regeneration mechanisms in primary and three-dimensional cultures of human renal tubular epithelial cells.

Shiga toxin (Stx)-producing Escherichia coli (STEC) causes post-diarrheal Hemolytic Uremic Syndrome (HUS), which is one of the most common causes of acute renal failure in children in Argentine. The aim of the present work was to study the effects of Shiga toxin type 2 (Stx2) on regenerative mechanisms of primary cultures of human cortical renal tubular epithelial cells (HRTEC) and three-dimensional (3D) cultures of HRTEC. Primary cultures of HRTEC were able to develop tubular structures when grown in matrigel, which showed epithelial cells surrounding a central lumen resembling the original renal tubules. Exposure to Stx2 inhibited tubulogenesis in 3D-HRTEC cultures. Moreover, a significant increase in apoptosis, and decrease in cell proliferation was observed in tubular structures of 3D-HRTEC exposed to Stx2. A significant reduction in cell migration and vimentin expression levels was observed in HRTEC primary cultures exposed to Stx2, demonstrating that the holotoxin affected HRTEC dedifferentiation. Furthermore, a decreased number of cells expressing CD133 progenitor marker was found in HRTEC cultures treated with Stx2. The CD133 positive cells also expressed the Stx receptor globotriaosylceramide, which may explain their sensitivity to Stx2. In conclusion, Stx2 affects the regenerative processes of human renal tubular epithelial cells in vitro, by inhibiting cell dedifferentiation mechanisms, as well as tubules restoration. The development of 3D-HRTEC cultures that resemble original human renal proximal tubules is a novel in vitro model to study renal epithelial repair mechanisms after injury.

Defective renal dopamine function and sodium-sensitive hypertension in adult ovariectomized Wistar rats: role of the cytochrome P-450 pathway.

We have previously shown that ovariectomy in adult Wistar rats under normal sodium (NS) intake results in an overexpression of the total Na(+)-K(+)-ATPase (NKA) α1-subunit (Di Ciano LA, Azurmendi PJ, Toledo JE, Oddo EM, Zotta E, Ochoa F, Arrizurieta EE, Ibarra FR. Clin Exp Hypertens 35: 475-483, 2013). Upon high sodium (HS) intake, ovariectomized (oVx) rats developed defective NKA phosphorylation, a decrease in sodium excretion, and an increment in mean blood pressure (MBP). Since NKA phosphorylation is modulated by dopamine (DA), the aim of this study was to compare the intracellular response of the renal DA system leading to NKA phosphorylation upon sodium challenge in intact female (IF) and oVx rats. In IF rats, HS caused an increase in urinary DA and sodium, in NKA phosphorylation state, in cytochrome P-4504A (CYP4A) expression, and in 20-HETE production, while MBP kept normal. Blockade of the D1 receptor (D1R) with the D1-like receptor antagonist SCH 23390 in IFHS rats shifted NKA into a more dephosphorylated state, decreased sodium excretion by 50%, and increased MBP. In oVxNS rats, D1R expression was reduced and D3R expression was increased, and under HS intake sodium excretion was lower and MBP higher than in IFHS rats (both P < 0.05), NKA was more dephosphorylated than in IFHS, and CYP4A expression or 20-HETE production did not change. Blockade of D1R in oVxHS rats changed neither NKA phosphorylation state nor sodium excretion or MBP. D2R and PKCα expression did not vary among groups. The alteration of the renal DA system produced by ovariectomy could account for the defective NKA phosphorylation, the inefficient excretion of sodium load, and the development of salt-sensitive hypertension.

The Role of Psychological Factors in Noncardiac Chest Pain of Esophageal Origin.

Background/Aims: Noncardiac chest pain (NCCP) of esophageal origin is a challenging clinical problem of diverse etiology that affects more than 80 million Americans yearly. We assess the prevalence and impact of psychological disorders on NCCP of esophageal origin, describe possible mechanisms associated with this condition, and review psychological therapy options. Methods: Online search using PubMed and Medline from January 1, 1966, to April 30, 2023. Results: Psychological disorders have been reported in up to 79% of patients with NCCP of esophageal origin. Several psychological disturbances have been identified with this condition, including depression, anxiety, panic disorder, phobias, and obsessive-compulsive and somatoform disorders. It is unclear whether the psychological disorders trigger the chest pain or vice versa. Multiple psychological mechanisms have been linked to chest pain and may contribute to its pathogenesis and severity. These mechanisms include cardiophobia, poor coping strategies, negative social problem solving, stress and perceived control, hypervigilance to cardiopulmonary sensations, altered pain perception, and alexithymia. Psychological therapies for NCCP of esophageal origin include cognitive behavioral therapy, hypnotherapy, physical and relaxation training, breathing retraining, and alternative medicine. Among the therapeutic options, cognitive behavioral therapy has been shown to be an effective treatment for NCCP of esophageal origin. Conclusion: This review raises awareness about the high prevalence of psychological disorders in NCCP of esophageal origin and highlights the need for clinical trials and trained therapists to address the management of this taxing clinical problem.

Ovariectomy causes overexpression of renal Na(+),K(+)-ATPase and sodium-sensitive hypertension in adult Wistar rats.

We investigated the effect of ovariectomy(oVx) on renal and systemic hemodynamic, electrolyte excretion and total and dephosphorylated Na(+),K(+)-ATPase α1 subunit (t-d-NKA) in normotensive Wistar rats under a normal sodium (NS, 0.24%) or high sodium (HS, 1%) intake versus intact female (IF). On NS intake, t-d-NKA was higher in oVx rats and overexpressed in the thick ascending limbs (P < .01 vs. IF) and renal plasma flow was increased. On HS intake, oVx rats maintained a greater dephosphorylated NKA, excreted less sodium, and developed arterial hypertension (134 ± 4 vs. IF 112 ± 5 mm Hg, P < .05). Sodium load caused salt-sensitive hypertension in oVx Wistar rats.

Binding of losartan to angiotensin AT1 receptors increases dopamine D1 receptor activation.

Signaling through both angiotensin AT1 receptors (AT1R) and dopamine D1 receptors (D1R) modulates renal sodium excretion and arterial BP. AT1R and D1R form heterodimers, but whether treatment with AT1R antagonists functionally modifies D1R via allosterism is unknown. In this study, the AT1R antagonist losartan strengthened the interaction between AT1R and D1R and increased expression of D1R on the plasma membrane in vitro. In rat proximal tubule cells that express endogenous AT1R and D1R, losartan increased cAMP generation. Losartan increased cAMP in HEK 293a cells transfected with both AT1R and D1R, but it did not increase cAMP in cells transfected with either receptor alone, suggesting that losartan induces D1R activation. Furthermore, losartan did not increase cAMP in HEK 293a cells expressing AT1R and mutant S397/S398A D1R, which disrupts the physical interaction between AT1R and D1R. In vivo, administration of a D1R antagonist significantly attenuated the antihypertensive effect of losartan in rats with renal hypertension. Taken together, these data imply that losartan might exert its antihypertensive effect both by inhibiting AT1R signaling and by enhancing D1R signaling.

Sexual hormones modulate compensatory renal growth and function.

The role played by sexual hormones and vasoactive substances in the compensatory renal growth (CRG) that follows uninephrectomy (uNx) is still controversial. Intact and gonadectomized adult Wistar rats of both sexes, with and without uNx, performed at 90 days age, were studied at age 150 days. Daily urine volume, electrolyte excretion and kallikrein activity (UKa) were determined. Afterwards, glomerular filtration rate and blood pressure were measured, the kidneys weighed and DNA, protein and RNA studied to determine nuclei content and cell size. When the remnant kidney weight at age 150 days was compared with the weight of the kidney removed at the time of uNx, male uNx rats showed the greatest CRG (50%) while growth in the other uNx groups was 25%, 15% and 19% in orchidectomized, female and ovariectomized rats, respectively. The small CRG observed in the uNx female rats was accompanied by the lowest glomerular filtration value, 0.56 ± 0.02 ml/ min/g kwt compared, with the other uNx groups, p < 0.05. Cell size (protein or RNA/DNA) was similar for all the groups except for uNx orchidectomized rats. In this group the cytoplasmatic protein or RNA content was lower than in the other groups while DNA (nuclei content) was similar. Some degree of hyperplasia was determined by DNA content in the uNx groups. Male sexual hormones positively influenced CRG and its absence modulated cell size. Female sexual hormones, instead, did not appear to stimulate CRG. The kallikrein kinin system may not be involved in CRG.

Behavior of the renal kallikrein in spontaneously hypertensive rats: Influence of sexual hormones and aldosterone-sensitive distal nephron ion channels.

The renal kallikrein-kinin system (RKKS) has been related to blood pressure control and sodium and water balance. We have previously shown that female spontaneously hypertensive rats (SHR) have high urinary kallikrein activity (UKa) and lower blood pressure (BP) than males whereas ovariectomy stimulates UKa and diminishes BP. We also showed that high K+ intake and prepuberal gonadectomy (Gx) diminish BP with a concomitant increase in UKa and plasma aldosterone levels. Since kallikrein co-localize in the same distal nephron segments of aldosterone effectors, we explored the effect of pharmacological blockage of aldosterone receptor, epithelial Na+ (ENaC) and the rectifying outer medulla K+ (ROMK) channels in different gonad contexts on the gene expression, renal tissue content and urine release of kallikrein. Klk1 gene expression was determined by real-time PCR and enzymatic activity of kallikrein by the amidolytic method. We found that the inhibition of the aldosterone receptor by spironolactone increases kallikrein renal tissue storage and decreases its urinary activity, especially in Gx rats. Moreover, ENaC blockade by benzamil increases the renal content of kallikrein without affecting synthesis or excretion, especially in females and Gx animals, while the inhibition of ROMK by glibenclamide increases the synthesis and renal content of kallikrein only in intact male animals. We concluded that RKKS regulation showed sexual dimorphism and seemed to be modulated by sex hormones throughout a process involving aldosterone and the aldosterone-sensitive ion channels..

Prolactin and dopamine 1-like receptor interaction in renal proximal tubular cells.

Prolactin is a natriuretic hormone and acts by inhibiting the activity of renal tubular Na(+)-K(+)-ATPase activity. These effects require an intact renal dopamine system. Here, we have studied by which mechanism prolactin and dopamine interact in Sprague-Dawley rat renal tissue. Na(+)-K(+)-ATPase activity was measured as ouabain-sensitive ATP hydrolysis in microdissected renal proximal tubular segments. Intracellular signaling pathways were studied by a variety of different techniques, including Western blotting using phosphospecific antibodies, immunoprecipitation, and biotinylation assays. We found that dopamine and prolactin regulated Na(+)-K(+)-ATPase activity via similar signaling pathways, including protein kinase A, protein kinase C, and phosphoinositide 3-kinase activation. The cross talk between prolactin and dopamine 1-like receptors was explained by a heterologous recruitment of dopamine 1-like receptors to the plasma membrane in renal proximal tubular cells. Prolactin had no effect on Na(+)-K(+)-ATPase activity in spontaneously hypertensive rats, a rat strain with a blunted response to dopamine. These results further emphasize the central role of the renal dopamine system in the interactive regulation of renal tubular salt balance.

Patterns of renal dopamine release to regulate diuresis and natriuresis during volume expansion. Role of renal monoamine-oxidase.

Diuretic and natriuretic effects of renal dopamine (DA) are well established. However, in volume expansion the pattern of renal DA release into urine (UDAV) and the role of enzymes involved in DA synthesis/degradation have not yet been defined. The objective was to determine the pattern of UDAV during volume expansion and to characterize the involvement of monoamine-oxidase (MAO) and aromatic amino-acid decarboxylase (AADC) in this response. In this study male Wistar rats were expanded with NaCl 0.9% at a rate of 5% BWt per hour. At the beginning of expansion three groups received a single drug injection as follows: C (vehicle, Control), IMAO (MAO inhibitor Pargyline, 20 mg/kg BWt, i.v.) and BNZ (AADC inhibitor Benserazide, 25 mg/kg BWt, i.v.). Results revealed that in C rats UDAV (ng/30 min/100g BWt) increased in the first 30 min expansion from 11.5 +/- 1.20 to 21.8 +/- 3.10 (p < 0.05) and decreased thereafter. IMAO showed a similar pattern but significantly higher than C at 30 min expansion (32.5 +/- 2.20, p < 0.05). IMAO greatly reduced MAO activity from 8.29 +/- 0.35 to 1.1 +/- 0.03 nmol/mg tissue/hour and significantly increased diuresis and natriuresis over controls. BNZ abolished the early UDAV peak to 3.2+/-0.72 (p < 0.01) and though, UDAV increased over C after 60 min expansion, natriuresis and diuresis were diminished by BNZ treatment. Results indicate that an increment in renal DA release into urine occurs early in expansion and in a peak-shaped way. In this response MAO plays a predominant role.

[Female hormones in renal physiology. Salt sensitivity and regulation of epithelial proliferation]. / Las hormonas femeninas en fisiología renal. Sensibilidad a la sal y regulación de la proliferación epitelial.

Female sex hormones participate in the regulation of blood pressure and renal epithelial proliferation, effects not related to their reproductive function. About one-third of the world's population has abnormally high levels of blood pressure, hypertension, which is responsible for almost 50% of deaths from stroke and coronary heart disease. Salt sensitivity is a risk factor for cardiovascular morbidity and mortality and other diseases as well. We reported a model of salt sensitive hypertension in adult ovariectomized (oVx) Wistar rats. oVx rats are normotensive under normal salt intake (NS, 0.24% NaCl), but upon a high salt intake (HS, 1% NaCl) oVx rats developed a blood pressure profile of salt-sensitive hypertension. Our studies on kidney molecules related to sodium balance found that the circuit dopamine D1-like receptor, cytochrome P450 4A and Na+, K+-ATPase is altered by the absence of ovary hormones which is accompanied by a reduced ability to excrete sodium. In oVx rats HS intake also promotes changes in the expression of proteins related to sodium transport in peripheral blood mononuclear cells, mainly peripheral lymphocytes. Therefore, sodium transport is modified at several levels of normal physiology. Lately, we described that estradiol increases the rate of renal epithelial cell proliferation in primary cultures developed from human renal cortex. Thus, salt sensitivity, adaptive immunity, blood pressure and renal cell proliferation are complex biological responses regulated by female sex hormones.

Un tercio de la población mundial tiene niveles anormalmente altos de presión arterial, hipertensión, responsable de casi el 50% de las muertes por accidente cerebrovascular y enfermedad coronaria. La sensibilidad a la sal es un factor de riesgo para la morbilidad y mortalidad cardiovascular y también para otras enfermedades. En estudios previos describimos un modelo de hipertensión sal sensible (HSS) en ratas Wistar ovariectomizadas (oVx) adultas. Las ratas oVx son normotensas con ingesta normal de sal (NS, 0.24% de NaCl), pero desarrollan un perfil de HSS con una ingesta elevada de sal (HS, 1% de NaCl). En los estudios en riñón encontramos que el circuito receptor D1 de dopamina, citocromo P450 4A y Na+, K+-ATPasa está alterado por la ausencia de hormonas ováricas, lo que se asocia a menor excreción de sodio e hipertensión arterial. La ingesta HS en ratas oVx también promueve cambios en la expresión de proteínas relacionadas con el transporte de sodio en células mononucleares de sangre periférica, principalmente linfocitos periféricos. Por lo tanto, el transporte de sodio se modifica en varios niveles de la fisiología normal. En estudios recientes observamos que el estradiol aumenta la proliferación y diferenciación de células epiteliales en cultivos de corteza renal humana. Sensibilidad a la sal, inmunidad adaptativa, presión arterial y proliferación de células epiteliales en riñón son fenómenos de gran importancia biológica regulados por estradiol.

Gonadectomy influences blood pressure through the kallikrein-kinin system.

The kallikrein-kinin system (KKS) appears to be involved in blood pressure regulation. We showed that ovariectomy (oVx) stimulates urinary kallikrein activity (UKa). So, we test whether gonadectomy (Gx) would affect blood pressure through an increase in KKS activity and which mechanism(s) were involved. We studied adult Wistar rats of either sex, with and without Gx. At baseline all groups were normotensive although the oVx mean arterial pressure (MAP) was lower than female MAP (p < 0.05). KKS blockade by aprotinin increased MAP (p < 0.05) exclusively in the oVx group. The probably mechanism(s) involved in KKS regulation (synthesis, renal content and UKa) were also studied. Previous Gx, kallikrein content (nkat/g kidney weight) and UKa (nkat/g kidney weight/day) were higher in female than in male rats: 12 +/- 1.1 versus 6 +/- 0.7 and 40 +/- 6.8 versus 26 +/- 3.4, respectively. After Gx, kallikrein content increased significantly in both orchiectomized (oRx) and oVx rats, and UKa showed a similar tendency (NS). Kallikrein synthesis did not show gender difference in non-Gx rats, but an increase after oVx was observed. KKS was found to be involved in blood pressure regulation in oVx animals. oVx may trigger the increase in kallikrein synthesis and content and UKa to act upon blood pressure.

Urinary kallikrein and blood pressure--gender-different response to potassium supplementation in SHR. Role of aldosterone.

AIMS: To test whether blood pressure is affected by potassium supplementation which modifies urinary kallikrein (UK) in SHR of either sex, and to elucidate the mechanisms involved. DESIGN: In SHR and WKY blood pressure, renal function and hormonal profile were studied after 1% oral potassium supplementation starting at 4 weeks of age and throughout until 12 weeks of age. Results were compared with those of untreated SHR and WKY of either sex. RESULTS: Systolic blood pressure (mm Hg) started to rise in SHR and was significantly different at 6-8 weeks of age: 153.5 +/- 7.9 versus 100 +/- 5.6 in female and 157 +/- 7.7 versus 98.4 +/- 6.8 in male rats (p < 0.01). Systolic blood pressure increased progressively in female and male rats reaching 164.5 +/- 4.8 and 204.5 +/- 7.6, respectively, at 12 weeks of age. At this time systolic blood pressure was higher in male than in female SHR (p < 0.01) and UK activity (UKa; nkat/day/100 g body weight) was slightly lower in male SHR. After 1% oral potassium supplementation administered from 4 to 12 weeks of age, a decrease in systolic blood pressure was seen in male SHR: 204.5 +/- 7.6 versus 173.5 +/- 7.9 (p < 0.05); and 164.5 +/- 4.8 versus 156.8 +/- 5.5 in female rats (NS) at 12 weeks of age, concomitant with an increase in UKa, particularly in male rats (29.35 +/- 1.92 versus 36.54 +/- 2.61, p < 0.05). As expected, plasma aldosterone (pg/ml), increased markedly after potassium treatment from 129 +/- 31.4 in untreated female and male SHR and WKY to 528 +/- 180.7 in SHR and 473 +/- 88.4 in WKY (p < 0.05 in both cases). After potassium supplementation, potassium excretion was significantly correlated with both aldosterone levels and UKa (p < 0.001 in both cases). No significantly concurrent changes in plasma renin activity were observed, but instead a significant decrease was seen in SHR (p < 0.01). The potassium blood pressure-lowering effect was blunted by aldosterone receptor antagonist treatment that also decreased UKa from 36.5 +/- 2.61 to 19.5 +/- 1.9, particularly in male SHR. No attempt was made in this experimental setting to block kallikrein or kinin receptors. CONCLUSIONS: UKa increases as a consequence of aldosterone stimulation by potassium load since an aldosterone receptor blockade abolishes UKa increment and blood pressure fall. These results further support the hypothesis that the kallikrein kinin system plays a role in blood pressure regulation and they also show a gender different response to potassium load in relation to UKa and blood pressure.

Mechanisms of PKC-dependent Na+ K+ ATPase phosphorylation in the rat kidney with chronic renal failure.

The present work was designed to study Na+ K+ ATPase alpha1-subunit phosphorylation in rats with chronic renal failure (CRF) in comparison with normal rats. Na+ K+ ATPase alpha1-subunit phosphorylation degree was measured by binding the McK-1 antibody to dephosphorylated Ser-23 in microdissected medullary thick ascending limb of Henle (mTAL) segments. In addition, the total Na+ K+ ATPase alpha1-subunit expression and activity were also measured in the outer renal medulla homogenates and membranes. CRF rats showed a higher Na+ K+ ATPase activity, as compared with control rats (18.95 +/- 2.4 vs. 11.21 +/- 1.5 micromol Pi/mg prot/h, p < 0.05), accompanied by a higher total Na+ K+ ATPase expression (0.54 +/- 0.04 vs. 0.27 +/- 0.02 normalized arbitrary units (NU), p < 0.05). When McK-1 antibody was used, a higher immunosignal in mTAL of CRF rats was observed, as compared with controls (6.3 +/- 0.35 vs. 4.1 +/- 0.33 NU, p < 0.05). The ratio Na+ K+ ATPase alpha1-subunit phosphorylation/total Na+ K+ ATPase alpha1-subunit expression per microg protein showed a non-significant difference between CRF and control rats in microdissected mTAL segments (2.11 +/- 0.12 vs. 2.26 +/- 0.18 NU, p = NS). The PKC inhibitor RO-318220 10(-6) M increased immunosignal (lower phosphorylation degree) in mTAL of CRF rats to 128.43 +/- 7.08% (p < 0.05) but did not alter McK1 binding in control rats. Both phorbol 12-myristate 13-acetate (PMA) 10(-6) M and dopamine 10(-6) M decreased immunosignal in CRF rats, corresponding to a higher Na+ K+ ATPase alpha1-subunit phosphorylation degree at Ser-23 (55.26 +/- 11.17% and 53.27 +/- 7.12% compared with basal, p < 0.05). In mTAL of CRF rats, the calcineurin inhibitor FK-506 10(-6) M did not modify phosphorylation degree at Ser-23 of Na+ K+ ATPase alpha1-subunit (100.21 +/- 3.00% compared with basal CRF). In control rats, FK 506 10(-6) M decreased the immunosignal, which corresponds to a higher Na+ K+ ATPase alpha1-subunit phosphorylation degree at Ser-23. The data suggest that the regulation of basal Na+ K+ ATPase alpha1-subunit phosphorylation degree at Ser-23 in mTAL segments of CRF rats was primarily dependent on PKC activation rather than calcineurin dependent mechanisms.

Concerted regulation of renal plasma flow and glomerular filtration rate by renal dopamine and NOS I in rats on high salt intake.

Under high sodium intake renal dopamine (DA) increases while NOS I expression in macula densa cells (MD) decreases. To explore whether renal DA and NOS I, linked to natriuresis and to the stability of the tubuloglomerular feedback, respectively, act in concert to regulate renal plasma flow (RPF) and glomerular filtration rate (GFR). Male Wistar rats were studied under a normal sodium intake (NS, NaCl 0.24%) or a high sodium intake (HS, NaCl 1% in drinking water) during the 5 days of the study. For the last two days, the specific D1-like receptor antagonist SCH 23390 (1 mg kg bwt-1 day-1, sc) or a vehicle was administered. HS intake increased natriuresis, diuresis, and urinary DA while it decreased cortical NOS I expression (P < 0.05 vs. NS), Nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) activity in MD (P < 0.001 vs. NS) and cortical nitrates+nitrites (NOx) production (NS 2.04 ± 0.22 vs. HS 1.28 ± 0.10 nmol mg protein-1, P < 0.01). Treatment with SCH 23390 to rats on HS sharply decreased hydroelectrolyte excretion (P < 0.001 vs. HS) while NOS I expression, NADPH-d activity and NOx production increased (P < 0.05 vs. HS for NOS I and P < 0.001 vs. HS for NADPH-d and NOx). SCH 23390 increased RPF and GFR in HS rats (P < 0.01 HS+SCH vs. HS). It did not cause variations in NS rats. Results indicate that when NS intake is shifted to a prolonged high sodium intake, renal DA through the D1R, and NOS I in MD cells act in concert to regulate RPF and GFR to stabilize the delivery of NaCl to the distal nephron.

Maternal Risk Factors Associated with the Development of Cleft Lip and Cleft Palate in Mexico: A Case-Control Study.

INTRODUCTION: Cleft lip and palate, the most common developmental deformity, is seen worldwide and the etiology involves a combination of genetic and environmental factors. The purpose of this study was to determine the maternal risk factors associated with the development of cleft lip and cleft palate. MATERIALS AND METHODS: We conducted a case control study at the Women's Hospital in Culiacan, Mexico. Medical records were analyzed, including patients who delivered babies with and without cleft lip and cleft palate from January 2010 to December 2015. Multiple variables were analyzed, including gestational age, weight at birth, the use of folic acid and multivitamins during pregnancy, smoking, alcohol abuse, the use of recreational drugs, history of sexually transmitted infections, marital status, socioeconomic status, education, and nutritional status. RESULTS: We found that the maternal risk factors with the strongest association for the development of cleft lip and cleft palate were the following: patients who were not taking folic acid during pregnancy [OR 3.27, 95% CI 1.32-8.09], P=0.00; patients who were not taking vitamin supplementation during pregnancy [OR 2.6, 95% CI 1.19-7.27], P=0.02; smoking during pregnancy [OR 2.05, 95% CI 1.23-3.41], P=0.01; and alcohol abuse during pregnancy [OR 1.90, 95% CI 1.17-3.08], P=0.03. CONCLUSIONS: The main risk factors associated with the development of cleft lip and cleft palate in a Mexican population at the Women's hospital in Culiacan, Sinaloa, Mexico were smoking, alcohol abuse, and patients not taking folic acid and multivitamins during pregnancy.