Association study of the elastin microfibril interfacer 1 (EMILIN1) gene in essential hypertension

Extracellular Matrix Proteome Remodeling in Human Glioblastoma and Medulloblastoma

Medulloblastomas (MBs) and glioblastomas (GBMs) are high-incidence central nervous system tumors. Different origin sites and changes in the tissue microenvironment have been associated with the onset and progression. Here, we describe differences between the extracellular matrix (ECM) signatures of these tumors. We compared the proteomic profiles of MB and GBM decellularized tumor samples between each other and their normal decellularized brain site counterparts. Our analysis revealed that 19, 28, and 11 ECM proteins were differentially expressed in MBs, GBMs, and in both MBs and GBMs, respectively. Next, we validated key findings by using a protein tissue array with 53 MB and 55 GBM cases and evaluated the clinical relevance of the identified differentially expressed proteins through their analysis on publicly available datasets, 763 MB samples from the GSE50161 and GSE85217 studies, and 115 GBM samples from RNAseq-TCGA. We report a shift toward a denser fibrillary ECM as well as a clear alteration in the glycoprotein signature, which influences the tumor pathophysiology. MS data have been submitted to the PRIDE repository, project accession: PXD023350.

Phylogenic Determinants of Cardiovascular Frailty, Focus on Hemodynamics and Arterial Smooth Muscle Cells

The evolution of the circulatory system from invertebrates to mammals has involved the passage from an open system to a closed in-parallel system via a closed in-series system, accompanying the increasing complexity and efficiency of life’s biological functions. The archaic heart enables pulsatile motion waves of hemolymph in invertebrates, and the in-series circulation in fish occurs with only an endothelium, whereas mural smooth muscle cells appear later. The present review focuses on evolution of the circulatory system. In particular, we address how and why this evolution took place from a closed, flowing, longitudinal conductance at low pressure to a flowing, highly pressurized and bifurcating arterial compartment. However, although arterial pressure was the latest acquired hemodynamic variable, the general teleonomy of the evolution of species is the differentiation of individual organ function, supported by specific fueling allowing and favoring partial metabolic autonomy. This was achieved via the establishment of an active contractile tone in resistance arteries, which permitted the regulation of blood supply to specific organ activities via its localized function-dependent inhibition (active vasodilation). The global resistance to viscous blood flow is the peripheral increase in frictional forces caused by the tonic change in arterial and arteriolar radius, which backscatter as systemic arterial blood pressure. Consequently, the arterial pressure gradient from circulating blood to the adventitial interstitium generates the unidirectional outward radial advective conductance of plasma solutes across the wall of conductance arteries. This hemodynamic evolution was accompanied by important changes in arterial wall structure, supported by smooth muscle cell functional plasticity, including contractility, matrix synthesis and proliferation, endocytosis and phagocytosis, etc. These adaptive phenotypic shifts are due to epigenetic regulation, mainly related to mechanotransduction. These paradigms actively participate in cardio-arterial pathologies such as atheroma, valve disease, heart failure, aneurysms, hypertension, and physiological aging.

NG2 Glia: Novel Roles beyond Re-/Myelination

Neuron-glia antigen 2-expressing glial cells (NG2 glia) serve as oligodendrocyte progenitors during development and adulthood. However, recent studies have shown that these cells represent not only a transitional stage along the oligodendroglial lineage, but also constitute a specific cell type endowed with typical properties and functions. Namely, NG2 glia (or subsets of NG2 glia) establish physical and functional interactions with neurons and other central nervous system (CNS) cell types, that allow them to constantly monitor the surrounding neuropil. In addition to operating as sensors, NG2 glia have features that are expected for active modulators of neuronal activity, including the expression and release of a battery of neuromodulatory and neuroprotective factors. Consistently, cell ablation strategies targeting NG2 glia demonstrate that, beyond their role in myelination, these cells contribute to CNS homeostasis and development. In this review, we summarize and discuss the advancements achieved over recent years toward the understanding of such functions, and propose novel approaches for further investigations aimed at elucidating the multifaceted roles of NG2 glia.

Changes in extracellular matrix in subcutaneous small resistance arteries of patients with essential hypertension

BACKGROUND

In the development of hypertensive microvascular remodeling, a relevant role may be played by changes in extracellular matrix proteins. Aim of this study was the to evaluate some extracellular matrix components within the tunica media of subcutaneous small arteries in 9 normotensive subjects and 12 essential hypertensive patients, submitted to a biopsy of subcutaneous fat from the gluteal or the anterior abdominal region.

PATIENTS AND METHODS

Subcutaneous small resistance arteries were dissected and mounted on an isometric myograph, and the tunica media to internal lumen ratio was measured. In addition, fibronectin, laminin, transforming growth factor-beta-1 (TGF-β1) and emilin-1 contents within the tunica media were evaluated by immunofluorescence and relative immunomorphometrical analysis (immunopositivity % of area). The total collagen content and collagen subtypes within the tunica media were evaluated using both Sirius red staining (under polarized light) and immunofluorescence assay.

RESULTS

Normotensive controls had less total and type III collagen in respect with hypertensive patients. Fibronectin and TGF-β1 tunica media content was significantly greater in essential hypertensive patients, compared with normotensive controls, while laminin and emilin-1 tunica media content was lesser in essential hypertensive patients, compared with normotensive controls. A significant correlation was observed between fibronectin tunica media content and media to lumen ratio.

CONCLUSIONS

Our results indicate that, in small resistance arteries of patients with essential hypertension, a relevant fibrosis may be detected; fibronectin and TGF-β1 tunica media content is increased, while laminin and emilin-1 content is decreased; these changes might be involved in the development of small resistance artery remodeling in humans.

Detection of Pathological Changes in the Aorta during Thoracic Aortic Aneurysm Progression on Molecular Level

The progression of thoracic aortic aneurysm depends on regulation of aortic wall homeostasis and on changes in the structural components of the extracellular matrix, which are affected by multiple molecular signalling pathways. We decided to correlate the diameter of ascending thoracic aneurysm with gene expression of inflammation markers (IL-6, CRP), cytokine receptors (IL-6R, TNFR1, and TNFR2), and extracellular matrix components (Emilin-1, MMP9, and TIMP) for detection of the degree of pathological process of TAA formation. The experimental group was divided into three groups according to the diameter of the aortic aneurysm. Whole blood and tissue samples were properly collected and used for nucleic acid, chromatin, and protein isolation. The mRNA levels were detected by qRT-PCR. For the detection of protein levels a Cytokine Array IV assay kit was used in combination with a biochip analyzer. In aortic tissue, significant positive correlations were found between increased mRNA levels of inflammatory cytokines (CRP and IL-6) on both mRNA levels in tissue and protein from the blood with maximum in stage 3. Changes of gene expression of selected genes can be used for the experimental study of the inflammatory receptor inhibitors during trials targeted on slowing down the progress of aortic wall aneurysm.

Role of clathrin in dense core vesicle biogenesis

The dense core vesicles (DCVs) of neuroendocrine cells are a rich source of bioactive molecules such as peptides, hormones, and neurotransmitters, but relatively little is known about how they are formed. Using fractionation profiling, a method that combines subcellular fractionation with mass spectrometry, we identified ∼1200 proteins in PC12 cell vesicle-enriched fractions, with DCV-associated proteins showing distinct profiles from proteins associated with other types of vesicles. To investigate the role of clathrin in DCV biogenesis, we stably transduced PC12 cells with an inducible short hairpin RNA targeting clathrin heavy chain, resulting in ∼85% protein loss. DCVs could still be observed in the cells by electron microscopy, but mature profiles were approximately fourfold less abundant than in mock-treated cells. By quantitative mass spectrometry, DCV-associated proteins were found to be reduced approximately twofold in clathrin-depleted cells as a whole and approximately fivefold in vesicle-enriched fractions. Our combined data sets enabled us to identify new candidate DCV components. Secretion assays revealed that clathrin depletion causes a near-complete block in secretagogue-induced exocytosis. Taken together, our data indicate that clathrin has a function in DCV biogenesis beyond its established role in removing unwanted proteins from the immature vesicle.

Elastin microfibril interface-located protein 1, transforming growth factor beta, and implications on cardiovascular complications

Elastin microfibril interface-located protein 1 (EMILIN1), a glycoprotein, is associated with elastin in the extracellular matrix (ECM) of arteries, lymph vasculature, and other tissues. EMILIN1 particularly has a niche role in elastin fiber biogenesis (elastogenesis) by aiding with the fusion of elastin fibers, rendering them more ordered. In addition to elastogenesis, EMILIN1 has been shown to have roles in maintenance of vascular cell morphology, smooth muscle cell adhesion to elastic fibers, and transforming growth factor (TGFβ) regulation, by inhibiting TGFβ activation via blocking the proteolytic production of the latency-associated peptide/active TGFβ complex. The increased TGFβ signaling induced during EMILIN1 deficiency alters TGFβ activity, resulting in vascular smooth muscle cell growth and vascular remodeling. The increasing systemic blood pressure associated with TGFβ signaling may be closely linked to the activity of other mediators that affect cardiovascular homeostasis, such as angiotensin II. The increase in prevalence of hypertension and other cardiovascular diseases in other disease states likely involve a complex activation of TGFβ signaling and ECM dysfunction. Thus, the interaction of TGFβ and ECM components appears to be integrative involving both structural alterations to vessels through EMILIN1 and changes in TGFβ signaling processes. This review summarizes the current knowledge on the EMILIN1-TGFβ relationship; the specific roles of EMILIN1 and TGFβ in blood pressure regulation, their synergistic interaction, and in particular the role of TGFβ (in conjunction with ECM proteins) in other disease states altering cardiovascular homeostasis.

The crucial role of emilin 1 gene expression during progression of tumor growth

BACKGROUND

This study describes the effect of rapid tumor growth of patients suffering from various grades of malignant ductal breast carcinoma associated with the gene expression of ECM protein emilin 1, in correlation with the number of gene copies of emilin 1 and degradation of tumor tissue proteins.

METHODS

A total of 40 examined patients participated in the experiment (controls, n = 10, grades GI-GIII, each n = 10). After isolation of total mRNA, transcription of mRNA into the cDNA was performed. Quantification of gene expression changes was detected by the real-time PCR method. Analysis at the protein level was performed via Western blot method.

RESULTS

During the detection of changes at the mRNA level, a significantly decreased level of emilin 1 in tumor tissues with grade II (about 54 ± 8 % lower than control) was identified. Protein-level analysis indicated an increased level of emilin 1 in tumors with grade I in comparison with control samples (about 10 ± 3 %).

CONCLUSION

Obtained results demonstrated that the suppressive role of emilin 1 is related to the grade of growing breast tumors, and associated with increased hypoxia in the tumor microenvironment followed by elevated unfolding and degradation of tissue proteins.

Adrenal Clocks and the Role of Adrenal Hormones in the Regulation of Circadian Physiology

The mammalian circadian timing system consists of a master pacemaker in the suprachiasmatic nucleus (SCN) and subordinate clocks that disseminate time information to various central and peripheral tissues. While the function of the SCN in circadian rhythm regulation has been extensively studied, we still have limited understanding of how peripheral tissue clock function contributes to the regulation of physiological processes. The adrenal gland plays a special role in this context as adrenal hormones show strong circadian secretion rhythms affecting downstream physiological processes. At the same time, they have been shown to affect clock gene expression in various other tissues, thus mediating systemic entrainment to external zeitgebers and promoting internal circadian alignment. In this review, we discuss the function of circadian clocks in the adrenal gland, how they are reset by the SCN and may further relay time-of-day information to other tissues. Focusing on glucocorticoids, we conclude by outlining the impact of adrenal rhythm disruption on neuropsychiatric, metabolic, immune, and malignant disorders.

Common variants in TGFBR2 and miR-518 genes are associated with hypertension in the Chinese population

BACKGROUND

An animal study reported that TGF-β1 maturation was linked to the homeostasis of blood pressure and elastogenesis of essential hypertension (EH). Recent advances require further research of TGF-β1 receptor in EH.

METHODS

A case-control study comprised of 2,012 adult hypertension case patients and 2,210 adult control subjects was conducted, and the association with blood pressure was further tested in children. Logistic regression and calculated genetic risk score were used to evaluate the effects of one single nucleotide polymorphism (SNP) and multiple SNPs on EH, respectively.

RESULTS

The genetic risk score of 10 SNPs showed a significant association with hypertension; the odds ratio of the upper quartile vs. the lower quartile was 1.282 (P = 4.67 × 10(-3)). rs7256241 in miR-518 was significantly associated with diastolic blood pressure (DBP) change in control subjects (P = 0.002), and this association was also observed in children (P = 0.04). The systolic blood pressure (SBP) and DBP of female patients taking reserpine were higher with the C and G alleles of rs3773661 (P = 0.004) and rs7256241 (P = 0.002), respectively. In patients taking Zhen Ju Jiang Ya tablets, SBP and DBP decreased linearly with rs749794 (P = 0.004 and P = 0.048, respectively). SBP decreased linearly with rs1155705 (P = 0.007) and rs11709624 (P = 0.04), but increased with rs1036096 (P = 0.03) in male patients. In male patients taking Jiang Ya tablets, SBP increased linearly with rs11709624 (P = 0.007), DBP increased linearly with rs1155705 (P = 0.03) whereas decreased with rs7256241 (P = 0.04).

CONCLUSIONS

Our results suggest that TGFBR2 and miR-518 harbor variants that increase the risk of EH and affect blood pressure homeostasis as well as efficacy of antihypertensive agents.

Visual DNA detection and SNP genotyping using asymmetric PCR and split DNA enzymes

We describe a method to detect DNA sequences visually through a color change reaction using DNAzymes. We successfully applied the assay for the detection of Salmonella and Mycobacterium DNA, as well as for genotyping single base differences from within human genomic DNA samples. Our approach adopts a split probe targeting system, designed with G-rich sequences, which reassembles in the presence of target DNA, producing G-quadruplexes with catalytic activity. Asymmetric PCR is first performed to amplify the target region into single-stranded copies, with primer ratios tailored for optimum amplification. This is followed by direct addition of the visual probes, substrates, and reagents to produce a color change within 15 min should the desired target sequences be present. This approach hence offers a rapid readout, ease-of-use, and handling convenience, especially at the point-of-care.

Perturbations of mechanotransduction and aneurysm formation in heritable aortopathies

Thoracic aortic aneurysm and dissection in young and middle aged patients is increasingly recognised as due to genetic aortopathy. Mutations in multiple genes affecting proteins in the extracellular matrix, microfibrillar structure, the endothelium and cell signalling pathways have been associated with thoracic aortic disease. The TGFß signalling pathway appears to play a key role in mediating abnormal aortic growth and aneurysm formation. A challenge remains in understanding how the many different gene mutations can result in deranged TGFß signalling. This review examines the functional relationships between key structural and signalling proteins, with reference to the need for maintenance of homeostasis in mechanotransduction within the aortic wall. A mechanism, through which perturbations in mechanotransduction, arising from different gene mutations, results in altered TGFß signalling is described.

A haplotype of the GOSR2 gene is associated with essential hypertension in Japanese men

OBJECTIVES

The Golgi SNAP receptor complex member 2 (GOSR2) gene is a Golgi-associated soluble factor attachment receptor (SNARE) protein involved in intra-Golgi protein trafficking on chromosome 17q21, which is the hypertension linkage peak on the human chromosome. The aim of the present study was to assess the association between the human GOSR2 gene and essential hypertension (EH) using a haplotype-based case-control study.

METHODS

A total of 320 EH patients and 205 age-matched controls were genotyped for the five single-nucleotide polymorphisms (SNPs) used as genetic markers for the human GOSR2 gene (rs197932, rs3785889, rs197922, rs17608766, and rs16941382). Data were analyzed for three separate groups: the total subjects, men, and women.

RESULTS

The overall distribution of the haplotypes in men was significantly different between the EH patients and the control subjects (P=0.002). Additionally, the frequency of the T-A-G haplotype (rs197932-rs3785889-rs197922) for men was significantly higher in the EH patients than in the control subjects (P=0.049). After adjustment for the major risk factors, multiple logistic regression analysis also revealed that the frequency of men with the T-A-G haplotype (homozygous and heterozygous diplotypes) was significantly higher than that in men without the haplotype (OR=1.756, P=0.039).

CONCLUSIONS

The results of this study indicate that the T-A-G haplotype may be a useful genetic marker for EH in Japanese men.

Estrogen synthesis genes CYP19A1, HSD3B1, and HSD3B2 in hypertensive disorders of pregnancy

Hypertension in pregnancy is a multifactorial disorder caused by a complex combination of environmental factors and several predisposing genes. Since estrogen modulates placental vascular development, estrogen synthases are considered plausible candidate genes. The aim of this haplotype-based case-control study was to estimate whether polymorphisms of the maternal estrogen synthesis genes (CYP19A1, HSD3B1 and HSD3B2) are associated with preeclampsia (PE) and gestational hypertension (GH). To examine the genetic markers in 69 PE and 62 GH patients and in 155 age-matched, primiparous, healthy control subjects, genotyping of 5 SNPs for the CYP19A1 gene (rs1870049, rs936306, rs700518, rs700519, and rs4646), 3 SNPs for the HSD3B1 gene (rs3765945, rs6203, and rs1047303), and 2 SNPs for the HSD3B2 gene (rs2854964 and rs1819698) was performed. For rs700158 of CYP19A1, the frequencies of the AG+GG genotype and the G allele were significantly higher in PE as compared to controls (P = 0.037, P = 0.033, respectively). Logistic regression analyses indicated that the AG+GG genotype of rs700158 was a PE risk factor (odds ratio = 2.15, P = 0.026). In addition, the frequency of the G-G haplotype established by rs700518-rs4646 was also significantly higher for PE (P = 0.017). These data suggest that the estrogen synthesis gene, CYP19A1 is associated with PE in the Japanese population.

Lack of an association between TSC gene Arg904Gln polymorphisms and essential hypertension risk based on a meta-analysis

Although there have been several studies investigating a possible association between essential hypertension and TSC gene Arg904Gln polymorphisms, the results have been inconsistent. We conducted a meta-analysis of four case-control studies (one study in Europe and three studies in Asia), including 1811 essential hypertension cases and 1381 controls. The pooled results showed no significant associations between any of these polymorphisms and essential hypertension (allele Arg vs allele Gln: odds ratio (OR) = 0.94, 95% confidence interval (95%CI) = 0.70-1.27), additive genetic model (Arg/Arg vs Gln/Gln: OR = 0.98, 95%CI = 0.43-2.23), dominant genetic model (Arg/Arg + Arg/Gln vs Gln/ Gln: OR = 0.97, 95%CI = 0.43-2.21), and recessive genetic model (Arg/ Arg vs Arg/Gln + Gln/Gln: OR = 1.03, 95%CI = 0.45-2.35). Based on the results of our meta-analysis, we conclude that the TSC gene Arg904Gln polymorphism is not associated with essential hypertension risk.

A Hypertension Gene: Are We There Yet?

Cardiovascular diseases are the leading cause of death worldwide. Essential hypertension is a major risk factor for the development of other cardiovascular diseases and is caused by a combination of environmental and genetic factors, with up to 50% of blood pressure variance currently attributed to an individual's genetic makeup. By studying genes that cause monogenic forms of hypertension and pathways relevant to blood pressure control, a number of polymorphisms have been identified that increase an individual's risk of developing high blood pressure. We report on candidate gene association studies and genome-wide association studies that have been performed to date in the field of hypertension research. It is becoming clear that for the majority of people there is no single gene polymorphism that causes hypertension, but rather a number of common genetic variants, each having a small effect. Using pharmacogenomics to personalize the treatment of hypertension holds promise for achieving and sustaining normotensive pressures quickly, while minimizing the risk of adverse reactions and unwanted side-effects. This will decrease the risk of stroke and myocardial infarction in individuals and lead to a reduced burden of disease upon society as a whole.

Pooled analyses of the associations of polymorphisms in the GRK4 and EMILIN1 genes with hypertension risk

BACKGROUND

The GRK4 and EMILIN1 genes have been suggested to be involved in the development of hypertension. However, the results have been inconsistent. In this study, a meta-analysis was performed to clarify the associations of polymorphisms in the GRK4 and EMILIN1 genes with hypertension risk.

METHODS

Published literature from PubMed and Embase databases were retrieved. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using fixed- or random-effects model.

RESULTS

Five studies for polymorphisms in the GRK4 gene and five studies for polymorphisms in the EMILIN1 gene were identified. The results suggested that rs1801058 polymorphism in the GRK4 gene was inversely associated with hypertension among East Asians (TT vs. CC: OR=0.39, 95%CI 0.28-0.55) and positively associated with hypertension among Europeans (TT vs. CC: OR= 2.38, 95%CI 1.38-4.10). Rs2960306 polymorphism in the GRK4 gene was significantly associated with hypertension among Europeans (TT vs. GG: OR=1.92, 95%CI 1.13-3.27). The significant associations were also observed for rs2011616 and rs2304682 polymorphisms in the EMILIN1 gene among Japanese (rs2011616: AA vs. GG: OR=0.38, 95%CI 0.18-0.82; rs2304682: GG vs. CC: OR=0.37, 95%CI 0.17-0.81) but not among Chinese.

CONCLUSIONS

This meta-analysis suggested that rs1801058 polymorphism in the GRK4 gene was associated with hypertension in East Asians and Europeans. The significant association was also found for rs2960306 polymorphism in the GRK4 gene among Europeans. In addition, there were significant associations of rs2011616 and rs2304682 polymorphisms in the EMILIN1 gene with hypertension among Japanese.

Association of intronic single-nucleotide polymorphisms in the EMILIN1 gene with essential hypertension in a Chinese population

Studies in mice suggest that the elastin microfibril interfacer-1 gene (EMILIN1), the gene encoding elastin microfibril interfacer-1 protein, contributes to the pathogenesis of essential hypertension (EH) in humans. EMILIN1 in part maintains elastic fibres in vessel walls, and hence peripheral arterial compliance. In a case-control study, we assessed 942 non-obese non-diabetic Chinese, comprising 467 patients with EH and 475 normotensive control subjects (166 without, and 309 with, family history of hypertension in first-degree relatives (FHH)). Hypertension in first-degree relatives occurred in 88%, 65% and 0% of cases, all controls and controls without FHH, respectively. We scanned for single-nucleotide polymorphisms (SNPs) and genotyped them in the EMILIN1 gene using high-resolution melt-curve analysis. No exonic variants were detected. We assessed the association of SNPs and their haplotypes with EH. Three SNPs in introns 1 and 5 (rs2289360, rs2011616 and rs7424556) were in strong pair-wise linkage disequilibrium (r(2)>0.89). All three SNPs were significantly associated with hypertension. Genotypic frequencies at the three SNPs differed significantly between cases and only those controls without FHH. Healthy controls with FHH should be excluded to increase the odds of detecting association. All the G alleles of rs2289360 (odds ratio = 1.69, P = 0.010), rs2011616 (odds ratio = 1.52, P = 0.038) and rs7424556 (odds ratio = 1.59, P = 0.023) were high-risk alleles in the recessive genetic model. We observed significant overall haplotypic association with EH (empirical P = 0.0072); GGG is a risk haplotype (P = 0.043). The overall results support EMILIN1 as a candidate gene for human EH.

Association of HSD3B1 and HSD3B2 gene polymorphisms with essential hypertension, aldosterone level, and left ventricular structure

BACKGROUND

HSD3B1 and HSD3B2 are crucial enzymes for the synthesis of hormonal steroids, including aldosterone. Therefore, HSD3B gene variations could possibly influence blood pressure (BP) by affecting the aldosterone level.

METHODS

We performed a haplotype- and diplotype-based case-control study to investigate the association between the HSD3B gene variations and essential hypertension (EH), aldosterone level, and left ventricular hypertrophy (LVH). A total of 275 EH patients and 286 controls were genotyped for four SNPs of the HSD3B1 gene (rs3765945, rs3088283, rs6203, and rs1047303) and for two SNPs of the HSD3B2 gene (rs2854964 and rs1819698). Aldosterone and LVH were investigated in 240 and 110 subjects respectively.

RESULTS

Significant differences were noted for the total and the male subject groups for the recessive model (CC versus TC+TT) of rs6203 between the controls and EH patients (P=0.030 and P=0.008 respectively). The frequency of the T-C haplotype established by rs3088283-rs1047303 was significantly higher for EH patients compared with the controls (P=0.014). Even though the polymorphism of HSB3B1 was not associated with LVH, the diplotype established by rs3088283-rs1047303 in the total subject group, along with the systolic BP, diastolic BP, and aldosterone level were significantly higher for those subjects who had the T-C haplotype versus those who did not (P=0.025, P=0.014, and P=0.006 respectively).

CONCLUSION

rs6203 and rs1047303 in the HSD3B1 gene are useful genetic markers for EH, while polymorphisms of HSD3B1 are associated with the BP and aldosterone level.