scholarly journals The functional state of the kallikrein-kinin and renin-angiotensin-aldosterone systems in patients with localized kidney cancer

2021 ◽  
Vol 9 (4) ◽  
pp. 101-110
Author(s):  
N. D. Ushakova ◽  
E. M. Frantsiyants ◽  
D. A. Rozenko ◽  
N. N. Popova ◽  
E. A. Marykov ◽  
...  

Introduction. The development of a malignant tumor naturally affects renal function. During tumor formation, the renal tissue is destructed either by direct invasion into the parenchyma, or by mechanical change in the renal architecture caused by compression of the renal parenchyma, collecting ducts, tubules, and nephrons. In addition, a tumor can secrete biologically active substances, which have an indirect negative influence the functional state of the organ. Currently, it has been established that kallikrein-kinin and renin-angiotensin-aldosterone systems play an important role in the development of nephropathy of various genesis. At the same time, these systems' role in the development of renal function disorders in the setting of tumor damage has not yet been studied.Purpose of the study. To study changes in the components of the kallikrein-kinin and renin-angiotensin-aldosterone systems in the case of localized kidney cancer.Materials and methods. Forty-five patients diagnosed with T1N0M0 kidney cancer and 13 relatively healthy patients without cancer were examined. The determination of the components of the systems under study was carried out by the kinetic method after chromatography of blood plasma and urine using DEAE-Sephadex A-50 (Amersham Biosciences Corp., Sweden). The indices of angiotensin-1, renin, aldosterone, and cortisol were studied by an indirect method of radioimmunoassay. Statistical processing was carried out using Statistica 8.0 software (StatSoft Inc., IBM Corp., USA) by means of the Student-Fisher test (p < 0.05).Results. The development of kidney cancer is accompanied by a 2.3-fold increase in the activity of kallikrein and other trypsin proteases with a significant deficiency of their inhibitors (p < 0,05). Against this background, there is a 1.3-fold decrease in the cortisol/renin ratio from a 2.9-fold and 2.3-fold increase in the values of the renin/angiotensin-I and cortisol/angiotensin-I interaction ratios, respectively, compared with the normal values of these indicators (p < 0,05).Conclusions. Renal cell carcinoma is accompanied by trespassing of local metabolism with the formation of tubulointerstitial dysfunction and a shift of the proteinase-inhibitory balance towards proteolytic activation.

2011 ◽  
Vol 167 (2) ◽  
pp. e63-e69 ◽  
Author(s):  
Viachaslau Barodka ◽  
Scott Silvestry ◽  
Ning Zhao ◽  
Xiangyin Jiao ◽  
David J. Whellan ◽  
...  

1980 ◽  
Vol 93 (3) ◽  
pp. 287-293 ◽  
Author(s):  
E. Jean Wickings ◽  
E. Nieschlag

Abstract. Adult male rhesus monkeys are aggressive animals and very difficult to handle. Hence experimental manipulations necessarily involve the use of restraint procedures, either chemical or physical, which may influence endocrine functions. Therefore, the effects of ketamine anaesthesia on basal hormone levels and on the pituitary response to LRH and TRH were investigated in 4 adult male rhesus monkeys. Values were compared to those obtained from the same animals restrained in primate chairs for approximately 48 h, a procedure to which they had been accustomed to over the preceding 6 months. Serum cortisol levels under anaesthesia were at all times lower than in conscious monkeys, but increased after 2 h to values twice as high as measured initially. Serum testosterone concentrations were not significantly different on the two occasions, but levels under anaesthesia were slightly higher initially than in the conscious monkeys, and decreased gradually over the 3 h test period. Initial prolactin levels were lower in the anaesthetized monkeys, and increased 2–3-fold after 90 min; values at 3 h were not significantly different from those in conscious monkeys. Intravenous TRH elicited a similar response in prolactin on both occasions, maximum values occurring after 15–30 min and returning to basal levels after 3 h. The maximum values attained and the area under the response curves were higher under anaesthesia. LRH stimulation resulted in a 15- and 30-fold increase in serum levels of biologically active LH, with and without anaesthesia, respectively. Basal levels were not significantly different on the two occasions. The area under the LH response curve was higher in 3 of the 4 monkeys without anaesthesia. The extent to which results in conscious monkeys are affected by stress is difficult to assess. Since neither handling technique allows for the collection of 'true' basal data, it is paramount to standardize and define the conditions under which experiments, and even routine blood sampling, are performed in male rhesus monkeys.


Endocrinology ◽  
2007 ◽  
Vol 148 (5) ◽  
pp. 2453-2457 ◽  
Author(s):  
Shigeyuki Wakahara ◽  
Tadashi Konoshita ◽  
Shinichi Mizuno ◽  
Makoto Motomura ◽  
Chikako Aoyama ◽  
...  

Angiotensin-converting enzyme (ACE) 2, a newly emerging component of the renin-angiotensin system, is presumed to be a counterregulator against ACE in generating and degrading angiotensin II. It remains to be elucidated how mRNA levels of these two genes are quantitatively regulated in the kidney and also what kind of clinicopathological characteristics could influence the gene expressions in humans. Seventy-eight cases of biopsy-proven renal conditions were examined in detail. Total RNA from a small part of each renal cortical biopsy specimen was reverse transcribed, and the resultant cDNA was amplified for ACE, ACE2, and glyceraldehyde-3-phosphate dehydrogenase with a real-time PCR system. Then we investigated the relationship between clinicopathological variables and mRNA levels adjusted for glyceraldehyde-3-phosphate dehydrogenase. Statistically significant correlation was not observed between any clinicopathological variables and either of the gene expressions by pairwise comparison. However, a strong correlation was observed between the gene expressions of ACE and those of ACE2. Moreover, the ACE to ACE2 ratio was significantly higher in subjects with hypertension (HT) than that in subjects without HT. Whereas parameters of renal function, e.g. urinary protein excretion (UPE) and creatinine clearance (Ccr), are not significantly related to the ACE to ACE2 ratio as a whole, the HT status may reflect disease-induced deterioration of renal function. That is, UPE and Ccr of subjects with HT are significantly different from those without HT, in which a significant correlation is also observed between UPE and Ccr. Finally, stepwise regression analysis further revealed that only the HT status is an independent confounding determinant of the ACE to ACE2 ratio among the variables tested. Our data suggest that ACE2 might play an important role in maintaining a balanced status of local renin-angiotensin system synergistically with ACE by counterregulatory effects confounded by the presence of hypertension. Thus, ACE2 may exert pivotal effects on cardiovascular and renal conditions.


2013 ◽  
Vol 4 (3) ◽  
Author(s):  
Renny M. Toreh ◽  
Sonny J.R. Kalangi ◽  
Sunny Wangko

Abstract: As the main structural component of the renin-angiotensin-aldosterone system (RAAS), the juxtaglomerular complex plays a very important role in the regulation of vascular resistance. The synthesis and release of renin into the circulation occurs due to the decrease of blood pressure, loss of body fluid, and a decrease of sodium intake. Renin converts angiotensinogen into angiotensin I, which is further converted by the angiotensin converting enzyme (ACE) into angiotensin II. This angiotensin II causes vasoconstriction of blood vessels, resulting in an increase of vascular resistance and blood pressure. The ACE inhibitors and the angiotensin receptor blockers (ARBs) do not inhibit the RAAS completely since they cause an increase of renin activity. The renin blockers are more effective in inhibiting RAAS activity; therefore, these renin blockers can be applied as antihypertensive agents with fewer side effects. The RAAS activity can be inhibited by a decrease of renin synthesis in the juxtaglomerular complex by blocking the signals in the juxtaglomerular complex that stimulate renin synthesis, and by blocking the gap junctions in the juxtaglomerular complex. Keywords: juxtaglomerular complex, vascular resistance, RAAS.   Abstrak: Kompleks jukstaglomerulus sebagai komponen struktural utama sistem renin angiotensin berperan penting dalam pengaturan resistensi pembuluh darah. Sintesis dan pelepasan renin ke sirkulasi terjadi karena tekanan darah yang rendah, kehilangan cairan tubuh, dan kurangnya intake natrium. Renin akan memecah angiotensinogen menjadi angiotesin I yang kemudian secara cepat dikonversi oleh enzim pengonversi angiotensin  menjadi angiotensin II. Angiotensin II menyebabkan vasokontriksi pembuluh darah sehingga meningkatkan resistensi pembuluh darah yang pada akhirnya akan meningkatkan tekanan darah. ACEinhibitor dan ARB kurang sempurna dalam menghambat kerja SRAA oleh karena keduanya memutuskan rantai mekanisme timbal balik sehingga meningkatkan aktifitas renin. Penghambat renin lebih efektif digunakan untuk menghambat aktifitas SRAA sehingga penghambat renin dapat digunakan sebagai obat anti-hipertensi dan memiliki efek samping yang rendah. Metode penghambatan SRAA yang juga dapat dikembangkan ialah penghambatan sintesis renin dalam kompleks jukstaglomerulus dengan cara menekan sinyal-sinyal dalam kompleks jukstaglomerulus yang merangsang sintesis renin dan menghambat fungsi taut kedap yang terdapat dalam kompleks jukstaglomerulus. Kata kunci: kompleks juksta glomerulus, resistensi vaskular, SRAA.


2021 ◽  
Vol 4 (Special2) ◽  
pp. 389-394
Author(s):  
Angela Madalina Lazar

Currently, there is a persisting dispute regarding the renin-angiotensin-aldosterone-system (RAAS) inhibitors' safety of use in COVID-19 pandemics. On one side, RAAS inhibitors appear to determine an overexpression of ACE2, the receptor of SARS-CoV-2. Therefore, they could increase the risk of SARS-CoV-2 infection and its degree of severity. On the other side, the discontinuation of RAAS leads to cardiovascular decompensation and has been discouraged by the major medical societies. Also, large-cohort studies report beneficial or at least neutral effects for the RAAS inhibitors in COVID-19 patients. Worldwide, millions of patients receive RAAS inhibitors for the treatment of hypertension and other important comorbidities. In this context, knowledge of the exact effect of these medications becomes of crucial significance. This paper aims to fill in a gap in the current knowledge and presents a putative mechanism by which RAAS inhibitor administration's beneficial results can be explained better. RAAS inhibitors can be beneficial, as they counteract the excessive detrimental activation of the classical angiotensin-converting enzyme (ACE) axis, decreasing the angiotensin II levels. The angiotensin receptor blockers (ARBs) increase the angiotensin II levels, while the angiotensin-converting enzyme inhibitors (ACEI) increase the angiotensin I levels; these substrates will compete with the SARS-CoV-2 for the ACE2 binding, decreasing the viral infectivity. In addition, following the RAAS inhibitors treatment, the up-regulated ACE2 will cleave these substrates (angiotensin I and II), particularly to angiotensin 1-7 that possesses vasodilator, protective effects.


2002 ◽  
Vol 13 (4) ◽  
pp. 1025-1033
Author(s):  
Frank G. H. van der Kleij ◽  
Paul E. de Jong ◽  
Rob H. Henning ◽  
Dick de Zeeuw ◽  
Gerjan Navis

ABSTRACT. Angiotensin-converting enzyme (ACE) activity is increased in the DD genotype, but the functional significance for renal function is unknown. Blunted responses of BP and proteinuria to ACE inhibition among DD renal patients during periods of high sodium intake were reported. It was therefore hypothesized that sodium status affects the phenotype in the ACE I/D polymorphism. The effects of angiotensin I (AngI) and AngII among 27 healthy subjects, with both low (50 mmol sodium/d) and liberal (200 mmol sodium/d) sodium intakes, were studied. Baseline mean arterial pressure (MAP) values, renal hemodynamic parameters, and renin-angiotensin system parameters were similar for all genotypes with either sodium intake level. With liberal sodium intake, the increases in MAP, renal vascular resistance, and aldosterone levels during AngI infusion (8 ng/kg per min) were significantly higher for the DD genotype, compared with the ID and II genotypes (all parameters presented as percent changes ± 95% confidence intervals), with mean MAP increases of 22 ± 2% (DD genotype), 13 ± 5% (ID genotype), and 12 ± 6% (II genotype) (P < 0.05), mean increases in renal vascular resistance of 100.1 ± 19.7% (DD genotype), 73.0 ± 16.3% (ID genotype), and 63.2 ± 16.9% (II genotype) (P < 0.05), and increases in aldosterone levels of 650 ± 189% (DD genotype), 343 ± 71% (ID genotype), and 254 ± 99% (II genotype) (P < 0.05). Also, the decrease in GFR was more pronounced for the DD genotype, with mean decreases of 17.9 ± 4.7% (DD genotype), 8.8 ± 3.4% (ID genotype), and 6.4 ± 5.9% (II genotype) (P < 0.05). The effective renal plasma flow, plasma AngII concentration, and plasma renin activity values were similar for the genotypes. In contrast, with low sodium intake, the responses to AngI were similar for all genotypes. The responses to AngII were also similar for all genotypes, with either sodium intake level. In conclusion, the responses of MAP, renal hemodynamic parameters, and aldosterone concentrations to AngI are enhanced for the DD genotype with liberal but not low sodium intake. These results support the presence of gene-environment interactions between ACE genotypes and dietary sodium intake.


2012 ◽  
Vol 11 (1) ◽  
pp. e90-e90a
Author(s):  
H. Takeshita ◽  
M. Yokoyama ◽  
Y. Fujii ◽  
K. Chiba ◽  
J. Ishioka ◽  
...  

Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Jorge F Giani ◽  
Tea Djandjoulia ◽  
Nicholas Fetcher ◽  
Sebastien Fuchs ◽  
Dale M Seth ◽  
...  

Introduction: The responses to chronic angiotensin (Ang) II infusions of gene-targeted mice lacking kidney angiotensin-converting enzyme (ACE), in terms of intrarenal Ang II accumulation, hypertension, sodium and water retention are all blunted or absent. The objective of this study was to determine if these reduced responses were associated with changes in the intrarenal renin-angiotensin system (RAS). METHODS: Mice lacking intrarenal ACE (ACE10/10) were generated by targeted homologous recombination placing the expression of ACE only in macrophages. As a result, these mice have normal circulating ACE levels, but no kidney ACE. Wild-type (WT) mice of the same background (C57Bl/J) served as controls. Mice were subjected to sham-operation or subcutaneous infusion of Ang II for two weeks (n=6-10, 400 ng/kg/min via osmotic minipump). Mean arterial pressure (MAP) was followed by telemetry. At the end of the experiment, the kidneys were collected for analysis. Ang II content was measured by RIA. Renal abundance of ACE, angiotensinogen (AGT) and Ang II receptor type 1 (AT1R) were determined by Western Blot in total kidney homogenates. Results: At baseline, the MAP of WT and ACE 10/10 mice was similar 110 ± 4 mmHg vs. 109 ± 3 mmHg respectively (p>0.05). However, when subjected to chronic Ang II infusions, the hypertensive response was blunted in ACE 10/10 mice (129 ± 6 mmHg) vs. WT (146 ± 5 mmHg; P<0.05). Also, intrarenal Ang II accumulation was lower in ACE10/10 mice (724 ± 81 fmol/g) vs. WT (1130 ± 105 fmol/g, p<0.05). In non-treated mice, intrarenal RAS components analysis revealed that the absence of ACE in ACE10/10 mice was accompanied by a significant reduction in AGT (0.41 ± 0.06) and increased AT1R expression (1.32 ± 0.05) when compared to WT (normalized to 1.00, p<0.05 in both instances). Importantly, after chronic Ang II infusions, AGT, ACE and AT1R expression increased in WT (1.36, 1.26 and 1.17 fold increase respectively compared to non-treated WT, p<0.05) but not in the ACE10/10 mice (1.19, 1.06, 0.89 fold increase respectively compared to non-treated ACE10/10, p>0.05). Conclusion: The blunted hypertension and Ang II accumulation of mice devoid of kidney ACE in response to Ang II infusions is associated with a failed induction of renal AGT and the AT1R.


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