The present study was aimed at investigating the regulation of atrial natriuretic peptide (ANP) system in association with either enhanced or attenuated activity of the renin-angiotensin system (RAS). The cardiac tissue mRNA and peptide levels of ANP were measured in rats with two-kidney, one clip (2K1C) or deoxycorticosterone acetate (DOCA)-salt hypertension. Plasma renin concentration was increased in 2K1C hypertension along with increases of renin mRNA and protein contents in the clipped kidney. On the contrary, it was suppressed in DOCA-salt hypertension along with decreases of renin mRNA and protein contents in the remaining kidney. The plasma ANP concentration was similarly increased in both models of hypertension. The cardiac tissue ANP contents were not significantly changed, but the tissue ANP mRNA levels were upregulated in the hypertrophied heart in these two models of hypertension. It is suggested that the cardiac ANP system is transcriptionally enhanced by cardiac hypertrophy associated with hypertension, independent of the systemic RAS.
Animal ; Atrial Natriuretic Factor/metabolism* ; Desoxycorticosterone ; Gene Expression Regulation ; Hypertension/metabolism* ; Hypertension/chemically induced ; Male ; Myocardium/pathology ; Organ Weight ; Peptides ; RNA, Messenger/analysis ; Rats ; Rats, Sprague-Dawley ; Renin/genetics* ; Renin/blood* ; Renin-Angiotensin System/physiology

PURPOSE: Plasma levels of renin, angiotensin II and aldosterone are increased during normal pregnancy. However, these values in preeclampsia are decreased to nearly that of a nonpregnant subject, and vascular sensitivity to angiotensin II is increased. In preeclampsia, aldosterone is decreased less than rennin. Therefore current studies were undertaken to determine the relationship between aldosterone to renin ratio (ARR) and uterine artery perfusion via RI value. MATERIALS AND METHODS: In this study, the relationship between plasma aldosterone and renin concentration was determined in 27 preeclamptic women and 50 normal pregnant women, whose gestational weeks were matched. The aldosterone to renin ratio was calculated and compared between the two groups. Doppler velocimetry of the uterine artery, which was used to calculate resistance index (RI), was performed on all subjects. The relationship between ARR and RI value was reviewed. RESULTS: In the preeclampsia group, RI value of the uterine artery was significantly higher than that of normal pregnant women. Both plasma renin and aldosterone concentrations were lower in the preeclampsia group. However, the ratio of these two parameters was significantly higher (38.3 vs. 16.1, p < 0.001); the greater ARR, the higher the RI of the uterine artery (r(2)=0.053, p=0.048). CONCLUSION: This study demonstrates that a high aldosterone to renin ratio may have a negative effect on perfusion of the uterine artery and play an important role in the pathophysiology of preeclampsia.
Adult ; Aldosterone/*blood ; Arteries/metabolism ; Case-Control Studies ; Female ; Gestational Age ; Health ; Humans ; Pre-Eclampsia/*blood ; Pregnancy ; Renin/*blood ; Uterus/*blood supply/*metabolism

OBJECTIVETo assess plasma renin activity (PRA) of renal veins in patients with unilateral renal artery atherosclerotic stenosis and its relationship with blood pressure changes after renal artery stenting.

METHODSFifty patients with significantly unilateral renal artery stenosis (lumen loss > or = 70%) and coronary artery stenosis were included. Bilateral renal vein and peripheral PRA and angiotensin II were determined and their relations with blood pressure changes after stenting were analyzed.

RESULTSAll patients were revascularized successfully for both coronary and renal artery stenosis. PRA in the ischemic kidney was significantly higher than that in the contralateral kidney (1.44 +/- 1.73 ng.ml(-1).h(-1) vs 1.27 +/- 1.57 ng.ml(-1).h(-1), P = 0.04). Ischemic and contralateral renal vein renin ratio (RVRR) was > or = 1.5 in 14 patients (28%) (renal vascular hypertension, RVH group). During follow-up (12 +/- 9 months), blood pressure returned to normal in 9 patients after revascularization, 7 were of RVH group (50%) and 2 were in control group (6%) (P < 0.001). Multivariate logistic analysis indicated RVRR > or = 1.5 was significantly related to the decrease of hypertension after renal artery stenting (OR = 3.15, 95% CI = 1.49 approximately 5.97, P = 0.02).

CONCLUSIONSPRA was significantly increased in the ischemic kidney in about one-third of patients with unilateral renal artery stenosis. Hypertension could be controlled easily to normal value after renal artery stenting in half of the patients with RVRR > or = 1.5. Measurement of renal vein renin activity in patients with renal artery stenosis is very useful in evaluating the effects of renal artery stenting on hypertension.

Aged ; Angiotensin II ; blood ; Blood Pressure ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Renal Artery Obstruction ; metabolism ; Renal Veins ; metabolism ; secretion ; Renin ; metabolism

Chronic stable diabetic patients (n = 6) were compared with healthy control subjects (n = 5) after acute oral intake of 50 mEq of potassium chloride (KCl) to investigate for possible derangements of homeostatic responses for acute term (3 hrs) to acute potassium load. Plasma renin activity (PRA), plasma aldosterone (PA), and transtubular potassium concentration gradient (TTKG) known as a useful semiquantative index of distal nephron potassium secretion were measured. All the baseline parameters were comparable between diabetic and non-diabetic subjects except for significantly reduced creatinine clearance in diabetics (mean +/- SEM, 105 +/- 4 vs. 85 +/- 5 ml/min, p < 0.05). Following acute oral KCl load, the peak increases of serum potassium changes from basal levels were noted at 2 hours in both groups, but were higher in diabetic subjects (mean +/- SEM, 0.42 +/- 0.06 vs. 0.62 +/- 0.09 mEq/L). Also, 4 out of 6 diabetic subjects but none of the control subjects at 2 hours after oral KCl load became hyperkalemic ( > 5.0 mEq/L). PRA did not show any significant changes, whereas PA was increased simultaneously with increments in serum potassium in both groups, with blunted increases in the diabetics. However, TTKG was increased prominently in control subjects (8.18 from 4.98), but only slightly in diabetic subjects (4.55 from 4.18), with statistical difference between the two groups (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
Adult ; Aged ; Aldosterone/blood ; Diabetes Mellitus, Type 2/*metabolism ; *Homeostasis ; Humans ; Kidney Tubules/metabolism ; Male ; Middle Aged ; Potassium/*metabolism ; Renin/blood

Korean Ginseng (Panax C.A. Meyer) has survived empirical efficacy as tonic and geriatric agents for several thousands of years in oriental herbal medicine. But there has been numerous controversial reports about its use in aged hypertensive men due to its allegedly hypertensive effects. Therefore, the author conducted the pharmacological studies of Korean Ginseng extracts on the blood pressure and blood lipid metabolism, during development of hypertension, using SHR(Spontaneously Hypertensive Rat), counterpart model of human essential hypertension. The results obtained were as follows: 1. SHR could be grouped, according to their age, as prehypertensive stage(<6th week after birth), labile hypertensive stage(6th 14th week), early established hypertensive stage(14th-20th week), and late established hypertensive stage(>20th week). 2. Plasma renin activity tended to rise steadily, until established hypertensive stage was reached. Thereafter, plasma renin activity tended to decline. 3. The changes of blood pressure due to Ginseng extract, depended on the amount, route and duration of its administration. Low dose of Ginseng tended to increase blood pressure but high dose of Ginseng tended to decrease blood pressure, until 1 week of intraperitonal administration. But prolonged administration of Ginseng extract beyond 1 week, showed delayed hypertensive effect in the intraperitoneal administration but not in oral administration. 4. SHR seemed to have abnormalities in the lipid metabolism. SHR showed lowered level of serum cholesterol and phospholipid, whereas slightly higher level of triglyceride, and showed lower alpha-lipoprotin fraction but higher pre beta-lipoprotein fraction, as compared with NCR.(=Normal Control Rat). 5. When high fat cholesterol salt diet was fed on, it was possible to indece hyperlidemia and increment of hypertension in SHR. but when high fat cholesterol salt diet and Ginseng extract were fed on concomitantly, Ginseng showed significant inhibiting effect on the development of hyperlidemia and hypertension.
Administration, Oral ; Blood Pressure* ; Cholesterol ; Diet ; Herbal Medicine ; Humans ; Hypertension* ; Lipid Metabolism* ; Male ; Panax* ; Plasma ; Rats, Inbred SHR* ; Renin ; Triglycerides

OBJECTIVETo investigate the effect of tanshinone II(A) on the expression of different components in the renin-angiotensin system of left ventricles of renal hypertensive rats.

METHODThe renal hypertension model was established in rats by the two-kidney-one-clip (2K1C) method. In the experiment, all of the rats were randomly divided into four groups (n = 15 per group) before the operation: the sham-operated (Sham) group, the hypertensive model (Model) group, the low-dose tanshinone II(A) group and the high-dose tanshinone II(A) group. At 5 week after the renal artery narrowing, the third and fourth groups were administered with 35 mg kg(-1) x d(-1) and 70 mg x kg(-1) x d(-1) of tanshinone II(A), respectively. The blood pressure in rats was determined by the standard tail-cuff method in each week after the operation. After the drug treatment for 8 weeks, all the rats were put to death, and their left ventricles were separated to determine the ratio of left ventricle weight to body weight (LVW/BW), the myocardial collagen content, and the expressions of different components in myocardial RAS, including angiotensin converting enzyme (ACE), angiotensin converting enzyme 2 (ACE2), angiotensin 1-type receptor (AT1R), Mas receptor mRNA expression and angiotensin II (Ang II) and angiotensin (1-7) [Ang (1-7)] content.

RESULTCompared with the sham group, the hypertensive model group exhibited a markable increase in the content of Ang II and Ang (1-7) and the mRNA expressions of ACE, ACE2, AT1R and Mas (P < 0.01). However, the treatment with tanshinone II(A) showed the does dependence, inhibited left ventricle hypertrophy, decreased myocardial Ang II content and the mRNA expression of ACE and AT, R in renal hypertensive rats (P < 0. 01) , further increased the myocardial Ang (1-7) content and the mRNA expression of ACE2 and Mas (P < 0.01) , but without any change in the blood pressure of hypertensive rats.

CONCLUSIONThe treatment with tanshinone II(A) could inhibit left ventricle hypertrophy of renal hypertensive rats. Its mechanism may be partially related to the expression of different components in the renin-angiotensin system for regulating myocardial tissues.

Angiotensin I ; genetics ; metabolism ; Angiotensin II ; genetics ; metabolism ; Animals ; Blood Pressure ; drug effects ; Diterpenes, Abietane ; administration & dosage ; Heart Ventricles ; drug effects ; metabolism ; Humans ; Hypertension ; drug therapy ; genetics ; metabolism ; physiopathology ; Male ; Peptide Fragments ; genetics ; metabolism ; Peptidyl-Dipeptidase A ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Renin ; genetics ; metabolism ; Renin-Angiotensin System ; drug effects

OBJECTIVES: Spontaneously hypertensive rats (SHR) are frequently used as rat models of essential hypertension. The mechanism for the development of hypertension is complicated and it is unknown. The renin-angiotensin system (RAS) plays a key role in the control of blood pressure. Microarrays are a powerful tool for studying genetics. The purpose of this study was to investigate changes of gene expression in the heart tissues of SHR after losartan treatment to provide basic data that is useful in the early diagnosis of hypertension and gene treatment. METHODS: Rats were divided into three groups: the control (C) group; the hypertension (H) group (SHR), and the losartan (L) group; treated with losartan (10 mg/kg/day) in SHR. Rats were sacrificed at week 5 and microarray analysis was performed. RESULTS: 102 gene expressions including the genes associated with cell proliferation such as Raf1, Uchl1, Btla, Spock1 were increased. The other 139 gene expressions, including the genes related to the regulation of metabolism such as TFIID, Auf1, Bmp, Hub, Taf51 showed decreases in gene expression. A total of 31 genes were differentially expressed in the L group compared to the H group. Of these, 16 genes including the genes associated with macromolecule metabolism such as MGC105766, Ppp1r1a, Rpl3l showed increased expression. The other 15 genes including the genes associated with primary metabolism such as Mcpt4, Ngn3, Tdo, Ak2 Hyal2 showed decreased expressions. CONCLUSION: According to microarray analysis, there was significant gene expression change in SHR compared with normal rats as well as significant gene expression changes after losartan treatment in SHR.
Animals ; Blood Pressure ; Cell Proliferation ; Early Diagnosis ; Gene Expression ; Genetics ; Heart* ; Hypertension ; Losartan* ; Metabolism ; Microarray Analysis* ; Models, Animal ; Rats ; Rats, Inbred SHR* ; Renin-Angiotensin System ; Transcription Factor TFIID

OBJECTIVETo investigate the variation of seminal plasma angiotension II (Ang II) in infertile men and its clinical implication.

METHODSAng II values in paired blood plasma and seminal plasma from 43 infertile men(13 azoospermia, 8 asthenozoopermia, 17 asthenozoospermia and 5 cases with normal semen parameters) and 10 normal controls were obtained by SPE-HPLC-RIA. All semen samples with spermatozoa were analyzed by CASA for sperm count, motility and other parameters. Acrosome reaction rate (AR) was assessed by triple-stain.

RESULTSThe mean concentration of seminal plasma Ang II was 4 times as high as that of blood plasma in all patients and controls (P < 0.01), but there was no correlation between them. The seminal plasma Ang II of azoospermic patients was higher than that of other infertile men and controls(P < 0.05), but no difference was found between the latter two groups. There was no correlation between seminal plasma Ang II values and other traditional parameters of sperm together with AR.

CONCLUSIONSSeminal plasma Ang II may be secreted locally in male reproductive tract. In addition to testis and epididymis, prostate and/or seminal vesicle may also be the source of it. The reason why seminal plasma Ang II of azoospermic patients is higher than that of others remains unknown. Further study is required to clarify the exact role of seminal plasma Ang II in the mechanisms of male fertility regulation.

Acrosome ; physiology ; Adult ; Angiotensin II ; analysis ; blood ; physiology ; Chromatography, High Pressure Liquid ; Humans ; Infertility, Male ; etiology ; metabolism ; Male ; Radioimmunoassay ; Renin-Angiotensin System ; physiology ; Semen ; chemistry

OBJECTIVE: To study the effect of 6-week intensive training on renal function in rats and the mechanism of exercise-induced proteinuria. METHODS: Thirty-six male SD rats, aged 6 weeks, were divided into two groups, including a control group(C,=12)and an overtraining group(M,=24). After the rats adapted to feeding for 4 d, group C did not carry out any exercise, and the M group did 6-week of increasing load swimming, 6 days a week, once a day. Started with the load of 1%weight at the beginning of the 4 week,and gradually increased (to 6% weight). Took a single urine from both groups 30 min after the end of the training. Blood was taken from the main ventral vein, and the bilateral kidneys were to be tested. The levels of tested urine protein, microalbumin and neutrophil gelatinase associated lipocalin(NGAL) was determined by using enzyme linked immunosorbent assaytest. The content of urine creatinine was tested with alkaline picric acid method,. The serum levels of colorimetric method to determine serum creatinine and urea nitrogen were determined by colorimetric method. The expression of Nephrin in renal tissue was detected by Western blot and the radioimmunoassay was used to test serum testosterone, corticosterone and renin-angiotensin system related index. RESULTS: Compared with group C, the serum testosterone/cortisone(T/C) of group M was decreased significantly (<0.01). The urine total protein(TP), microalbumin (mAlb), microalbumin/creatinine (mAlb/CRE), NGAL, blood urea nitrogen (BUN) and serum creatinine(SCr) were increased significantly (<0.01). The abnormality of glomerular structure was obvious, and the paller scores were higher. The protein expression of Nephrin was obviously down decreased (<0.01). The renin activity (Ra) and angiotension Ⅱ (Ang Ⅱ) in renal and circulating blood were decreased significantly (<0.01). CONCLUSIONS The effects of 6-week intensive training on renal function in rats and the mechanism of exercise-induced proteinuria may be that overtraining can induce the continuous excitation of Reninrenin activity in renal and circulating blood, down-regulated the expression of Nephrin, lead to abnormality of renal structure and function, and proteinuria.
Animals ; Blood Urea Nitrogen ; Corticosterone ; blood ; Creatinine ; blood ; Kidney ; physiopathology ; Male ; Membrane Proteins ; metabolism ; Physical Conditioning, Animal ; adverse effects ; Proteinuria ; Rats ; Rats, Sprague-Dawley ; Renin-Angiotensin System ; Testosterone ; blood

Fructose intake has increased dramatically over the past century and the upward trend has continued until recently. Increasing evidence suggests that the excessive intake of fructose induces salt-sensitive hypertension. While the underlying mechanism is complex, the kidney likely plays a major role. This review will highlight recent advances in the renal mechanisms of fructose-induced salt-sensitive hypertension, including (pro)renin receptor-dependent activation of intrarenal renin-angiotensin system, increased nephron Na transport activity via sodium/hydrogen exchanger 3 and Na/K/2Cl cotransporter, increased renal uric acid production, decreased renal nitric oxide production, and increased renal reactive oxygen species production, and suggest actions based on these mechanisms that have therapeutic implications.
Blood Pressure ; Fructose ; adverse effects ; Humans ; Hypertension ; chemically induced ; physiopathology ; Kidney ; physiopathology ; Nitric Oxide ; metabolism ; Reactive Oxygen Species ; metabolism ; Renin-Angiotensin System ; Sodium Chloride, Dietary ; adverse effects ; Sodium-Hydrogen Exchanger 3 ; metabolism ; Uric Acid ; metabolism