Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In 10 healthy and 27 diabetic children aged 11--17 years plasma renin activity was determined in horizontal position (PRA-I) and after stimulation by furosemid and upright position (PRA-II). In diabetic children with or without hypertension and protein-uria, and a normal or only slightly elevated plasma creatinine level normal PRA-I and PRA-II values were found.
 ...
PMID:[Plasma renin activity in diabetic children (author's transl)]. 76 47

Utilizing the microsurgical method of transplantation in the rat, the role of the kidney in an experimental renal hypertension due to segmental renal infarction was studied. When the infarcted kidney was transplanted into the bilaterally nephrectomized recipient, hypertension developed so long as the donor kidney was transplanted within 2 weeks after infarction. With transplantation of the normal kidney into the hypertensive rat 8 weeks after infarction, BP remained high unless the infarcted kidney was removed. PRA after transplantation, or KRA of the transplanted kidneys were not correlated to the blood pressure levels. It was suggested that the infarcted kidney has the pressor mechanism, lasting for 2 weeks or more after infarction. The infarcted kidney also has the maintenance mechanism, establishing 8 weeks after infarction.
 ...
PMID:Role of the kidney in the development and maintenance of hypertension caused by renal segmental infarction in the rat. 79 91

Body fluid volumes, cardiac output, PRA and pressor responses to angiotensin II (AT) and norepinephrine (NE) were compared between untreated patients with essential hypertension aged younger than 35 (EH-I) and those aged older than 36 years (EH-II). Men blood volume, total body water and extracellular volume were not significantly different between the patients with essential hypertension and normotensive subjects. There were no difinite differences in each volume between the EH-I and EH-II patients either. However, the distribution of blood volume was significantly larger in the essential hypertensive patients than in the normotensive subjects, suggesting that the changes in blood volume might not be homogenous in essential hypertension. In addition, blood volume was noted to have a significant inverse correlation with PRA. Cardiac output at rest was slightly but not significantly less in the EH-I and EH-II groups than in the normotensive group. A decline in blood pressure following 'bed-rest' was accompanied by a decrease in total peripheral resistance index (TPRI). Thus, elevated peripheral vascular resistance seems to be responsible for the mild to moderate hypertension even in the younger patients. PRA and its increases in response to standing or furosemide were normal in the EH-I patients, while they were markedly suppressed in the EH-II patients as compared to the age-matched normotensive subjects. In addition, PRA had a significant inverse correlation with the blood pressure and the scores of the severity of hypertension in the patients with essential hypertension. Thus, it seems likely that low renin in essential hypertension is secondary to long-lasting hypertension. Pressor response to AT significantly correlated with mean blood pressure and that to NE did so with 24 hours' urinary sodium excretion in essential hypertensive patients. The influence of aging on the pressor responses were obscure: the relationships of the pressore responses to blood pressure or to urinary sodium excretion were not different between the EH-I and EH-II groups. The examinations were repeated in 16 patients with essential hypertension (16 to 48 year-old) in 11 to 30 days after the initial study. Twelve of the 16 patients had declines in blood pressure and TPRI at the second study. In 7 of the patients whose blood pressure declined following 'bed-rest', there were significant decreases in pressor response to AT and in blood volume and a significant increase in PRA (group A). The other 5 patients showed a significant decrease in PRA and an enhanced pressor response to NE (group B). The blood volume in the group A was significantly larger than that in the group B at the initial study. It is suggested that the cause of essential hypertension is not homogeneous in that the increased vascular resistance may have been attributed to sodium excess in some patients and to an increased sympathetic activity in others. Some additional factors remain to be taken into account to clarify the complicated aspects of essential hypertension.
 ...
PMID:Comparisons of body fluid volumes, plasma renin activity, hemodynamics and pressor responsiveness between juvenile and aged patients with essential hypertension. 87 Jul 21

Patients with chronic glomerulonephritis and mild hypertension show a consistent behaviour in their renin-aldosterone-system. There is a close correlation between the elevation of mean blood pressure and destruction of glomeruli. No correlation has been found between renin values and the degree of hypertension. Thus the cuase of mild hypertension occurring in the early stages of chronic GN remains to be elucidated. Normal PRA values in spite of hypertension and expansion of ECFV accompaning progression of chronic glomerulonephritis could be a sign of "relative hyperreninemia". Apparently various mechanisms are involved in the pathogenesis of renal hypertension. These include sodium retention, increased cardiac output. anemia, renin, aldosterone, prostaglandins, expanded plasma volume and peripheral vasoconstriction. These factors are more or less active in the different stages of hypertension and renal failure.
 ...
PMID:Plasma renin activity (PRA) and aldosterone (PA) in patients with chronic glomerulonephritis (GN) and hypertension. 94 54

1. The effect of chronic administration of propranolol on the development and maintenance of severe renal hypertension in rats subjected to unilateral renal artery constriction was studied in relation to possible changes in peripheral PRA and the blood and tissue levels of propranolol. Propranolol was administered s.c. twice daily in doses of 1, 10 and 25 mg/kg, starting 2 days before operation. 2. Contrary to expectations, not only did the initial rise in systolic blood pressure become accelerated, but the established level of hypertension attained in the propranolol treated rats was of the same severity as that attained in placebo treated rats. Moreover, the progressive rise in peripheral plasma renin activity following unilateral renal artery constriction was not affected by propranolol administration. 3. The same doses of propranolol were also administered daily for 8 days to rats with established severe hypertension. A slight further rise in blood pressure occurred initially, followed by a moderate decrease of 15-25 mmHg. Propranolol failed to exert this minor hypotensive effect in hypertensive rats treated concomitantly with furosemide. No suppressive effect on the markedly increased levels of plasma renin activity was observed in these severely hypertensive rats in the presence or absence of furosemide administration. 4. These results indicate that in severely renal hypertensive rats propranolol has only a minor hypotensive effect and no blocking action on renin release under the conditions of study.
 ...
PMID:Effects of propranolol on development and maintanance of severe renal hypertension in rats. 100 94

Hypertension persisted for longer than 6 mo or developed de novo after the first month following transplantation in seven of 77 pediatric recipients of renal allografts; concomitantly there were an elevation of PRA and renal angiographic abnormalities. In two of the four patients who developed RAS there was evidence of diminished allograft function. Successful correction of the stenotic lesion in these two recipients resulted in a return of the blood pressure, PRA, and biochemical function of the allograft to normal. Unsuccessful attempts at surgical repair led to loss of the allograft in the other two patients with RAS. Intrarenal vascular and/or parenchymal lesions were evident in the other three recipients with hypertension. Although an explanation was not apparent, subclinical rejection was hypothesized. Treatment effected reduction of the hypertension in these three patients and no deterioration of allograft function was observed for periods of 5, 34, and 38 mo, respectively. Renal angiographic studies and determinations of PRA are recommended in any pediatric recipient of an allograft who develops hypertension after the first month following transplantation or has hypertension which persists for longer than 6 mo after transplantation.
 ...
PMID:Hypertension after renal transplantation in children. 108 76

A young woman with mild to moderate hypertension and normal PRA, serum potassium levels, and urinary aldosterone excretion rate was found to have a renal tumor by selective renal arteriogram. Renal vein renin activity indicated an increased production of renin from the kidney containing the tumor. At surgery, a clear cell carcinoma of the kidney was found that contained renin activity in excess of the surrounding kidney tissue. The renin activity appeared identical to human kidney renin. Previous renin-producing tumors have been associated with severe hypertension, elevated plasma renin activity, hypokalemia, and elevated urinary aldosterone excretion. This case should call attention to the renin-secreting tumor as a cause of even mild hypertension.
 ...
PMID:Renin-secreting clear cell carcinoma of the kidney. 113 Sep 32

To test the hypothesis that renin is circulating in pressor amounts in renal hypertension, two-kidney Goldblatt hypertension was produced in rats. After hypertension had been present for a variable period of time (4 to 21 days), the ischemic kidney was removed, and an infusion of rat renin was started immediately to replace the endogenous renin that the ischemic kidney had been releasing. Since the amount of renin released by the clipped kidney was not known, the amount infused was regulated by a feedback mechanism set to keep the mean blood pressure at the same level as before ipsilateral nephrectomy. Hypertension remission was therefore prevented by this procedure. The PRA at the end of the renin infusion was similar to that prior to the ipsilateral nephrectomy. This finding indicates that the levels of the PRA circulating in renal hypertension are within the pressor range, thus supporting the hypothesis that renin plays a role in the pathogenesis of the acute or semiacute phase of renal hypertension. However, the participation of other factors cannot be ruled out since no correlation was found between PRA and blood pressure.
 ...
PMID:Role of renin in the pathogenesis of renal hypertension. 113 78

The AA. have applied the diazoxide test for the screening of primary hiperaldosteronism to 22 nephropatic patients suffering from hypertension and with different degrees of renal function. In 22 patients an increase in PRA and aldosterone values always followed the diazoxide infusion. Only one patient, likely suffering from primary aldosteronism, showed no increase in PRA and aldosterone values. The diazoxide infusion had no influence on renal, pancreatic and cardiovascular function. Therefore, this can be considered as a valid test easy to be performed in a short time, also in nephropatic patients who are very sensitive to pharmacological noxae.
 ...
PMID:[Diazoxide test in the diagnosis of arterial hypertension: modifications in the levels of renin and aldosterone in blood of patients with various restrains of the renal function]. 122 45

Twenty-eight patients with primary aldosteronism were treated from 1974 to 1990. The serum potassium concentration was higher than normal level in all patients with the exception of one whose serum potassium concentration was normal. All of 14 tested patients had low renin values. The plasma aldosterone concentration was higher than standard value in all of 5 patients, and the A/PRA ratio was more than 400. Spironolactone administered preoperatively could not only normalize serum potassium concentration level and blood pressure, but also predict postoperative prognosis of hypertension. Only 37.5% of adenomas were detected by retroperitoneal pneumography with tomography in the early period. 80.0% of adenomas were found by B-ultrasonography, and 92.8% by CT after 1982. The operation was done through abdominal incision because of indefinite localization of adenoma before 1982, and the operation was performed through lumbar incision because of definite localization of adenoma after 1982.
 ...
PMID:[Diagnosis and treatment of primary aldosteronism]. 130 99


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>