Exaggerated blood pressure response to angiotensin II in patients with Cushing's syndrome due to adrenocortical adenoma

1994 ◽  
Vol 131 (6) ◽  
pp. 582-588 ◽  
Author(s):  
Gen Yasuda ◽  
Hiroshi Shionoiri ◽  
Satoshi Umemura ◽  
Izumi Takasaki ◽  
Masao Ishii

Yasuda G, Shionoiri H, Umemura S, Takasaki I, Ishii M. Exaggerated blood pressure response to angiotensin II in patients with Cushing's syndrome due to adrenocortical adenoma. Eur J Endocrinol 1994:131:582–8 ISSN 0804–4643 We studied the roles played by the renin-angiotensin system in inducing hypertension in nine patients with Cushing's syndrome (CS) resulting from adrenocortical adenoma, and compared them with those in patients with primary aldosteronism (PA), renovascular hypertension (RVH) and essential hypertension (EH). In the CS group, each parameter, including serum potassium, plasma renin activity, plasma aldosterone, deoxycorticosterone and corticosterone concentrations, is within the normal range. However, plasma renin activity in the CS group was lower than that in the RVH group but higher than that in the PA group, and plasma aldosterone concentration was lower than that in each RVH or PA group. These findings indicated that the CS group had a different type of hypertension from that in either RVH or PA, in which the renin angiotensin system or mineralocorticoids play an important role in hypertension. Meanwhile, captopril (50 mg) administration either with or without indomethacin pretreatment decreased the mean blood pressure in the CS group, although captopril failed to change it in the PA group or in normal subjects. Furthermore, the pressor response to exogenous angiotensin II in the CS group was higher than that in the RVH or EH group, but was not different from that in the PA group. Thus, the hypertension in patients with CS due to adrenocortical adenoma appears to be mediated through a change in the renin-angiotensin system in the form of exaggerated pressor responses to angiotensin II. G Yasuda, Second Department of Internal Medicine, Yokohama City University School of Medicine, 3-46 Urafune, Minami, Yokohama 232, Japan

1980 ◽  
Vol 58 (1) ◽  
pp. 15-20 ◽  
Author(s):  
H. Thurston ◽  
R. F. Bing ◽  
E. S. Marks ◽  
J. D. Swales

1. Removal of the renal artery constriction but not of the clipped kidney restored the blood pressure to normal levels in Goldblatt two-kidney rats with hypertension of more than 4 months' duration. 2. Despite the differences in blood pressure response, both surgical procedures lowered plasma renin concentration to normal or below normal values. 3. Administration of the oral converting enzyme inhibitor SQ 14 225 produced a marked fall in blood pressure in Goldblatt kidney rats with chronic hypertension. However, a prolonged infusion of the angiotensin II antagonist saralasin was quite ineffective. The difference in response to the two inhibitors may have been due to bradykinin potentiation by the converting enzyme inhibitor. 4. Although plasma renin is often elevated in Goldblatt two-kidney rats with hypertension of more than 4 months' duration, the renin-angiotensin system plays no role in the maintenance of blood pressure at this stage.


1979 ◽  
Vol 236 (3) ◽  
pp. H409-H416 ◽  
Author(s):  
M. Shibota ◽  
A. Nagaoka ◽  
A. Shino ◽  
T. Fujita

The development of malignant hypertension was studied in stroke-prone spontaneously hypertensive rats (SHR) kept on 1% NaCl as drinking water. Along with salt-loading, blood pressure gradually increased and reached a severe hypertensive level (greater than 230 mmHg), which was followed by increases in urinary protein (greater than 100 (mg/250 g body wt)/day) and plasma renin concentration (PRC, from 18.9 +/- 0.1 to 51.2 +/- 19.4 (ng/ml)/h, mean +/- SD). At this stage, renal small arteries and arterioles showed severe sclerosis and fibrinoid necrosis. Stroke was observed within a week after the onset of these renal abnormalities. The dose of exogenous angiotensin II (AII) producing 30 mmHg rise in blood pressure increased with the elevation of PRC, from 22 +/- 12 to 75 +/- 36 ng/kg, which was comparable to that in rats on water. The fall of blood pressure due to an AII inhibitor, [1-sarcosine, 8-alanine]AII (10(microgram/kg)/min for 40 min) became more prominent with the increase in PRC in salt-loaded rats, but was not detected in rats on water. These findings suggest that the activation of renin-angiotensin system participates in malignant hypertension of salt-loaded stroke-prone SHR rats that show stroke signs, proteinuria, hyperreninemia, and renovascular changes.


1983 ◽  
Vol 64 (5) ◽  
pp. 463-470
Author(s):  
Y. Takata ◽  
A. E. Doyle ◽  
M. Veroni ◽  
S. G. Duffy

1. Blood pressure, the hypotensive effect of captopril, plasma renin activity, renal renin content and kidney weight were measured in the two-kidney—one-clip model, the one-kidney—one-clip model and the two-kidney—one-clip model with the ureter of the contralateral kidney ligated in rats. The ureteric ligation was performed to abolish urinary excretion from the contralateral kidney in the two-kidney—one-clip model. 2. The development of hypertension after renal artery constriction was earlier and greater in the one-kidney—one-clip model and the two-kidney—one-clip model with ureter of the contralateral kidney ligated than in the two-kidney—one-clip model. A single oral dose of captopril produced a greater fall in blood pressure in both the two-kidney models than in the one-kidney—one-clip group. 3. Plasma renin activity and renal renin content of the clipped kidney were higher in the two-kidney model rats, whether or not the ureter had been ligated, than in the one-kidney—one-clip model animals, although more than half the rats from the two-kidney model had normal values. There was a significant correlation between plasma renin activity and the response to captopril in all groups, whereas in none of the three groups was the correlation between plasma renin activity and blood pressure significant. 4. The clipped kidney had a higher renin content than did the contralateral kidney, and the weight of the ischaemic kidney was decreased compared with the contralateral kidney whether it was untouched or had its ureter ligated. The weight of the clipped kidney was in the order one-kidney—one-clip model > two-kidney—one-clip model with ureter of the contralateral kidney ligated > two-kidney—one-clip model. 5. It was concluded that the renin-angiotensin system was stimulated to the similar degree in some animals for the two-kidney—one-clip models, whether or not the ureter of the contralateral kidney had been ligated, compared with the one-kidney—one-clip animals. This finding suggests that the contralateral kidney can stimulate renin secretion and synthesis in the clipped kidney independently of Na+ excretion.


1982 ◽  
Vol 243 (1) ◽  
pp. E48-E51 ◽  
Author(s):  
H. Suzuki ◽  
M. Handa ◽  
K. Kondo ◽  
T. Saruta

The role of the renin-angiotensin system in the regulation of the blood pressure of dexamethasone-treated rats (Dex) was evaluated using saralasin, an angiotensin II antagonist, and SQ 14225 (SQ) (d-3-mercapto-2-methylpropranoyl-1-proline), an angiotensin-converting enzyme inhibitor. During a 7-day period blood pressure rose 65 +/- 10 mmHg (P less than 0.001) in Dex with no significant changes in plasma renin activity. Concurrent administration of dexamethasone and SQ attenuated the elevation of blood pressure (P less than 0.05). In the conscious, freely moving state, intravenous injection of SQ (10, 30, 100 micrograms/kg) reduced blood pressure of DEX in a dose-dependent manner (P less than 0.05). Also, intravenous injection of saralasin (10 micrograms.kg-1 . min-1) reduced blood pressure significantly (P less than 0.01). Bilateral nephrectomy abolished the effects of saralasin and SQ on blood pressure in Dex. These results indicate that the elevation of blood pressure in DEX depends partially on the renin-angiotensin system.


PPAR Research ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
María Sánchez-Aguilar ◽  
Luz Ibarra-Lara ◽  
Leonardo Del Valle-Mondragón ◽  
María Esther Rubio-Ruiz ◽  
Alicia G. Aguilar-Navarro ◽  
...  

Rosiglitazone (RGZ), a peroxisome proliferator-activated receptor gamma (PPARγ) ligand, has been reported to act as insulin sensitizer and exert cardiovascular actions. In this work, we hypothesized that RGZ exerts a PPARγ–dependent regulation of blood pressure through modulation of angiotensin-converting enzyme (ACE)-type 2 (ACE2)/angiotensin-(1-7)/angiotensin II type-2 receptor (AT2R) axis in an experimental model of high blood pressure. We carried on experiments in normotensive (Sham) and aortic coarctation (AoCo)-induced hypertensive male Wistar rats. Both sham and AoCo rats were treated 7 days with vehicle (V), RGZ (5 mg/kg/day), or RGZ+BADGE (120 mg/kg/day) post-coarctation. We measured blood pressure and vascular reactivity on aortic rings, as well as the expression of renin-angiotensin system (RAS) proteins. We found that RGZ treatment in AoCo group decreases blood pressure values and improves vascular response to acetylcholine, both parameters dependent on PPARγ-stimulation. RGZ lowered serum angiotensin II (AngII) but increased Ang-(1-7) levels. It also decreased 8-hydroxy-2′-deoxyguanosine (8-OH-2dG), malondialdehyde (MDA), and improved the antioxidant capacity. Regarding protein expression of RAS, RGZ decreases ACE and angiotensin II type 1 receptor (AT1R) and improved ACE2, AT2R, and Mas receptor in AoCo rats. Additionally, an in silico analysis revealed that 5′UTR regions of RAS and PPARγ share motifs with a transcriptional regulatory role. We conclude that RGZ lowers blood pressure values by increasing the expression of RAS axis proteins ACE2 and AT2R, decreasing the levels of AngII and increasing levels of Ang-(1-7) in a PPARγ-dependent manner. The in silico analysis is a valuable tool to predict the interaction between PPARγ and RAS.


2019 ◽  
Vol 20 (1) ◽  
pp. 147032031983440 ◽  
Author(s):  
Zhongming Zhang ◽  
Yijing Zhang ◽  
Yan Wang ◽  
Shengchen Ding ◽  
Chenhui Wang ◽  
...  

Introduction: Brain-derived neurotropic factor (BDNF) is expressed throughout the central nervous system and peripheral organs involved in the regulation of blood pressure, but the systemic effects of BDNF in the control of blood pressure are not well elucidated. Materials and methods: We utilized loxP flanked BDNF male mice to cross with nestin-Cre female mice to generate nerve system BDNF knockdown mice, nestin-BDNF (+/–), or injected Cre adenovirus into the subfornical organ to create subfornical organ BDNF knockdown mice. Histochemistry was used to verify injection location. Radiotelemetry was employed to determine baseline blood pressure and pressor response to angiotensin II (1000 ng/kg/min). Real-time polymerase chain reaction was used to measure the expression of renin–angiotensin system components in the laminal terminalis and peripheral organs. Results: Nestin-BDNF (+/–) mice had lower renin–angiotensin system expression in the laminal terminalis and peripheral organs including the gonadal fat pad, and a lower basal blood pressure. They exhibited an attenuated hypertensive response and a weak or similar modification of renin–angiotensin system component expression to angiotensin II infusion. Subfornical organ BDNF knockdown was sufficient for the attenuation of angiotensin II-induced hypertension. Conclusion: Central BDNF, especially subfornical organ BDNF is involved in the maintenance of basal blood pressure and in augmentation of hypertensive response to angiotensin II through systemic regulation of the expression of renin–angiotensin system molecules.


1984 ◽  
Vol 62 (2) ◽  
pp. 137-147 ◽  
Author(s):  
John X. Wilson

The mammalian renin–angiotensin system appears to be involved in the maintenance of blood volume and pressure because (i) sodium depletion, hypovolemia, and hypotension increase renin levels, and (ii) administration of exogenous angiotensin II rapidly increases mineralocorticoid and antidiuretic hormone production, transepithelial ion transport, drinking behavior, and peripheral vascular resistance. Are these also the physiological properties of the renin–angiotensin system in nonmammalian species? Signals for altered levels of renin activity have yet to be conclusively identified in nonmammalian vertebrates, but circulating renin levels are elevated by hypotension in teleost fish and birds. Systemic injection of angiotensin II causes an increase in arterial blood pressure in all the vertebrates studied, suggesting that barostatic control is a universal function of this hormone. Angiotensin II alters vascular tone by direct action on arteriolar muscles in some species, but at concentrations of the hormone which probably are unphysiological. More generally, angiotensin II increases blood pressure indirectly, by acting on the sympathetic nervous system. Catecholamines, derived from chromaffin cells and (or) from peripheral adrenergic nerves, mediate some portion of the vasopressor response to angiotensin II in cyclostomes, elasmobranchs, teleosts, amphibians, reptiles, mammals, and birds. Alteration of sympathetic outflow is a prevalent mechanism through which the renin–angiotensin system may integrate blood volume, cardiac output, and peripheral vascular resistance to achieve control of blood pressure and adequate perfusion of tissues.


1981 ◽  
Vol 240 (1) ◽  
pp. R75-R80 ◽  
Author(s):  
M. C. Lee ◽  
T. N. Thrasher ◽  
D. J. Ramsay

The role of the renin-angiotensin system in drinking induced by water deprivation and caval ligation was assessed by infusion of saralasin into the lateral ventricles of rats. This technique was first validated by demonstrating its capability to specifically antagonize drinking to both systemic and central angiotensin II. However, neither the latency to drink nor the amount of water consumed following 24- or 30-h water deprivation was affected by saralasin. Furthermore, saralasin had no significant effect on the recovery of blood pressure or on the water intake following ligation of the abdominal vena cava. These observations suggest that the renin-angiotensin system alone does not play an essential role in the control of drinking following water deprivation or caval ligation in rats.


1978 ◽  
Vol 54 (6) ◽  
pp. 633-637 ◽  
Author(s):  
M. Fernandes ◽  
R. Fiorentini ◽  
G. Onesti ◽  
G. Bellini ◽  
A. B. Gould ◽  
...  

1. Sar1-Ala8-Angiotensin II (an angiotensin antagonist) was infused in rats during the development and maintenance of renal hypertension produced by aortic ligation between renal arteries. 2. In the early phase (5 and 12 days after ligation), infusion of the antagonist markedly decreased blood pressure although it did not reach normal pressures. Later (day 40) only a modest decrease in blood pressure was noted. 3. Removal of the small left kidney always decreased the blood pressure to normal pressures. 4. It is concluded that the renin—angiotensin system is the major pressor component in the initiation of this hypertension. Later, other factors of renal origin assume a pressor function.


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