Acute and chronic actions of bradykinin on renal function and arterial pressure

1985 ◽  
Vol 248 (1) ◽  
pp. F87-F92 ◽  
Author(s):  
J. P. Granger ◽  
J. E. Hall

The present study was designed to examine the acute and chronic effects of increased levels of circulating bradykinin (BK) on control of renal hemodynamics, electrolyte excretion, and arterial pressure. Intrarenal infusion of BK (50 ng X kg-1 X min-1) for 60 min in five anesthetized dogs with renal perfusion pressure maintained at a constant level of 108 +/- 1 mmHg had no significant effect on glomerular filtration rate (GFR), whereas it increased renal blood flow (RBF) from a control value of 230 +/- 14 to 282 +/- 18, 266 +/- 15, and 253 +/- 17 ml/min after 15, 30, and 60 min of infusion, respectively. Acute intrarenal infusion of BK also increased urine volume (UV) from 0.255 +/- 0.044 to 0.523 +/- 0.103 ml/min and urinary sodium excretion (UNaV) from 5.72 +/- 1.5 to 13.7 +/- 3.4 mueq/min. To determine whether the potent acute effects of BK on RBF, UV, and UNaV lead to a chronic reduction in arterial pressure, BK (50 ng X kg-1 X min-1) was infused intrarenally for 7 days in conscious dogs. Intrarenal infusion of BK for 7 days had no significant effect on GFR, UNaV, UV, or arterial pressure. However, BK elevated renal plasma flow and decreased renal vascular resistance throughout the 7 days of infusion. Chronic intrarenal BK infusion caused no significant changes in plasma renin activity or plasma aldosterone concentration. Results from these studies indicate that although increased levels of bradykinin in the renal circulation can have potent acute effects on RBF, UV, and UNaV, these effects on UV and UNaV are not sustained and therefore do not result in long-term changes in arterial pressure.

1987 ◽  
Vol 252 (1) ◽  
pp. F91-F98
Author(s):  
R. D. Manning

The effects of long-term hypoproteinemia on renal hemodynamics, arterial pressure, and fluid volume were studied in eight conscious dogs over a 34-day period. Plasma protein concentration (PPC) was decreased by daily plasmapheresis, and the effects of decreasing and increasing sodium intake were measured. By the 12th day of plasmapheresis, during which sodium intake was 30 meq/day, PPC had decreased to 2.5 g/dl from a control value of 7.2 g/dl, mean arterial pressure had decreased to 78% of control, glomerular filtration rate (GFR) was 75.2% of control, and urinary sodium excretion was decreased. By day 18 of plasmapheresis, estimated renal plasma flow (ERPF) was decreased to 60% of control due to the decreased arterial pressure and an increase in renal vascular resistance. Also, plasma renin activity and plasma aldosterone concentration were both increased, and the relationship between mean arterial pressure and urinary sodium excretion was distinctly shifted to the left along the arterial pressure axis. In contradistinction to acute experiments, chronic hypoproteinemia results in decreases in GFR, ERPF, and urinary sodium excretion and has marked effects on both fluid volume and arterial pressure regulation.


1992 ◽  
Vol 82 (5) ◽  
pp. 543-549 ◽  
Author(s):  
D. W. Eadington ◽  
S. Freestone ◽  
C. J. Waugh ◽  
C. P. Swainson ◽  
M. R. Lee

1. Renal and systemic responses to infusion of angiotensin II (1.25 and 2.5 ng min−1 kg−1 body weight) were examined in ten normal males 12 h after single doses of 750 mg of lithium carbonate, 250 mg of lithium carbonate (n = 6) or placebo. 2. Baseline mean arterial pressure [mean (sem)] was higher after 750 mg of lithium [93.1 (1.7) versus 89.5 (1.9) mmHg, P = 0.014], and the subsequent rise in blood pressure during angiotensin II infusion was lower [8.2 (1.8) versus 12.2 (2.4) mmHg, P < 0.02]. 3. Lithium at a dose of 750 mg increased overnight urinary sodium excretion before the study. The fall in fractional sodium excretion during angiotensin II infusion was reduced after pretreatment with 750 mg of lithium [750 mg of lithium, 2.73 (0.24) to 1.34 (0.08)%; placebo, 2.69 (0.26) to 1.01 (0.11)%; P=0.02]. The increases in effective filtration fraction [750 mg of lithium, 5.4 (1.0)%; placebo, 8.6 (0.7)%; P < 0.05] and total effective renal vascular resistance [750 mg of lithium, 3700 (390) dyn s cm−5; placebo 5100 (460) dyn s cm−5; P=0.03] during angiotensin II infusion were also attenuated after 750 mg of lithium. Responses after 250 mg of lithium did not differ from those after placebo. 4. The fall in plasma renin activity and the increase in plasma aldosterone concentration during angiotensin II infusion were similar on each study day. 5. Renal responses to exogenous angiotensin II are altered after pretreatment with a 750 mg dose of lithium in normal man. This dose of lithium is not an inert marker of sodium handling.


1995 ◽  
Vol 268 (2) ◽  
pp. R375-R381 ◽  
Author(s):  
F. C. Wilkins ◽  
A. Alberola ◽  
H. L. Mizelle ◽  
T. J. Opgenorth ◽  
J. P. Granger

Although recent studies have reported endogenous plasma endothelin levels to be elevated two- to fivefold in chronic pathophysiological states, whether such an increase in circulating endothelin levels alone can lead to significant long-term alterations in cardiovascular and renal function is not known. The purpose of this study was to examine the long-term systemic hemodynamic and renal effects of a pathophysiological increase in plasma endothelin concentration in chronically instrumented, conscious dogs (n = 7). Infusion of endothelin-1 (2.5 ng.kg-1.min-1) for 8 days increased plasma concentration of immunoreactive endothelin approximately two- to threefold from 6.7 +/- 0.4 to 16.0 +/- 2.2 pg/ml. Mean arterial pressure increased 21% from a control value of 86.7 +/- 2.1 to 105.0 +/- 2.5 mmHg during the endothelin infusion period. Cardiac output averaged 2,200 +/- 205 ml/min during control and fell by 33% on day 4 of endothelin infusion (1,484 +/- 146 ml/min) and was still 14% below control after day 8 of endothelin infusion (1,885 +/- 154 ml/min). Endothelin increased total peripheral resistance from 42.0 +/- 3.1 to 80.3 +/- 9.1 mmHg.l-1.min. Increasing plasma endothelin two- to threefold was associated with an increase in renal vascular resistance and decreases in glomerular filtration rate and renal plasma flow. Endothelin-1 had no long-term effect on plasma renin activity or aldosterone concentration. These data indicate the importance of pathophysiological levels of endothelin in controlling renal and cardiovascular function in chronic conditions. Furthermore, the results indicate that endothelin may play a role as a mediator of chronic hypertension in pathophysiological states associated with endothelial dysfunction.


1990 ◽  
Vol 259 (5) ◽  
pp. F793-F800 ◽  
Author(s):  
H. M. Siragy ◽  
R. A. Felder ◽  
N. L. Howell ◽  
R. L. Chevalier ◽  
M. J. Peach ◽  
...  

Dopamine is synthesized by the kidney, and dopamine-2 (DA2) receptors are present in the renal glomerulus. However, no role for DA2 receptors in the kidney has been defined. We investigated the possible role of DA2 receptors in control of renal function by intrarenal infusion of a highly specific DA2 antagonist YM-09151 (YM), in conscious uninephrectomized dogs (n = 5) in metabolic balance at Na intake 40 meq/day. YM infused at 0.01 pmol.kg-1.min-1 did not cause any changes in urinary flow rate or Na excretion. Administration of YM (infusions from 0.1 to 10.0 pmol.kg-1.min-1) caused a significant dose-dependent diuresis (F = 20.3; P less than 0.001) and natriuresis (F = 35.2; P less than 0.0001) and an increase in glomerular filtration rate (F = 45.4; P less than 0.0001), renal plasma flow (F = 209.3; P less than 0.0001), and filtration fraction (F = 11.2; P less than 0.0001). No significant changes in plasma renin activity, plasma aldosterone concentration, or mean arterial blood pressure occurred with any of the doses of YM infused into the renal artery. Coinfusion of LY-171555, a specific DA2 agonist, at a dose that itself did not affect renal function, completely abrogated the renal hemodynamic and excretory changes induced by YM. The data suggest that dopamine produced intrarenally may act at renal vascular and/or glomerular DA2 receptors to control renal function.


1996 ◽  
Vol 270 (3) ◽  
pp. E386-E392 ◽  
Author(s):  
G. B. Pidgeon ◽  
A. M. Richards ◽  
M. G. Nicholls ◽  
C. J. Charles ◽  
M. T. Rademaker ◽  
...  

Ouabain is claimed to be a hormone of adrenal origin, capable of raising arterial pressure in rats. We infused ouabain in conscious sheep under carefully controlled circumstances to determine its effects on blood pressure, urine electrolytes, and vasoactive hormones. Eight healthy ewes were studied while taking a constant intake of dietary sodium and potassium. Ouabain infusion at 0.25 mg daily over 22 days reduced heart rate and arterial pressure and had no effect on pressor responsiveness to incremental intravenous infusions of angiotensin II. Ouabain induced minor, but statistically significant, decrements in urine volume, urinary sodium excretion, plasma renin and angiotensin II concentrations, and a rise in plasma aldosterone and cortisol. Plasma ouabain levels averaged 1.37 +/- 0.28 nmol/l during ouabain infusion. In conclusion, high-dose chronic ouabain infusion in sheep did not elevate arterial pressure or alter pressor responsiveness to angiotensin II, was antidiuretic and antinatriuretic, and induced minor perturbations in circulating renin, angiotensin II, aldosterone, and cortisol.


1987 ◽  
Vol 72 (6) ◽  
pp. 749-756 ◽  
Author(s):  
A. P. Passmore ◽  
G. B. Kondowe ◽  
G. D. Johnston

1. The effects of increasing oral doses of caffeine (45, 90, 180 and 360 mg) on effective renal plasma flow (ERPF), plasma renin activity (PRA), serum electrolytes, plasma noradrenaline, blood pressure and heart rate were studied in eight healthy male volunteers. 2. Urine volume was increased by 360 mg of caffeine only. At caffeine doses greater than 90 mg urinary sodium excretion was significantly increased. There were no changes in ERPF. 3. Serum potassium was significantly reduced by 360 mg of caffeine. 4. Caffeine increased systolic pressure in a dose related manner. Diastolic pressure was also increased, but not in relation to dose. A 360 mg dose of caffeine produced a late increase in heart rate. These changes were not associated with any alterations in PRA or in plasma noradrenaline.


1984 ◽  
Vol 247 (2) ◽  
pp. F229-F233 ◽  
Author(s):  
K. P. Conrad ◽  
T. Brinck-Johnsen ◽  
M. Gellai ◽  
H. Valtin

We examined renal hemodynamics and arterial plasma renin activity (PRA) concurrently in trained chronically catheterized conscious rats during decreased and elevated renal arterial pressure (RAP). Control RAP had an absolute value of 112 +/- 2 mmHg (mean +/- SE). During inflation of a suprarenal aortic cuff, glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were autoregulated down to 82% of control RAP. Within this range GFR averaged 107 +/- 5% and ERPF 114 +/- 10% of the control value. During inflation of the infrarenal aortic cuff, RAP increased by 24 +/- 2% to an absolute level of 139 +/- 5 mmHg; this elevation was associated with autoregulation of both GFR (100 +/- 5% of control) and ERPF (94 +/- 6% of control). Arterial PRA had an absolute value during control conditions of 2.1 +/- 0.2 ng ANG I X ml-1 X h-1. It was not significantly altered within the autoregulatory range, being 104 +/- 10% of control during lowered RAP and 120 +/- 15% of control during elevated RAP. Nor, in separate experiments, was PRA changed significantly during the transient state, i.e., at 5, 10, or 30 min after RAP was lowered to an autoregulatory level. These studies demonstrate that, in the conscious rat, there is considerable autoregulatory capacity both below and above resting arterial pressure, and that GFR and ERPF are autoregulated concomitantly. Arterial PRA was not altered significantly within the autoregulatory range.


1993 ◽  
Vol 265 (4) ◽  
pp. E648-E654 ◽  
Author(s):  
H. M. Siragy

Bradykinin (BK) is produced by the kidney, but the role of the renal kallikrein-kinin system (KKS) in the control of renal function is not understood. We studied the effects of intrarenal infusion of the BK antagonist, D-Arg-Arg-Pro-Hyp-Gly-Thi-Ser-D-Phe-Thi-Arg-trifluoroacetic acid (BKA, n = 5) and BK (n = 4) alone or combined with antagonist (BKA 0.025 ng.kg-1 x min-1 + BK 0.25 ng.kg-1 x min-1, n = 4) in uninephrectomized conscious dogs in sodium balance at 10 and 80 meq/day. During low sodium intake, administration of BKA (infusions from 0.025 to 2.5 ng.kg-1 x min-1) caused a significant antidiuresis (P < 0.0001) and antinatriuresis (P < 0.0001) and a decrease in fractional sodium excretion (P < 0.0001). There were no changes in estimated renal plasma flow (RPF) or glomerular filtration rate during intrarenal administration of BKA at 0.025 and 0.25 ng.kg-1 x min-1. A dose of 2.5 ng.kg-1 x min-1 BKA caused a significant decrease in RPF. There were no changes in plasma aldosterone concentration, plasma renin activity, or systemic arterial pressure during intrarenal BKA administration. At 80 meq/day sodium balance (n = 5), intrarenal administration of BKA did not cause any systemic or renal effects. Intrarenal administration of BK at 0.25 ng.kg-1 x min-1 during low sodium balance caused an increase in urine flow rate and urinary sodium excretion. Coinfusion of BK with BKA completely abrogated the renal excretory changes induced by BKA. These data suggest that intrarenal KKS plays a role in control of renal function largely by a tubular mechanism during low sodium intake.


1993 ◽  
Vol 85 (5) ◽  
pp. 607-614 ◽  
Author(s):  
T. C. Li Kam Wa ◽  
S. Freestone ◽  
R. R. Samson ◽  
N. R. Johnson ◽  
M. R. Lee

1. The effects of 1 h intravenous infusions of equimolar amounts (45 nmol min−1 kg−1) of two putative 5-hydroxytryptamine renal prodrugs, 5-hydroxy-L-tryptophan and γ-L-glutamyl-5-hydroxy-L-tryptophan, were investigated in a randomized, placebo-controlled, cross-over study in nine healthy male subjects. 2. Cumulative urinary 5-hydroxytryptamine excretion over the 3 h observation period rose by about 370-fold after 5-hydroxy-L-tryptophan and 390-fold after γ-L-glutamyl-5-hydroxy-L-tryptophan when compared with placebo infusion. Urinary 5-hydroxy-L-tryptophan excretion was three times higher after administration of γ-L-glutamyl-5-hydroxy-L-tryptophan than after 5-hydroxy-L-tryptophan infusion. Urinary 5-hydroxyindole-3-acetic acid excretion after 5-hydroxy-L-tryptophan infusion was significantly greater than that after γ-L-glutamyl-5-hydroxy-L-tryptophan administration. Urinary dopamine excretion was not affected by either compound when compared with placebo. 3. 5-Hydroxy-L-tryptophan significantly reduced urine flow rate and urinary sodium excretion. γ-L-Glutamyl-5-hydroxy-L-tryptophan was antinatriuretic but did not affect urine output. These changes occurred without significant alterations in effective renal plasma flow and glomerular filtration rate. 4. Both 5-hydroxy-L-tryptophan and γ-L-glutamyl-5-hydroxy-L-tryptophan significantly increased plasma aldosterone concentration without a concomitant rise in plasma renin activity. The increase after γ-L-glutamyl-5-hydroxy-L-tryptophan was smaller and delayed. 5-Hydroxy-L-tryptophan, but not γ-glutamyl-5-hydroxy-L-tryptophan, increased serum growth hormone concentration. 5. There was a significant increase in diastolic blood pressure after 5-hydroxy-L-tryptophan administration, but not after γ-L-glutamyl-5-hydroxy-L-rryptophan. 6. These results show that both prodrugs generate 5-hydroxytryptamine. The antinatriuresis after both compounds is presumably mediated by intrarenally generated 5-hydroxytryptamine and this appears to be predominantly a tubular effect. The urinary metabolite data and greater extrarenal effects produced by 5-hydroxy-L-tryptophan indicate that the glutamyl derivative is relatively more selective for the kidney than 5-hydroxy-L-tryptophan.


1990 ◽  
Vol 258 (5) ◽  
pp. H1491-H1497
Author(s):  
S. D. Kivlighn ◽  
T. E. Lohmeier ◽  
H. M. Yang ◽  
Y. Shin

To determine the long-term effects of a physiological dose of atrial natriuretic peptide (ANP) on renin release, the renin response to reductions in renal arterial pressure (RAP) was studied during 1) control conditions and 2) acute and 3) chronic (5 days) intravenous infusion (5 ng.kg-1.min-1) of alpha-human ANP in conscious dogs maintained on a normal sodium intake. Renal perfusion pressure was servo controlled at reduced levels with an inflatable occluder placed around the abdominal aorta just above the renal arteries. Under control conditions, reducing RAP by 30 and 40 mmHg increased plasma renin activity (PRA) 4- to 5- and 9- to 10-fold, respectively. Acute ANP infusion had no significant effect on either basal levels of PRA or the PRA response to reduced RAP. During chronic ANP infusion there was a two- to threefold increment in plasma ANP concentration and approximately a twofold increase in urinary sodium excretion on day 1; however, there were no significant long-term changes in mean arterial pressure, basal PRA, or the levels of PRA achieved during reductions in RAP. These findings indicate that the changes in plasma ANP concentration that occur under normal physiological conditions do not appreciably alter either basal PRA or renin release in response to renal hypotension in conscious sodium-replete dogs studied under resting conditions.


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