Effect of Haemorrhage on Renin Concentration in Superficial and Deep Venous Outflows of the Cat Kidney

1981 ◽  
Vol 60 (6) ◽  
pp. 703-706 ◽  
Author(s):  
Susan M. Jones ◽  
J. Torretti

1. Plasma renin concentration is significantly higher in the subcapsular venous outflow, which drains the superficial cortex, than in the deep venous outflow, which drains the inner half of the cortex and medulla of the cat kidney. The purpose of these experiments was to observe whether this pattern is preserved or disrupted by a stimulus to renin release. 2. Plasma renin concentration in arterial samples and in the superficial and deep renal venous outflows was measured before and after haemorrhage which produced a 24 ± 6.7% drop in mean blood pressure in 13 cats. 3. After haemorrhage, total kidney plasma flow and glomerular filtration rate (GFR) did not change significantly. There was a rise in arterial plasma renin concentration. Venous minus arterial plasma renin concentration increased significantly in the deep venous outflow, but not in the superficial outflow. 4. The results suggest that both superficial and deep cortical venous drainage of the cat kidney should be considered when measuring renal renin release. In addition, they suggest that there may be differences in the response of superficial and deep juxtaglomerular apparatuses to haemorrhage.

1990 ◽  
Vol 259 (4) ◽  
pp. F645-F652 ◽  
Author(s):  
S. Y. Chou ◽  
A. Dahhan ◽  
J. G. Porush

The renal actions of endothelin were examined by infusing it intrarenally in anesthetized dogs at 4 ng.min-1.kg-1 without affecting arterial blood pressure or cardiac output. Endothelin infusion caused a transient and significant increase in renal blood flow (RBF) by 13 +/- 2%, followed by large decreases in RBF and glomerular filtration rate (GFR; by 26 +/- 2 and 23 +/- 7%, respectively) but did not alter urine flow rate or absolute sodium excretion. After endothelin infusion, renal venous and arterial plasma 6-ketoprostaglandin F1 alpha increased from 250 +/- 58 and 117 +/- 31 to 1,044 +/- 249 and 617 +/- 211 pg/ml, respectively, and its renal output increased from 339 +/- 99 to 963 +/- 202 pg.min-1.g-1 (P less than 0.01 for all). The renal prostacyclin synthesis was augmented by endothelin without stimulating the renal renin release or norepinephrine output. Inhibition of prostaglandin synthesis with indomethacin partially prevented the early renal vasodilation induced by endothelin, which then caused a more pronounced decline in RBF and GFR (by 65 +/- 7 and 54 +/- 8%, respectively). With suppression of prostacyclin synthesis, inhibition of renin release by endothelin was observed. Thus the vasoconstrictive effects of endothelin on renal hemodynamics are significantly modified by its ability to enhance production of vasodilators, including prostacyclin.


1970 ◽  
Vol 38 (2) ◽  
pp. 157-174 ◽  
Author(s):  
K. F. Hosie ◽  
J. J. Brown ◽  
A. M. Harper ◽  
A. F. Lever ◽  
R. F. MacAdam ◽  
...  

1. In anaesthetized dogs the rate at which renin was released into the circulation of the right and left kidneys was estimated from renal blood flow, haematocrit, and the V-A renin concentration difference across the kidney. Renin was also measured in samples of renal lymph collected at the same time. 2. The effect on renin release of reducing blood flow in one kidney was studied. For all observations (control and experimental), renal venous plasma renin concentration (RVR) was directly related to arterial plasma renin concentration and to renin release; RVR was inversely related to renal plasma flow. 3. The concentration of renin in renal lymph was considerably higher than that in renal venous plasma taken at the same time. Arterial plasma renin concentration was directly related to the sum of the rates at which renin was released from the two kidneys. 4. Clamping the renal artery of one kidney for 1 hr led to a marked reduction of renal blood flow, to a marked increase in RVR and to a variable change in renin release. Removal of the clamp was followed by increased renin release and by reversal of a previously positive V-A renin difference in the control kidney. 5. On several other occasions negative V-A renin differences were observed. That is, more renin appeared to enter the kidney in arterial blood than left in the renal vein.


1975 ◽  
Vol 48 (2) ◽  
pp. 147-151
Author(s):  
C. S. Sweet ◽  
M. Mandradjieff

1. Renal hypertensive dogs were treated with hydrochlorothiazide (8−2 μmol/kg or 33 μmol/kg daily for 7 days), or timolol (4.6 μmol/kg daily for 4 days), a potent β-adrenergic blocking agent, or combinations of these drugs). Changes in mean arterial blood pressure and plasma renin activity were measured over the treatment period. 2. Neither drug significantly lowered arterial blood pressure when administered alone. Plasma renin activity, which did not change during treatment with timolol, was substantially elevated during treatment with hydrochlorothiazide. 3. When timolol was administered concomitantly with hydrochlorothiazide, plasma renin activity was suppressed and blood pressure was significantly lowered. 4. These observations suggest that compensatory activation of the renin-angiotensin system limits the antihypertensive activity of hydrochlorothiazide in renal hypertensive dogs and suppression of diuretic-induced renin release by timolol unmasks the antihypertensive effect of the diuretic.


1966 ◽  
Vol 35 (4) ◽  
pp. 373-378 ◽  
Author(s):  
J. J. BROWN ◽  
D. L. DAVIES ◽  
P. B. DOAK ◽  
A. F. LEVER ◽  
J. I. S. ROBERTSON

SUMMARY Plasma renin concentration has been measured in normal women at intervals throughout pregnancy. Further measurements have been made in the days and hours before and after delivery of the foetus and placenta. Plasma renin was consistently raised in the majority of pregnant women and did not change markedly until 24 hr. or more after delivery. The significance of these findings is discussed.


1986 ◽  
Vol 250 (4) ◽  
pp. R633-R637
Author(s):  
J. E. Szilagyi ◽  
J. Chelly ◽  
M. F. Doursout

The influence of blockade of endogenous opioids on the release of renin due to partial renal arterial constriction was determined acutely and chronically in unilaterally nephrectomized dogs. In acute preparations changes in plasma renin activity, arterial blood pressure, and heart rate were determined after 15 min of 60% renal arterial constriction before and after administration of either a saline vehicle, the opiate antagonist naloxone (0.05 mg/kg), or morphine (2 mg/kg). Acute antagonism of endogenous opiates abolished the increase in plasma renin activity and mean arterial pressure associated with renal arterial constriction. Repeated renal arterial constrictions in saline- or morphine-treated animals did not alter the humoral or hemodynamic responses. In chronic preparations long-term naloxone infusion attenuated the development of renovascular hypertension and diminished the increase in plasma renin activity. These data suggest that endogenous opioid peptides are modulators in the control of renin release and may be important participants in the pathogenesis of hypertension.


1985 ◽  
Vol 69 (2) ◽  
pp. 207-214 ◽  
Author(s):  
D. P. Worth ◽  
J. N. Harvey ◽  
J. Brown ◽  
M. R. Lee

1. γ-l-Glutamyl-l-dopa was given by intravenous infusion to eight normal subjects at doses of 12.5 and 100 μg min−1 kg−1. 2. Both doses of the dipeptide resulted in an increase in mean urinary sodium excretion. 3. Mean effective renal plasma flow rose at both doses, but mean glomerular filtration rate increased only at the lower dose. 4. There was a fall in mean plasma renin activity after the infusion of both 12.5 and 100 μg min−1kg−1. 5. Mean urine free dopamine excretion increased by 280- and 2500-fold at infusion rates of 12.5 and 100 μg min−1 kg−1 respectively. 6. Mean plasma free dopamine rose at both doses but the increase at 12.5 μg min−1 kg−1 was not to a level previously associated with systemic effects of the catecholamine. 7. On administration of the dipeptide at 12.5 μg min−1 kg−1 there were no changes in blood pressure or heart rate, but at the higher dose there was a fall in diastolic blood pressure. 8. At a dose of 12.5 μg min−1 kg−1 in man, there is kidney specific conversion of gludopa to dopamine.


1980 ◽  
Vol 238 (5) ◽  
pp. F387-F393
Author(s):  
N. Himori ◽  
A. Izumi ◽  
T. Ishimori

Types of beta-adrenoceptors mediating renin release induced by isoproterenol were investigated in conscious dogs. The nonselective beta-adrenoceptor blocking drugs propranolol, D-32, and pindolol significantly inhibited increases in heart rate and plasma renin activity and a fall of blood pressure produced by intravenous infusion of isoproterenol (10 microgram . kg-1 . 20 min-1). d-Propranolol and d-D-32 did not inhibit these three responses to isoproterenol. The selective beta 1-adrenoceptor blocking drug atenolol, at the oral dose of 6 mg/kg, which selectively suppressed isoproterenol-induced tachycardia, significantly inhibited the renin release caused by isoproterenol. By contrast, the renin release induced by isoproterenol was not modified by the selective beta 2-adrenoceptor blocking drug IPS-339 at an oral dose of 3 mg/kg, which fully and selectively antagonized the fall of blood pressure in response to isoproterenol. There was good correlation between suppression of isoproterenol-induced renin release and that of isoproterenol-induced tachycardia after various beta-adrenoceptor blocking drugs. These results lead to the conclusion that in conscious dogs the beta-adrenoceptors mediating release are mainly of the beta 1 type.


1996 ◽  
Vol 271 (1) ◽  
pp. H184-H191
Author(s):  
S. A. Katz ◽  
J. A. Opsahl ◽  
L. M. Forbis ◽  
W. Ayenew

Active renin and five major active renin glycoforms were measured in plasma and the carotid wall of anesthetized rabbits before and after 1.5- and 24-h bilateral nephrectomy (BNX). Before BNX, there was no difference in renin glycoform proportions between plasma and the carotid wall. Plasma renin concentration (PRC) fell by 67% after 1.5-h BNX due to preferential clearance of renin glycoforms I+II, but no significant change in renin concentration was seen in the carotid artery (or aorta). Twenty-four hours after BNX, PRC and carotid wall renin concentrations were reduced by 99.7 and 97.7%, respectively, while the proportion of renin glycoforms I+II in the carotid wall was significantly elevated. These data are consistent with the view that vascular renin is derived from plasma renin of renal origin. After BNX, renin disappearance from the carotid (and aortic wall) is slower than renin decay from plasma, and the less negatively charged active renin glycoforms I+II exit the carotid wall much more slowly than the more negatively charged glycoforms. After 24-h BNX, renin glycoforms I+II were still effluxing from the vascular wall and represented the only glycoforms present in the carotid wall.


1991 ◽  
Vol 260 (4) ◽  
pp. H1031-H1036 ◽  
Author(s):  
K. Hasunuma ◽  
K. Yamada ◽  
Y. Tamura ◽  
S. Yoshida

To investigate the involvement of prostacyclin and the sympathetic nervous system in cardiovascular responses to 1-desamino-8-D-arginine vasopressin (DDAVP), a selective V2-receptor agonist, in normal subjects, DDAVP (0.4 micrograms/kg) was infused with or without indomethacin, a cyclooxygenase inhibitor, or propranolol, a beta-adrenoceptor antagonist. A decrease in blood pressure and increases in pulse rate and plasma renin activity (PRA) were observed by DDAVP infusion. Indomethacin did not influence the DDAVP-induced changes in blood pressure and pulse rate but suppressed the increases in PRA and urinary 6-ketoprostaglandin F1 alpha excretion after DDAVP infusion. Even with propranolol administration, DDAVP produced a similar decrease in blood pressure with a reduction of the increased pulse rate. The DDAVP-induced increase in PRA was not affected either. Indomethacin or propranolol alone did not affect the basal levels of the parameters. DDAVP stimulated the in vitro renin release from rabbit renal cortical slices. The stimulation was inhibited by indomethacin or d(CH2)5[D-Ile2,Ile4]AVP, a selective V2-receptor antagonist. These findings suggest that DDAVP primarily elicits vasodilation, probably through the prostacyclin-independent endothelium-derived relaxation and DDAVP also causes an increase in renin release, which would be partly attributed to the increased synthesis of prostacyclin due to vasculoendothelial V2-like receptor activation but not mainly due to an increase in sympathetic nerve activity.


1985 ◽  
Vol 249 (4) ◽  
pp. F596-F602
Author(s):  
W. J. Welch ◽  
C. E. Ott ◽  
G. P. Guthrie ◽  
T. A. Kotchen

Renin release is increased in the adrenalectomized rat and is not inhibited by sodium chloride administration. The purpose of this study was to determine whether increased renin release is related to impaired absorptive chloride transport in the loop of Henle. Chloride transport in the loop was measured before and after acute saline infusion in three groups of rats: 1) saline-drinking adrenalectomized rats (Adx); 2) saline-drinking dexamethasone-treated adrenalectomized rats (Dex); and 3) water-drinking sham-operated controls. Unrelated to differences of arterial pressure, glomerular filtration rate, or net sodium chloride balance, chloride reabsorption in the loop of Henle of Adx [836 +/- 172 peq/min (SE)] was less (P less than 0.01) than in controls (1,646 +/- 353) and Dex (1,377 +/- 318) before saline infusion. After saline infusion, chloride delivery to the loop increased (P less than 0.05) in all three groups. However, loop chloride reabsorption increased (P less than 0.01) only in controls and Dex but not in Adx. Before saline infusion, plasma renin concentration (PRC) of Adx (350 +/- 108 U/ml) was greater (P less than 0.01) than that in controls (56 +/- 6) or Dex (108 +/- 36); sodium chloride infusion failed to inhibit PRC in Adx, whereas PRC was suppressed (P less than 0.01) by saline in Dex and controls. Thus stimulation of renin release in adrenalectomized animals was associated with decreased absorptive chloride transport in the loop of Henle. Dexamethasone normalized loop function and renin responsiveness to sodium chloride.


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