Renal interstitial fluid angiotensin. Modulation by anesthesia, epinephrine, sodium depletion, and renin inhibition.
Using a microdialysis technique, we monitored changes in right and left renal interstitial fluid angiotensins in anesthetized and conscious dogs (both n = 5) in response to right renal interstitial epinephrine (0.2 mg/kg per minute) administration. Renal interstitial and plasma angiotensin levels also were monitored in conscious dogs (n = 4) in response to dietary sodium deprivation (10 mmol/d) for 5 consecutive days. Changes in renal interstitial and plasma angiotensins in response to interstitial administration of a specific renin inhibitor, ACRIP (0.5 micrograms/kg per minute for 20 minutes), were monitored on day 5 of sodium depletion. At basal levels, there were no significant differences between the right and left renal interstitial immunoreactive angiotensin levels in anesthetized dogs. Renal interstitial epinephrine administration caused a significant increase in renal interstitial immunoreactive angiotensin concentrations in both anesthetized and conscious dogs (P < .01). However, anesthetized dogs had significantly higher renal interstitial immunoreactive angiotensin levels basally and in response to epinephrine than conscious dogs (P < .05). Renal interstitial immunoreactive angiotensin concentrations increased significantly and progressively during exposure to a low sodium diet from 3.9 +/- 1 nmol on day 1 to 740 +/- 332 nmol on day 5 (P < .01). Renal interstitial immunoreactive angiotensin decreased significantly to 124 +/- 37 nmol (P < .01) in response to intrarenal renin inhibition at the end of day 5 of sodium depletion. Plasma immunoreactive angiotensin increased significantly (P < .01) in response to sodium depletion, and no change occurred during intrarenal renin inhibition.(ABSTRACT TRUNCATED AT 250 WORDS)
Siragy
H M
HM
Department of Internal Medicine, University of Virginia, Charlottesville, USA.
Howell
N L
NL
Ragsdale
N V
NV
Carey
R M
RM
D000758:Anesthesia; D000809:Angiotensins / Q000032:analysis*; D000818:Animals; D004285:Dogs; D004837:Epinephrine / Q000494:pharmacology*; D005110:Extracellular Space / Q000737:chemistry*; D007668:Kidney / Q000737:chemistry*; D017551:Microdialysis; D012964:Sodium / Q000172:deficiency*; D000092502:Renin Inhibitors
D000809:Angiotensins; D004837:Epinephrine; D012964:Sodium; D000092502:Renin Inhibitors