Acute Effect of Passive Heymann Nephritis on Renal Blood Flow and Glomerular Filtration Rate in the Rat: Role of the Anaphylatoxin C5a and the Alpha-Adrenergic Nervous System

1. In anaesthetized cats, reversible nenal nerve denervation (cooling of the renal nerves on one side at 4°C for 16 min) was performed and its effects on haemodynamic and excretory functions of the ipsilateral and the contralateral kidneys were studied. 2. Renal nerve cooling did not cause any change in arterial pressure. Slight increase in blood flow, no change in glomerular filtration rate and a large increase in water and sodium excretion occurred in the ipsilateral kidney; simultaneously, no change in blood flow, a slight and transient decrease in glomerular filtration rate, and a significant decrease in diuresis and natriuresis were observed in the contralateral kidney. 3. Ipsilateral and contralateral renal changes were equally evident in the early (minutes 0 to 8) and late phases (minutes 8 to 16) of the cooling period. 4. When renal nerve cooling was repeated after surgical denervation of the contralateral kidney all contralateral effects were abolished.

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Serum cystatin is not a marker of glomerular filtration rate in pregnancy

Obstetric Medicine ◽

10.1258/om.2009.090019 ◽

2009 ◽

Vol 2 (3) ◽

pp. 121-122 ◽

Cited By ~ 2

Author(s):

Kate Bramham ◽

David Makanjuola ◽

Wael Hussein ◽

Debra Cafful ◽

Hassan Shehata

Keyword(s):

Glomerular Filtration Rate ◽

Observational Study ◽

Glomerular Filtration ◽

Filtration Rate ◽

Prospective Observational Study ◽

Second Trimester ◽

Third Trimester ◽

Serum Cystatin ◽

In Pregnancy

The role of cystatin C (Cys-C) as a marker of glomerular filtration rate (GFR) in pregnancy is undetermined. Measurements of Cys-C and creatinine (Cr) were taken at 14–17+6, 18–23+6, 27–31+6 weeks' gestation, at delivery and 2–6 weeks postpartum in a prospective observational study of 27 women. There was no difference between Cys-C levels in early and late second trimester, but they were significantly higher in early third trimester ( P < 0.001) than second trimester, despite no concurrent increase in Cr. Cys-C was also significantly higher at delivery than at all other times in pregnancy ( P < 0.001) and fell to postpartum values higher than second trimester measurements ( P < 0.01), but lower than delivery ( P<0.001). In conclusion, changes in Cys-C may be influenced by pregnancy-related changes in glomerular filtration and therefore we would advise against their use as a marker of GFR in pregnancy.

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Renal glomerular filtration rate and hepatic blood flow during voluntary diving in Weddell seals

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1983.245.5.r743 ◽

1983 ◽

Vol 245 (5) ◽

pp. R743-R748 ◽

Cited By ~ 10

Author(s):

R. W. Davis ◽

M. A. Castellini ◽

G. L. Kooyman ◽

R. Maue

Keyword(s):

Blood Flow ◽

Glomerular Filtration Rate ◽

Glomerular Filtration ◽

Hepatic Blood Flow ◽

Filtration Rate ◽

Hepatic Function ◽

Inulin Clearance ◽

Weddell Seals ◽

Icg Clearance ◽

The Mean

Renal and hepatic function were studied during voluntary dives in Weddell seals by measuring the clearance rate of inulin and indocyanine green (ICG). Inulin is cleared exclusively by the kidneys and measures renal glomerular filtration rate (GFR). ICG is cleared by the liver and is blood flow dependent at concentrations used. Studies were conducted from a portable hut with a trapdoor placed over an isolated hole in the sea ice near McMurdo Station, Antarctica. An intravertebral extradural catheter was inserted percutaneously under light anesthesia in subadult seals weighing 130-200 kg. When released into the ice hole, the seals made voluntary dives, but always had to return to breathe. Serial blood samples were taken after single injections of inulin and ICG and analyzed within 24 h. The mean half time (t 1/2) for inulin clearance while resting at the surface was 27.3 +/- 13.0 min (n = 43) and the mean t 1/2 for ICG clearance was 18.3 +/- 7.3 min (n = 23). The mean resting GFR was 3.6 ml X min-1 X kg-1 (range 3.2-3.9, n = 3). Inulin and ICG clearance rates did not change from resting levels during dives shorter than the seal's aerobic dive limit (ADL). Inulin clearance decreased over 90% during dives longer than the ADL, but there was no significant reduction in ICG clearance during dives lasting up to 23 min. It appears that normal renal GFR and hepatic blood flow continue during natural aerobic dives. During dives that exceed the ADL, GFR is reduced but hepatic blood flow may be maintained.

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