Glomerular filtration rate (GFR), urine flow (UV), renal tubular transport maximum for glucose (TMG) and single nephron glomerular filtration rate (SNGFR), determined in anesthetized norepinephrine-infused trout (Salmo gairdneri), were 18.51 ± 5.78 μl.min-1.kg body wt-1, 5.31 ± 1.38 μl.min-1.kg body wt-1, 105.21 ± 46.84 μg.min-1.kg body wt-1, and 3.74 ± 1.12 nl/min, respectively, when in seawater (SW) and 140.39 ± 17.24, 76.38 ± 10.41, 626.16 ± 77.46, and 1.31 ± 0.20 in freshwater (FW). Angiotensin II infusions, to reduce UV, GFR, and TMG by 50%, had no effect on the average SNGFR of FW trout, but reduced that of SW fish to 1.42 ± 0.19 nl/min. Infusion of 20% ferrocyanide, visualized as Prussian blue (PB), identified three glomerular populations: filtering (F) with PB in glomerular vessels and tubular lumen; nonfiltering (MF) - PB in glomerular vessels only; nonperfused (MP) - no PB associated with the nephron. SW and FW kidneys contained about 40% NF tubules. In FW, 45% were F tubules compared with 5% in SW, whereas NP tubules comprised 51% of SW tubules and 13% of FW. During angiotensin II infusions the distributions were 9% F and 46% NF in FW and 6% F and 12% NF in SW trout.
|Journal||American Journal of Physiology - Regulatory Integrative and Comparative Physiology|
|State||Published - 1980|
ASJC Scopus subject areas
- Physiology (medical)