Renal turnover of the extracellular fluid compartment in humans and mosquitoes
| Basic renal mechanism . | Humans: Glomerular filtration and tubular reabsorption . | Mosquitoes: Tubular secretion and reabsorption . |
|---|---|---|
| Body mass | 70 kg | 1.3 mga |
| Extracellular fluid volume(ECV)b | 14 liters | 0.39 μl |
| Number of renal functional units | 2.4×106,c | 5d |
| Presentation rate (PR) of ECV to renal epithelia for homeostatic adjustments | 180 1 day−1,e | 3.7−78.3 μl day−1,f |
| Daily renal turnover of ECV (PR/ECV) | 12.8 | 9.5−200 |
| Fluid transport, isolated renal unit normalized to a tubule length of 1 mm | 0.4−4 nl min−1 mm−1 | 0.3−1.9 nl min−1 |
| reabsorptiong | mm−1secretionh |
| Basic renal mechanism . | Humans: Glomerular filtration and tubular reabsorption . | Mosquitoes: Tubular secretion and reabsorption . |
|---|---|---|
| Body mass | 70 kg | 1.3 mga |
| Extracellular fluid volume(ECV)b | 14 liters | 0.39 μl |
| Number of renal functional units | 2.4×106,c | 5d |
| Presentation rate (PR) of ECV to renal epithelia for homeostatic adjustments | 180 1 day−1,e | 3.7−78.3 μl day−1,f |
| Daily renal turnover of ECV (PR/ECV) | 12.8 | 9.5−200 |
| Fluid transport, isolated renal unit normalized to a tubule length of 1 mm | 0.4−4 nl min−1 mm−1 | 0.3−1.9 nl min−1 |
| reabsorptiong | mm−1secretionh |
Female yellow fever mosquito (Aedes aegypti) maintained in the laboratory of Beyenbach.
Extracellular volume is 20% and 30% of body mass in man and mosquito,respectively.
Glomerular renal tubules in both kidneys.
Malpighian tubules in A. aegypti.
Glomerular filtration rate.
Urine flow rate from the rectum of blood-fed A. aegypti during late and peak phases of diuresis. These are minimum epithelial secretion rates since there is no glomerular filtration. Data from Williams et al.(1983).
Rate of transepithelial fluid absorption in rabbit and rat renal proximal tubules.
Fluid secretion rates in distal segments of Malpighian tubules of female A. aegypti. Data from Beyenbach(1995). Maximum fluid secretion rates have not yet been determined but are expected to exceed 10 nl min−1 mm−1 in view of a urine flow rate of 78.3 μl day−1 at peak diuresis in the intact insect (see PR above).