The APS Journal Legacy Content is the corpus of 100 years of historical scientific research from the American Physiological Society research journals. This package goes back to the first issue of each of the APS journals including the American Journal of Physiology, first published in 1898. The full text scanned images of the printed pages are easily searchable. Downloads quickly in PDF format.

SUMMARY1. The effect on renal Na and water excretion of increasing the NaCl concentration of blood supplying the brain was investigated in conscious water-loaded sheep. Intracarotid infusion of 4 m-NaCl at 0-8 ml./min for 60 min was compared with equivalent intrajugular infusion.2. A more rapid increase in renal Na excretion and urine osmolality occurred with the intracarotid infusions than with intrajugular infusions.3. Intracarotid infusions of 2 M sucrose or fructose at 1-6 ml./min for 30 min compared with equivalent intrajugular infusions also caused a greater increase in renal Na excretion, urine osmolality and a decrease in urine flow rate.4. The results suggest that there are receptors in the brain sensitive to changes in extracellular tonicity which influence renal Na excretion. It is possible that changes in ADH secretion alone mediate the early natriuresis seen with intracarotid hypertonic infusions although an alternative concurrent mechanism cannot be ruled out.

Intrarenal infusion of the natural prostaglandin PGE2 increases renal blood flow, renal interstitial hydrostatic pressure, and urinary sodium excretion. A newly synthesized prostaglandin analogue, 4-3-[3-[2-(1-hydroxycyclohexyl)- ethyl]-4-oxo-2-thiazolidinyl]propyl benzoic acid, increases renal blood flow without increasing sodium excretion. To investigate the role of renal interstitial hydrostatic pressure in this dissociation, comparisons were made between PGE2 and the prostaglandin analogue. Intrarenal infusion of PGE2 increased renal blood flow, renal interstitial hydrostatic pressure, and urinary sodium excretion. Following a similar increase in renal blood flow with intrarenal infusion of prostaglandin analogue, renal interstitial hydrostatic pressure and urinary sodium excretion were not changed. To determine whether increases in urinary sodium excretion due to PGE2 infusion are causally related to the increase in renal interstitial hydrostatic pressure rather than to the increase in renal blood flow, responses to PGE2 were obtained in the absence of increases in interstitial pressure. When renal interstitial hydrostatic pressure was held constant, urinary sodium excretion did not change although there was a marked increase in renal blood flow. We conclude that increased renal interstitial hydrostatic pressure is necessary to produce an increase in urinary sodium excretion with prostaglandin-mediated renal vasodilation.

No abstract

The APS Journal Legacy Content is the corpus of 100 years of historical scientific research from the American Physiological Society research journals. This package goes back to the first issue of each of the APS journals including the American Journal of Physiology, first published in 1898. The full text scanned images of the printed pages are easily searchable. Downloads quickly in PDF format.

The kinetics of atrial natriuretic peptides (ANP) and the kinetic profile of their effect on blood pressure and renal hemodynamic and electrolyte excretion were investigated in 20 salt-loaded healthy volunteers during and after constant rate infusion. At steady state, mean plasma concentrations of ANP were measured at 210, 430, and 2990 pg/ml and mean systemic clearance was 2.6, 2.5, and 1.7 L/min for ANP infusion rates of 0.5, 1, and 5 micrograms/min, respectively, which corresponds to the clearance rate of other vasoactive peptide hormones. The apparent volume of distribution averaged 17 L and the mean half-life was 4.5 minutes. ANP induced dose-related effects on systemic and renal hemodynamic, as well as urinary electrolyte excretion, albeit with a time lag between onset and full effect.

No abstract