Key result
Large protein fraction from volume-expanded rats drives significantly greater natriuresis versus control plasma.
Effect estimate: peak differences of 4 and 3.5 μequiv./min per gram kidney weight
Vascular expansion in rats generates a humoral factor, likely a protein or protein-bound moiety, that significantly increases sodium excretion.
Suggests a high-MW natriuretic factor in volume-expanded rats; leaves open its identity and human relevance.
Plasma was obtained by an isovolaemic exchange procedure from rats undergoing sustained blood volume expansion (experimental) and from normovolaemic but otherwise similarly prepared rats (control). Four plasma fractions, showing absorption at 280 nm, were separated by G-50 Sephadex gel filtration, freeze dried and reconstituted for assay in hydropaenic rats for natriuretic activity. Only the large protein fraction (molecular weight exceeding 30 000) of experimental plasma produced a significantly greater natriuresis than the corresponding fraction from either control plasma or a fractionated 5.6% albumin solution. The respective averaged peak differences in sodium excretion were 4 and 3.5 μequiv./min per gram kidney weight. This additional natriuretic activity was attributed to a humoral factor, either a protein or a protein-bound moiety, generated by vascular expansion.
No takes yet. Share an insight, caveat, or question.
Pearce et al. (1975) studied Volume expansion. Plasma from volume-expanded rats (large protein fraction) vs. Plasma from normovolaemic rats or 5.6% albumin solution was evaluated on Natriuresis (sodium excretion) (peak differences of 4 and 3.5 μequiv./min per gram kidney weight). The large protein fraction of plasma from volume-expanded rats produced significantly greater natriuresis than control plasma, with peak differences in sodium excretion of 4 and 3.5 μequiv./min/g.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: