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Resetting protects efficiency of tubuloglomerular feedback

1998; Elsevier BV; Volume: 54; Linguagem: Inglês

10.1046/j.1523-1755.1998.06713.x

1523-1755

Scott C. Thomson, Volker Vallon, Roland C. Blantz,

Marine Biology and Environmental Chemistry

Resetting protects efficiency of tubuloglomerular feedback. Tubuloglomerular feedback (TGF) may effect long-term protection of total body salt and water or may govern minute-to-minute autoregulation of renal function. The task for which TGF is best suited depends on the orientation of ambient tubular flow relative to the inflection point of the TGF curve and on the tendency of TGF to reset in response to prolonged stimulation. Current data suggest that the TGF curve is coupled closely to ambient flow in individual nephrons such that the system is capable of compensating both negative and positive perturbations in tubular flow. This coupling is mediated by events within the juxtaglomerular apparatus that cause the TGF curve to reset laterally in response to sustained shifts in tubular flow. This resetting of TGF occurs within 30 to 60minutes of an applied stimulus, suggesting that TGF is better suited to mediate dynamic autoregulation than to account for sustained vasoconstriction during proximal tubular injury.