SECRETION AND REABSORPTION: The Loop of Henle

Tubular fluid flows in _______ directions in the descending and ascending limbs (descending limb fluid travels toward _______ and the ascending limb fluid travels toward the _____).

opposite, medulla, cortex

Tubular ____ flows in opposite directions from the ____ in the vasa recta.

fluid, blood

The NKCC pump transport mechanism occurs in the _____ _________ limb of the Loop of Henle.

thick, ascending

In the thick ascending limb water does not follow via ______ since this part of the Loop is _________ to water.

osmosis, impermeable

What solutes are moving out of the tubular fluid in the thick ascending limb?

1) Sodium 2) potassium 3) chloride

NKCC transport mechanism (1): sodium, potassium, and chloride all move into the epithelial cell through a _______ mechanism; both ______ and _______ move against their concentration gradient.

symport, potassium, chloride

NKCC transport mechanism (2): When chloride moves into the epithelial cell from the symport mechanism at the apical surface then ______ down its concentration gradient into the interstitial fluid.

diffuses

NKCC transport mechanism (3): Potassium is pumped back into the cell by the ______ - ________ ATPase at the basolateral surface; they can then exit through ____ channels at the apical surface.

sodium, potassium, leak

NKCC transport mechanism (4): The net result of this transport mechanism is the reabsorption of ______ and _______ while ________ is returned to the tubular fluid.

sodium, chloride, potassium

Since interstitial fluid is more _______ than fluid in the tubule lumen this promotes the movement of cations through ____________ transport into the interstitial fluid and then the plasma of the peritubular capillaries/vasa recta.

negative, paracellular

Since the thick ascending limb is impermeable to water it does NOT follow the NKCC pump by ______.

osmosis