Renal Blood Flow and GFR

tohobajo's version from 2017-06-23 08:34

Section 1

Question Answer
What inhibits secretion of renin and ADH?ANP
What decreases Na reabsorption in the late distal tubule and collecting ducts?ANP
What causes vasodilation of afferent A. and vasoconstriction of efferent A?ANP
What increases RBF and GFR?ANP
What vasoaction does Epinephrine have?Vasoconstriction, released by cromaffin cells of adrenal medulla
What vasoaction does Dopamine have?Vasoconstriction
What vasoactin do endothelins have?Vasoconstriction, acts locally to stimulate release of AII, epinephrine and high does ADH
What vasoaction do leukotrienes have?Vasoconstriction, local effects and release is stimulated by inflammation
What vasoaction do prostaglandins have?Vasodilation, prevents/modulates excessive vasoconstriction
What vasoaction does Nitric Oxide have?Vasodilation, produced by the endothelial cells
At low doses, what vasoaction does Dopamine have?Vasodilation
What is the main effect of ADH?Increased water reabsorption
Does ADH affect RBF or GFR?No
What decreases blood flow to the renal medulla, maintaining its hypertonicity essential for concentrating urine?ADH
In severe decreases in effective circulating volume, what produces systemic vasoconstriction?ADH
What decreases RBF and GFR and increases FF?Renin-angiotensin-aldosterone axis
What is the dominant effect of RAAS?Afferent and more pronounced Efferent Vasoconstriction
A small increase in sympathetic nerve activity does what?Augments renin and aldosterone release and results in preferential Efferent vasoconstriction
A strong stimulation of sympathetic nerves does what?Markedly increases both AA and EA resistances and results in drastic decreases in RBF and GFR.
What inhibits Na reabsorption in respose to an increase in ECFV?OLF (Ouabain-Like Factor)

Section 2

Question Answer
What is the mechanism of autoregulation?Afferent arteriole resistance increases as blood pressure goes up
Constriction of only the Afferent arteriole does what to GFR, RPF, and Pgc?Decreases GFR, Decreases RPF, and Decreases Pgc
Constriction of only Efferent arteriole does what to GFR, RPF, and Pgc?First Increases then Decreases GFR, Decreases RPF, and Increases Pgc
Increase in FF does what to the oncotic pressure in PT capillaries?Increases it, leading to higher PT absorption
Decrease in FF does what to oncotic pressure in PT capillaries?Decreases it, leading to decrease in PT absorption
A low glomerular plasma flow means what?Low GFR. Less RBF = Less Filtrate. Oncotic pressure rises quickly and you get to the filtration equilibrium sooner, less filtrate.
A high glomerular plasma flow means what?High GFR. Increase RBF = Increase GFR, the oncotic pressure rises slower and you get more filtrate
Which two starling forces favor ultrafiltration?Pgc and Oncotic pressure of Bowman's space