Exam 2 Net Filtration Pressures

Question 1

Gbhp

Answer 1

Glomerular blood hydrostatic pressure
Pressure leaving the glomerulus towards the Bowman’s capsule
Typically 55 mmhg

Question 2

Chp

Answer 2

Colloid hydrostatic pressure
An opposing Force to the gbhp
Created by the water already in the Bowman’s capsule pushing back toward the glomerulus

Question 3

Bcop

Answer 3

Blood colloid osmotic pressure
An opposing Force to the gbhp
30 mmhg
Proteins in blood of the glomerulus try to prevent the loss of fluid into the Bowman’s capsule

Question 4

Gfr definition and amounts

Answer 4

Glomerular filtration rate
The amount of filtrate from the Bowman’s capsule of both kidneys in 1 minute
In males, roughly 125 ml per minute
In females 105 ml per minute

Question 5

What affects the GFR?

Answer 5

Any change in filtration pressure

Question 6

Three things to control the GFR

Answer 6

Auto regulation
Neural regulation
Hormonal regulation

Question 7

Auto regulation if BP is too high
Fixes it in 2 ways

Answer 7

1. smooth muscle contractile cells in the afferent arteriole contract reduce BP
2. Cells of the macula densa inhibit the release of the hormone NO. Which allow the afferent arterioles to constrict?

This decreases the pressure and flow into the glomerulus

Question 8

Neural regulation

Answer 8

Vessels of the kidneys have a sympathetic nerve supply that causes vasoconstriction

At rest stimulation is low and vessels are dilated
Kidneys are on autoregulation

During exercise or hemorrhage stimulation causes vasoconstriction of the afferent arterioles and the GFR decreases

Question 9

Fight or flight with neural regulation of the kidneys

What happens to the GFR?

What happens to urine output

Answer 9

GFR decreases

Decreases urine output which conserves water and sends blood to essential areas such as skeletal muscle

Question 10

Raa complex begins with a drop in blood pressure

Answer 10

Kidneys release renin
Converts blood protein angiotensinogen into A1
A1 travels in the blood to the lungs
Lungs release Ace
Ace converts A1 into A2
A2 vasoconstricts vessels and causes the release of aldosterone from the adrenal gland which causes the kidneys to retain sodium and thus water

Both the vasoconstriction of the vessels and the retention of sodium causes a raise in BP

Question 11

Two ways the RAA complex raises BP

Answer 11

A2 vasoconstricts vessels increasing BP
Aldosterone raises BP by retaining sodium in this water

Question 12

Hormone anp function

Answer 12

Atrial natiuretic peptide
Made in the heart
Controls levels of sodium

High BP
Heart releases ANP
Targets kidneys to excrete na in fluids
Lower blood volume equals lower BP