This section calculates the control of atrial natriuretic peptide secretion by the
left and right atria of the heart. It also calculates a multiplier factor for
controlling the resistance of the afferent arterioles (AAR) of the kidneys.
Encapsulation grouping component containing all the components in the Atrial Natriuretic Peptide Model.
The inputs and outputs of the Atrial Natriuretic Peptide Model must be passed by this component.
ANP1, ANP2, ANP3, ANP3A, and ANP4:
Calculation of the total amount of atrial natriuretic peptide secreted at
any given time. Block ANP1 determines the pressure level at which changes
in left atrial pressure (PLA) will begin to affect atrinatriuretic peptide
secretion. Block 1A sets a lower limit of zero for this secretion.
Block ANP2 calculates from the pressure level in the right atrium (PRA) the
stimulation of ANP output by the right atrium. Block 3 multiplies the
output of the right atrium by two-fold (against a one-fold amount secreted
by the left atrium). Block 3A sets a lower limit of zero for right atrial
output. Block 4 adds the outputs from the left atrium and right atrium.
ANP5:
Block 5 normalizes the ANP secretion under normal conditions to a value of 1.
ANP1, ANP2, ANP3 and ANP3A:
Calculation of the total amount of atrial natriuretic peptide secreted at
any given time. Block ANP1 determines the pressure level at which changes
in left atrial pressure (PLA) will begin to affect atrinatriuretic peptide
secretion. Block 1A sets a lower limit of zero for this secretion.
Block ANP2 calculates from the pressure level in the right atrium (PRA) the
stimulation of ANP output by the right atrium. Block 3 multiplies the
output of the right atrium by two-fold (against a one-fold amount secreted
by the left atrium). Block 3A sets a lower limit of zero for right atrial
output.
ANP1, ANP2, ANP3 and ANP3A:
Calculation of the total amount of atrial natriuretic peptide secreted at
any given time. Block ANP1 determines the pressure level at which changes
in left atrial pressure (PLA) will begin to affect atrinatriuretic peptide
secretion. Block 1A sets a lower limit of zero for this secretion.
Block ANP2 calculates from the pressure level in the right atrium (PRA) the
stimulation of ANP output by the right atrium. Block 3 multiplies the
output of the right atrium by two-fold (against a one-fold amount secreted
by the left atrium). Block 3A sets a lower limit of zero for right atrial
output.
ANP4 and ANP5:
Block 4 adds the outputs from the left atrium and right atrium. Block 5 normalizes
the ANP secretion under normal conditions to a value of 1.
$\mathrm{ANPL}=\begin{cases}0 & \text{if $(\mathrm{PLA}-1)\times 1< 0$}\\ (\mathrm{PLA}-1)\times 1 & \text{otherwise}\end{cases}\mathrm{ANPR2}=\begin{cases}0 & \text{if $(\mathrm{PRA}+1)\times 2< 0$}\\ (\mathrm{PRA}+1)\times 2 & \text{otherwise}\end{cases}\mathrm{ANP}=\frac{\mathrm{ANPL}+\mathrm{ANPR2}}{3}$
ANP 7:
This block allows infusion of ANP into the circulation (ANPINF). The output
of the block is ANP1 which is the total rate of ANP entering the circulation
at any given time.
ANP 7:
This block allows infusion of ANP into the circulation (ANPINF). The output
of the block is ANP1 which is the total rate of ANP entering the circulation
at any given time.
$\mathrm{ANP1}=\begin{cases}\mathrm{ANPKNS} & \text{if $\mathrm{ANPKNS}> 0$}\\ \mathrm{ANP}+\mathrm{ANPINF} & \text{otherwise}\end{cases}$
ANP8, ANP9, and ANP10:
Calculation of the concentration of ANP in the plasma (ANPC) from the rate of
entry of ANP into the plasma (ANP1). The time constant for build-up of ANP in
the circulation is determined by ANPTC in Block 9. ANPC is normalized to 1.
ANP8, ANP9, and ANP10:
Calculation of the concentration of ANP in the plasma (ANPC) from the rate of
entry of ANP into the plasma (ANP1). The time constant for build-up of ANP in
the circulation is determined by ANPTC in Block 9. ANPC is normalized to 1.
$\frac{d \mathrm{ANPC}}{d \mathrm{time}}=\frac{\mathrm{ANP1}-\mathrm{ANPC}}{\mathrm{ANPTC}}$
ANP11:
This curve calculates a multiplier factor (ANPX) for determining the effect
of ANP on the afferent arteriolar resistance of the kidneys. The upper limit
of ANPX is ANPXUL.
ANP 12:
This block sets the lower limit of ANPX equal to -1.
ANP11:
This curve calculates a multiplier factor (ANPX) for determining the effect
of ANP on the afferent arteriolar resistance of the kidneys. The upper limit
of ANPX is ANPXUL.
ANP 12:
This block sets the lower limit of ANPX equal to -1.
$\mathrm{ANPX1}=\mathrm{ANPXUL}-\frac{\mathrm{ANPXUL}}{0.5555556(1+\mathrm{ANPC})}\mathrm{ANPX}=\begin{cases}-1 & \text{if $\mathrm{ANPX1}< -1$}\\ \mathrm{ANPX1} & \text{otherwise}\end{cases}$