thirst, drinking and salt appetite
cardiovascular circulation
organ systems
physiology
Guyton
keyword
TS1, TS1A, TS2, TS2A, TS2B, TS2C, TS3, and TS4:
These are curve-fitting blocks to derive a value for salt appetite and for partial control of
thirst (STH) based on the input values of PO2 in the non-muscle tissue cells (POT) and the
angiotensin multiplier effect (ANM). The constant ANMSLT sets the sensitivity of salt appetite
to angiotensin, and the constant Z10 sets the PO2 level below which POT exerts its effects.
thirst, drinking and salt appetite
organ systems
physiology
cardiovascular circulation
Guyton
This is the CellML 1.1 "parent" file to test the Thirst, Drinking and Salt Appetite Model.
Description of guyton thirst, drinking and salt appetite module
Thirst, Drinking and Salt Appetite
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TS1, TS1A, TS2, TS2A, TS2B, TS2C, TS3, and TS4:
These are curve-fitting blocks to derive a value for salt appetite and for partial control of
thirst (STH) based on the input values of PO2 in the non-muscle tissue cells (POT) and the
angiotensin multiplier effect (ANM). The constant ANMSLT sets the sensitivity of salt appetite
to angiotensin, and the constant Z10 sets the PO2 level below which POT exerts its effects.
keyword
TS9:
Block TS9 sets a lower limit to AHTH equal to zero.
Guyton
Thirst, Drinking and Salt Appetite
TS10 and TS11:
Calculation of the drive to stimulate thirst caused by angiotensin (ANMH) from
the generalized angiotensin multiplier (ANM). The sensitivity of this calculation
is controlled by the angiotensin-thirst sensitivity control variable (ANMTM).
TS1, TS1A, TS2, TS2A, TS2B, TS2C, TS3, and TS4:
These are curve-fitting blocks to derive a value for salt appetite and for partial control of
thirst (STH) based on the input values of PO2 in the non-muscle tissue cells (POT) and the
angiotensin multiplier effect (ANM). The constant ANMSLT sets the sensitivity of salt appetite
to angiotensin, and the constant Z10 sets the PO2 level below which POT exerts its effects.
TS12:
A temporary calculation for rate of intake of fluid by the body (TVZ) is equal to the
drinking drive (AHTH) caused by the product of the salt appetite drive (STH) and the
antidiuretic-thirst drive (AHTH), plus the angiotensin-thirst drive (ANMTH).
Component to set all input values to 1.0 or a prescribed value.
2008-00-00 00:00
Description of guyton thirst, drinking and salt appetite module
TS5, TS6, and TS7:
These blocks are a sensitivity controller for calculating a multiplier effect
of antidiuretic hormone on thirst (AHCM) from an antidiuretic hormone
concentration factor in the circulating body fluids (ADHC). The sensitivity is
controlled by the control factor (AHTHM).
Guyton
TS1, TS1A, TS2, TS2A, TS2B, TS2C, TS3, and TS4:
These are curve-fitting blocks to derive a value for salt appetite and for partial control of
thirst (STH) based on the input values of PO2 in the non-muscle tissue cells (POT) and the
angiotensin multiplier effect (ANM). The constant ANMSLT sets the sensitivity of salt appetite
to angiotensin, and the constant Z10 sets the PO2 level below which POT exerts its effects.
TS5, TS6, and TS7:
These blocks are a sensitivity controller for calculating a multiplier effect
of antidiuretic hormone on thirst (AHCM) from an antidiuretic hormone
concentration factor in the circulating body fluids (ADHC). The sensitivity is
controlled by the control factor (AHTHM).
The salt appetite is considered in this model to be related to the adequacy
of body metabolism, as measured by the PO2 level in the non-muscle tissue
cells (POT). Also, when the concentration of angiotensin increases (ANM),
this, too, increases salt intake. For instance, in circulatory shock, when
the adequacy of metabolism falls, the person develops a salt appetite. For
lack of information, no control function of salt concentration per se has
been assumed, merely that when the body salt falls, circulatory effectiveness
falls, angiotensin increases, and a salt appetite develops.
Three separate factors are assumed to drive the thirst mechanism, the
concentration of antidiuretic hormone, which in turn is driven by changes
in electrolyte composition (as detailed in another section) and second, the
effect of angiotensin on thirst, and third, the effect of the salt appetite
stimulation on thirst.
TS14, TS15, and TS16:
This is a delay circuit which causes the actual rate of fluid intake (TVD) to be delayed
with respect to changes in the temporarily calculated rate of fluid intake (TVZ) by a
time constant TVDLL. Also shown in Block TS14 is a variable (DR) that can be used for
forced input of water over and above the natural drinking desires; this can be used for
intravenous infusion of water as well.
TS10 and TS11:
Calculation of the drive to stimulate thirst caused by angiotensin (ANMH) from
the generalized angiotensin multiplier (ANM). The sensitivity of this calculation
is controlled by the angiotensin-thirst sensitivity control variable (ANMTM).
2008-00-00 00:00
T S 8 a n d T S 9 :
C a l c u l a t i o n o f a t h i r s t d r i v e ( A H T H ) b a s e d o n a n t i d i u r e t i c h o r m o n e a n d s a l t
a p p e t i t e b y m u l t i p l y i n g t h r e e f a c t o r s , t h e s a l t a p p e t i t e d r i v e ( S T H ) , t h e a n t i d i u r e t i c
h o r m o n e c o n c e n t r a t i o n m u l t i p l i e r ( A H C M ) , a n d a c o n s t a n t . B l o c k T S 9 s e t s a l o w e r l i m i t
t o A H T H e q u a l t o z e r o .
T S 1 2 a n d T S 1 3 :
A t e m p o r a r y c a l c u l a t i o n f o r r a t e o f i n t a k e o f f l u i d b y t h e b o d y ( T V Z ) i s e q u a l t o t h e
d r i n k i n g d r i v e ( A H T H ) c a u s e d b y t h e p r o d u c t o f t h e s a l t a p p e t i t e d r i v e ( S T H ) a n d t h e
a n t i d i u r e t i c - t h i r s t d r i v e ( A H T H ) , p l u s t h e a n g i o t e n s i n - t h i r s t d r i v e ( A N M T H ) . B l o c k
T S 1 3 s e t s t h e l o w e r l i m i t o f ( T V Z ) t o z e r o .
T S 1 4 , T S 1 5 , a n d T S 1 6 :
T h i s i s a d e l a y c i r c u i t w h i c h c a u s e s t h e a c t u a l r a t e o f f l u i d i n t a k e ( T V D ) t o b e d e l a y e d
w i t h r e s p e c t t o c h a n g e s i n t h e t e m p o r a r i l y c a l c u l a t e d r a t e o f f l u i d i n t a k e ( T V Z ) b y a
t i m e c o n s t a n t T V D L L . A l s o s h o w n i n B l o c k T S 1 4 i s a v a r i a b l e ( D R ) t h a t c a n b e u s e d f o r
f o r c e d i n p u t o f w a t e r o v e r a n d a b o v e t h e n a t u r a l d r i n k i n g d e s i r e s ; t h i s c a n b e u s e d f o r
i n t r a v e n o u s i n f u s i o n o f w a t e r a s w e l l .
TS8:
Calculation of a thirst drive (AHTH) based on antidiuretic hormone and salt
appetite by multiplying three factors, the salt appetite drive (STH), the antidiuretic
hormone concentration multiplier (AHCM), and a constant.
Encapsulation grouping component containing all the components in the Thirst, Drinking and Salt Appetite Model.
The inputs and outputs of the Thirst, Drinking and Salt Appetite Model must be passed by this component.
TS13:
Block TS13 sets the lower limit of (TVZ) to zero.