Insulindemo_Change of numerical values in some parameters are not reflected in the simulation

Hello,

I am currently and actively working with the insulindemo included in the toolbox simBiology.

for the object named Type 2 diabetic, I ran a first simulation using the default values.

Then I wanted to change the values of the parameters m5 and m6, the modification of these two values shold be reflected in the value of the initial assignment

[Basal Ins Secr] = (m6-[Basal Hepatic Extraction])/m5

using the defautl values m6 = 0.8118 and m5 = 0.0526 I get a value for the [Basal Ins Secr] of 4.0266

However, if I use m6 = 0.6471 and m5 = 0.0304 ([Basal Ins Secr] = 1.5493) and I run the simulation the value of [Basal Ins Secr] remains the same as for the defaul values.

My question is whether the values of the parameters are changeable or not.

Thank yo very much in advance, I'm looking forward to hear from you.

I wish you a very good day.

Juliana GONZALEZ

Answer 1

[Arthur Goldsipe]

Hi Juliana,

Yes, you can change these parameters. However, the values on the parameters themselves are replaced by any values specified in variants, and the Type 2 diabetic variant includes values for these two parameters. So you will either need to modify the values on the Type 2 diabetic variant, or include a second variant in the simulation that specifies the desired values for these two parameters. If you choose to specify multiple variants, you need to make sure that the one with the desired values for m5 and m6 comes last in the list, since they are applied in order.

Here's how you could use two variants at the command line:

sbioloadproject insulindemo.sbproj m1
diabeticVariant = getvariant(m1, 'Type 2 diabetic');
sim1 = sbiosimulate(m1, diabeticVariant);

Warning: Reported from Dimensional Analysis:
Cannot perform dimensional analysis for rule 'kempt definition' because of the function 'tanh' in the rule. Because UnitConversion is on, correct simulation results will depend on this expression being dimensionally correct. Additionally, SimBiology simulates the model in a unit system determined at runtime. The units are determined by the units used in the model and the model's configset. Unless the inputs and outputs to the function are dimensionless, results may change due to configset option changes, changes to the model, or version changes in SimBiology. It is recommended that input and output arguments to functions be dimensionless to ensure correct results.

sim1a = selectbyname(sim1, 'Basal Ins Secr');
% Value of [Basal Ins Secr] when using 'Type 2 diabetic' variant:
sim1a.Data(1)

ans = 4.0266

m5m6Variant = sbiovariant('m5 and m6');
addcontent(m5m6Variant, {'parameter', 'm5', 'Value', 0.0304});
addcontent(m5m6Variant, {'parameter', 'm6', 'Value', 0.6471});
sim2 = sbiosimulate(m1, [diabeticVariant, m5m6Variant]);
sim2a = selectbyname(sim2, 'Basal Ins Secr');
% Value of [Basal Ins Secr] when using both variants:
sim2a.Data(1)

ans = 1.5493

[Carmen Juliana Gonzalez]

Dear Arthur,

Thank you very much for the help.

Kind Regards,

Juliana