Demir et al's 1999 mathematical model of a rabbit sinoatrial node cell
Sinoatrial Node Cell
Rabbit
Demir
S
Semahat
This model has been validated by Penny Noble of Oxford University.
2002-07-18
The University of Auckland, Bioengineering Institute
c.lloyd@auckland.ac.nz
2003-04-05
signal transduction
sinoatrial node
electrophysiology
cardiac
10362707
i_f is modulated via a direct effect of cAMP on the
voltage-dependence of its steady-state activation variable y.
Autumn
A
Cuellar
added cmeta:id's for some variables to allow referencing by PCEnv session
James Lawson
This model has been validated by Penny Noble of Oxford University and is known to run in COR and PCEnv. A PCEnv session file is also associated with this version. Model curated by Penny Noble using Demir 1994 Oxsoft Heart model code and Demir 1999 paper.
keyword
2005-04-25
Catherine
May
Lloyd
Richard
Lawson
James
2007-06-19T15:32:11+12:00
H2244
276
Parasympathetic modulation of sinoatrial node pacemaker activity in rabbit heart: a unifying model
H2221
Catherine
Lloyd
May
Lloyd
May
Catherine
Added more metadata.
Villiger
Peter
J
ACh has a direct stimulatory affect on the ACh-sensitive potassium
channel. The G-protein-mediated, direct affect of ACh on i_K_ACh
occurs via the extrajunctional M2/K_ACh muscarinic receptor. This
channel has a single gating variable a.
The T-type calcium channel has two gates, an activation gate d_T and an inactivation gate f_T.
Below is a CellML description of Demir et al's 1999 mathematical model of parasympathetic modulation of sinoatrial node (SAN) pacemaker activity in a rabbit heart. Based on experimental data, this model is a development of their earlier model of the single rabbit SAN cell (1994). Modifications have been made enabling it to mimic the important effects of the second-messenger cAMP and to simulate the response of SAN cells to the neurotransmitter acetylcholine (ACh) and isoprenaline (Iso).
The effects of Iso on i_NaK may be species dependent as it has been observed that Iso directly stimulates Na+-K+-ATPase activity in rabbit ventricular myocytes (Desilets and Baumgarten, 1986), but indirectly stimulates i_NaK in guinea pig ventricular myocytes via a PKA phosphorylation step (Gao et al. 1992, 1994). In the absence of any quantitative evidence, in this model Demir et al. have assumed that cAMP directly stimulates i_NaK in the rabbit SAN cell and that this cAMP dependency may be modelled by the equations below.
Corrected some units.
2002-07-18
100000
2
0.1
Corrected several equations.
Catherine
May
Lloyd
Changed sign of i_rel in dCai-dt equation. Changed the name of sodium-calcium pump to an exchanger. Changed U_calculation from an equals sign to an equivalent sign.
Changed the model name so the model loads in the database easier.
Catherine Lloyd
John
Clark
W
Penny
J
Noble
May
Catherine
Lloyd
2002-02-28
The Bioengineering Institute
The University of Auckland
The effects of ACh and Iso on i_Ca_L and i_K are produced indirectly via the cAMP-dependent modulation of L-type Ca2+ and K+ channel
conductance (g_Ca_L and g_K) respectively.
2002-02-25
Giles
R
Wayne
2007-12-19T13:48:43+13:00
Changed equivalent to eq in apply id line.
American Journal of Physiology
2002-02-06T00:00:00+00:00
1999-06-01