Computer model of clonazepam`s effect in thalamic slice (Lytton 1997)

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Accession:12631
Demonstration of the effect of a minor pharmacological synaptic change at the network level. Clonazepam, a benzodiazepine, enhances inhibition but is paradoxically useful for certain types of seizures. This simulation shows how inhibition of inhibitory cells (the RE cells) produces this counter-intuitive effect.
Reference:
1 . Lytton WW (1997) Computer model of clonazepam's effect in thalamic slice. Neuroreport 8:3339-43 [PubMed]
Model Information (Click on a link to find other models with that property)
Model Type: Realistic Network;
Brain Region(s)/Organism: Thalamus;
Cell Type(s): Thalamus geniculate nucleus (lateral) principal neuron; Thalamus reticular nucleus cell;
Channel(s): I Na,t; I T low threshold; I K; I CAN;
Gap Junctions:
Receptor(s): GabaA; Gaba;
Gene(s):
Transmitter(s): Gaba;
Simulation Environment: NEURON;
Model Concept(s): Activity Patterns; Bursting; Therapeutics; Epilepsy; Calcium dynamics;
Implementer(s): Lytton, William [billl at neurosim.downstate.edu];
Search NeuronDB for information about:  Thalamus geniculate nucleus (lateral) principal neuron; Thalamus reticular nucleus cell; GabaA; Gaba; I Na,t; I T low threshold; I K; I CAN; Gaba;
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lytton97b
README
AMPA.mod
calciumpump_destexhe.mod *
GABAA.mod
GABAB1.mod
GABALOW.mod
HH_traub.mod *
IAHP_destexhe.mod
ICAN_destexhe.mod
ICAN_voltdep.mod
Ih_old.mod *
IT_wang.mod
IT2_huguenard.mod
NMDA.mod
passiv.mod *
pregen.mod *
presyn.mod *
pulse.mod
rand.mod
bg.inc *
boxes.hoc
ctl.dat
ctlnew.dat
czp.dat
czpnew.dat
declist.hoc *
decvec.hoc *
default.hoc *
disp.hoc
Fig3.gif
Fig4.gif
geom.hoc
grvec.hoc
init.hoc
labels.hoc
local.hoc
mod_func.c
mosinit.hoc
network.hoc
neurrep8
nrnoc.hoc
params.hoc
presyn.inc *
queue.inc *
run.hoc
show.hoc
simctrl.hoc *
sns.inc *
snsarr.inc
snscode.hoc
snsgr.hoc
snshead.inc *
synq.inc *
xtmp
                            
: $Id: snshead.inc,v 1.22 1998/01/07 20:22:30 billl Exp $

VERBATIM

#define PSTCAST ((SynS *)((unsigned long) lpst))
#define QUECAST ((QueU *)((unsigned long) queu))
#define PRECAST ((PreL *)((unsigned long) link))
#define QPRCAST ((QptR *)((unsigned long) qptr))

#define PREINC  50.  /* size increment for growing the presyn array */
#define POSTINC 5.   /* size increment for growing the postsyn array */

typedef struct QueU { /* postsynaptic queue */
  double time;  /* records spike time + delay */
  short index;  /* records index of associated SynS struct */
} QueU;

/* holds all the info for accessing the queu and its tail */
typedef struct QptR {
  struct QueU *qq;     /* will point to the queu */
  double *nspk; /* will point to newspk */
  double *head; /* will point to begsyn */
  double *qln;  /* points to qlen */
  double dead;  /* Cdur + Deadtime */
  double qterm;  /* the last time put on this queue */
  int cpost;  /* user code for info about postsyn cell */
} QptR;

typedef struct SynS { /* postsynaptic structure */
  /* this stuff used presynaptically */
  short index;  /* index of this item */
  double del;   /* param: individualized delay set by user */
  double spkt;  /* state: time when next spike can begin */
  struct QptR *qpt;   /* indirection to get at the queu */

  /* for allowing mult spikes to add up */
  short chainlen;
  short chainptr;

  /* user codes */
  int ucode;  /* user code for user convenience, an arbitrary index */
  /* this stuff used postsynaptically */
  double pgm;   /* percent of gmax - set by user */
  double Rcurr; /* holds current value of R (release status), internal */
  double last;  /* time last syn will end, internal */
  int *pcpre;   /* pointer to access the presyn code */
  struct SynS **back;  /* pointer to presyn pointer to this entry */
} SynS;

/* holds all the info for accessing presyn list */
typedef struct PreL {
  int cpre;   /* user code for info about presyn cell */
  struct SynS **plst;        /* will point to post for postsyn nrn*/
  double *nnpre;     /* number of pointers currently there */
  double *mxpre;     /* number permitted before realloc required */
  double link2;       /* a copy of the link information to confirm correct hook up */
} PreL;

ENDVERBATIM

Lytton WW (1997) Computer model of clonazepam's effect in thalamic slice. Neuroreport 8:3339-43[PubMed]

References and models cited by this paper

References and models that cite this paper

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   Thalamic quiescence of spike and wave seizures (Lytton et al 1997) [Model]

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