Mesoscopic model of spontaneous synaptic size fluctuations (Hazan & Ziv 2020)

 Download zip file 
Help downloading and running models
Sizes of glutamatergic synapses vary tremendously, even when formed on the same neuron. This diversity is commonly thought to reflect the outcome of activity-dependent forms of synaptic plasticity, yet activity-independent processes might also play some part. Here we show that in neurons with no history of activity whatsoever, synaptic sizes are no less diverse. We show that this diversity is the product of activity-independent size fluctuations, which are sufficient to generate a full repertoire of synaptic sizes at correct proportions. By combining modeling and experimentation we expose reciprocal relationships between size fluctuations, synaptic sizes and synaptic counts, and show how these phenomena might be connected through the dynamics of synaptic molecules as they move in, out and between synapses.
1 . Hazan L, Ziv NE (2020) Activity dependent and independent determinants of synaptic size diversity. J Neurosci [PubMed]
Model Information (Click on a link to find other models with that property)
Model Type: Synapse;
Brain Region(s)/Organism:
Cell Type(s):
Gap Junctions:
Simulation Environment: C or C++ program;
Model Concept(s): Stochastic simulation; Synaptic noise; Reaction-diffusion;
Implementer(s): Ziv, Noam [noamz at];
Standard definitions and types, Bob Jenkins
#ifndef STANDARD
# define STANDARD
# ifndef STDIO
#  include <stdio.h>
#  define STDIO
# endif
# ifndef STDDEF
#  include <stddef.h>
#  define STDDEF
# endif
typedef  unsigned long long  ub8;
#define UB8MAXVAL 0xffffffffffffffffLL
#define UB8BITS 64
typedef    signed long long  sb8;
#define SB8MAXVAL 0x7fffffffffffffffLL
typedef  unsigned long  int  ub4;   /* unsigned 4-byte quantities */
#define UB4MAXVAL 0xffffffff
typedef    signed long  int  sb4;
#define UB4BITS 32
#define SB4MAXVAL 0x7fffffff
typedef  unsigned short int  ub2;
#define UB2MAXVAL 0xffff
#define UB2BITS 16
typedef    signed short int  sb2;
#define SB2MAXVAL 0x7fff
typedef  unsigned       char ub1;
#define UB1MAXVAL 0xff
#define UB1BITS 8
typedef    signed       char sb1;   /* signed 1-byte quantities */
#define SB1MAXVAL 0x7f
typedef                 int  word;  /* fastest type available */

#define bis(target,mask)  ((target) |=  (mask))
#define bic(target,mask)  ((target) &= ~(mask))
#define bit(target,mask)  ((target) &   (mask))
#ifndef min
# define min(a,b) (((a)<(b)) ? (a) : (b))
#endif /* min */
#ifndef max
# define max(a,b) (((a)<(b)) ? (b) : (a))
#endif /* max */
#ifndef align
# define align(a) (((ub4)a+(sizeof(void *)-1))&(~(sizeof(void *)-1)))
#endif /* align */
#ifndef abs
# define abs(a)   (((a)>0) ? (a) : -(a))
#define TRUE  1
#define FALSE 0
#define SUCCESS 0  /* 1 on VAX */

#endif /* STANDARD */

Loading data, please wait...