Protein changes in the rat's prefrontal and "inferotemporal" cortex after exposure to visual problems

Neural cell adhesion molecule (NCAM) as a quantitative marker in synaptic remodeling

The neural cell adhesion molecule (NCAM) participates in adhesion and neuritic outgrowth during nervous system development. In the adult brain, NCAM is considered to be involved in neuronal sprouting and synaptic remodeling. The NCAM concentration of brain tissue has proved to be a useful marker of these processes, especially when viewed in comparison with the concentration of a marker of mature synapses, e.g. D3-protein (SNAP-25) or synaptophysin. The present review focusses on studies of adult brain in which NCAM concentration estimates and NCAM/D3 ratios have been used to evaluate the rate of synaptic remodeling in brain damage and degenerative diseases.

Electroconvulsive stimulations, learning, and protein changes in the rat brain

Two groups of rats were subjected to 17 training sessions on an operant task demanding the sequential operation of two manipulanda, while two other groups were left with no training experience. Within both the trained and passive groups one was exposed to a series of 12 electroconvulsive stimulations. The series of training and stimulation sessions were concurrent but arranged in such a way that at least 24 h always separated training and stimulation. Upon completion of the behavioural part of the experiment the concentrations of the marker proteins neural cell adhesion molecule (NCAM), D3, synaptophysin, and S100 were estimated in the prefrontal and occipital parts of the cortex, the hippocampus, and in the total forebrain. The electroconvulsively stimulated animals demonstrated severe impairment of learning. The pattern of marker protein concentrations indicated that acquisition and/or performance of the task and exposure to electroconvulsive stimulation were both accompanied by similar patterns of synaptic changes: an increased concentration of small synaptic vesicles in both the prefrontal cortex and the total forebrain and an increased synaptic remodulation in the prefrontal cortex.