Neurotrophins induce formation of functional excitatory and inhibitory synapses between cultured hippocampal neurons

Synaptic plasticity in cortical systems

Recent studies indicate that synapse addition and/or loss is associated with different types of learning. Other factors influencing synaptogenesis and synapse loss include neurotrophins, hormones, and the induction of long-term potentiation. An emerging view of synaptic plasticity suggests that local neurotrophin action and synaptically associated protein synthesis may promote synaptic remodelling and changes in receptor expression or activation.

Neurotrophin regulation of synaptic transmission

Examples of signaling molecules that are devoted to neuronal development at the exclusion of other functions are scarce. It may then come as no surprise to learn that a family of molecules that promote neuronal survival, differentiation and outgrowth also regulate synaptic transmission at both developing and mature synapses. Indeed, many studies over the past five years have shown that neurotrophins, including nerve growth factor (NGF), neurotrophin-3 (NT-3), NT-4/5 and brain-derived neurotrophic factor (BDNF), have both rapid and long-latency influences on synaptic strength. New research has highlighted the enormous range of neurotrophin actions at both developing and mature synapses, demonstrating that transmission can be enhanced or reduced at excitatory and inhibitory synapses by either pre- or postsynaptic mechanisms.

The neurochip: a new multielectrode device for stimulating and recording from cultured neurons

The neurochip is a silicon micromachined device upon which cultured mammalian neurons can be continuously and individually monitored and stimulated. The neurochip is based upon a 4 x 4 array of metal electrodes, each of which has a caged well structure designed to hold a single mature cell body while permitting normal outgrowth of neural processes. We demonstrate that this device is capable of maintaining cell survival, and that the electrodes can both record and stimulate electrical activity in individual cells with no crosstalk between channels.

[Diffuse primary leptomeningeal gliomatosis]

A woman died at the age of 22 years. Lifetime diagnosis had been inflammatory arachnopathy. The course of the disease had taken at least 6 years. Autopsy revealed primary diffuse leptomeningeal astrocytoma of the brain and spinal cord without neoplastic foci in the parenchyma of the central nervous system. Patchy dystrophic calcifications were recorded from the cerebral and cerebellar cortex.