Ion Channel Development, Spontaneous Activity, and Activity-Dependent Development in Nerve and Muscle Cells

Abstract

At specific stages of development, nerve and muscle cells generate spontaneous electrical activity that is required for normal maturation of intrinsic excitability and synaptic connectivity. The patterns of this spontaneous activity are not simply immature versions of the mature activity, but rather are highly specialized to initiate and control many aspects of neuronal development. The configuration of voltage- and ligand-gated ion channels that are expressed early in development regulate the timing and waveform of this activity. They also regulate Ca2+ influx during spontaneous activity, which is the first step in triggering activity-dependent developmental programs. For these reasons, the properties of voltage- and ligand-gated ion channels expressed by developing neurons and muscle cells often differ markedly from those of adult cells. When viewed from this perspective, the reasons for complex patterns of ion channel emergence and regression during development become much clearer.

Bioengineered functional brain-like cortical tissue

“…These features supported the viability of millimeter-sized tissues that was well beyond the diffusion limitations for gels (23). It is presently unclear whether the eventual decrease of the tissue viability may be caused by a lack of sustained neuronal activity (39). The long-term viability of this brain tissue system could be further extended by incorporating external biochemical and/or electrical stimulation to simulate the signaling environment in the brain and perfusion systems to improve diffusion.…”

ERG Conductance Expression Modulates the Excitability of Ventral Horn GABAergic Interneurons That Control Rhythmic Oscillations in the Developing Mouse Spinal Cord

“…In the embryonic spinal cord, glycine progressively becomes the dominant force in driving more mature patterns of activity, such as coordinated locomotor-like bursts (Bonnot et al, 1998;Whelan et al, 2000). GABAergic interneurons appear to control the occurrence of spontaneous activity that, although not locomotor in nature, is seemingly necessary for normal motor network development (Barbeau et al, 1999;Gao et al, 2001;Moody and Bosma, 2005).…”

Self‐organization in the developing nervous system: Theoretical models

“…Spontaneous neural activity in development is not restricted to the visual system; it is found in many other systems, including hippocampus and spinal cord (O'Donovan, 1999), as well as in cultures of cortical neurons (Maeda et al, 1995). Furthermore, rather than being implicated only in the development of neural connections, its role in development is quite varied, influencing many different aspects of neural development via the regulation of intracellular calcium (see Moody and Bosma, 2005, for review). For example, diverse developmental events in cortex such as neuronal migration, neuronal survival, and dendritic arborization are all thought to rely on calcium influx, mediated by spontaneous neuronal activity (Moody and Bosma, 2005).…”