Cell death of spinal interneurones.

Area of Science:

• Neuroscience
• Developmental Biology
• Cell Biology

Background:

• Neuronal death during development is established for motoneurons and dorsal root ganglion cells.
• Cell survival is typically regulated by target and input connections to match neuronal population sizes.
• Interneurones, with diffuse connections, were thought to be excluded from this regulation.

Purpose of the Study:

• To review evidence for spinal interneurone death in rats.
• To discuss factors influencing spinal interneurone death.
• To propose alternative mechanisms regulating interneurone survival.

Main Methods:

• Review of existing studies on rat spinal cord development and injury.
• Analysis of factors influencing interneurone cell death.
• Discussion of functional interneurone types and their vulnerability.

Main Results:

• Spinal interneurone death occurs naturally during development and is induced by peripheral nerve injury.
• Evidence suggests interneurone death is not primarily regulated by target connections.
• Functional interneurone types may exhibit varying vulnerability to cell death.

Conclusions:

• Developmental interneurone death in the spinal cord is likely a plastic response to altered sensory activation.
• This process differs from the size-matching mechanism seen in other neuronal populations.
• Interneurone death may have implications for neurodegenerative diseases.