The interlaminar glia: from serendipity to hypothesis.

Area of Science:

• Neuroscience
• Cell Biology
• Primate Anatomy

Background:

• Research at UNA laboratories since 1992 focused on glial processes in the cerebral cortex.
• Classical astroglial cells are typically intralaminar (within layers).

Observation:

• Serendipitous observation of unusually long glial processes in superficial cortical layers of hemiparkinsonian Cebus apella monkeys.
• These processes were termed 'interlaminar' to distinguish them from intralaminar glial cells.

Findings:

• Expanded sampling across mammalian orders and species revealed interlaminar glial processes as a primate characteristic.
• These processes are affected by neuropathological conditions (e.g., Down syndrome [DS], Alzheimer disease [AD]) and experimental sensory input alterations.
• Evidence suggests thalamic involvement in the normal expression of interlaminar glial processes.

Implications:

• Speculative roles for interlaminar glial processes in cerebral cortex organization are proposed.
• Understanding their ontogenetic development, phylogenetic evolution, and aging changes is crucial.
• Further research into their function in both health and disease is warranted.