Increase in Single L-Type Calcium Channels in Hippocampal Neurons During Aging

TLDR

Voltage‑activated calcium influx is increased in CA1 hippocampal neurons during aging, yet the molecular basis remains unknown. The partially dissociated hippocampal “zipper” slice preparation was employed to record single Ca²⁺ channel activity in CA1 neurons from adult and aged rats. Aged rats exhibited higher total L‑type Ca²⁺ channel activity due to increased density of functional channels, and this rise inversely correlated with learning performance, implicating a potential role in age‑related neurodegeneration.

Abstract

Voltage-activated calcium (Ca 2+ ) influx is increased in mammalian CA1 hippocampal neurons during aging. However, the molecular basis for this elevation is not known. The partially dissociated hippocampal (“zipper'') slice preparation was used to analyze single Ca 2+ channel activity in CA1 neurons of adult and aged rats. Total L-type Ca 2+ channel activity in patches was found to increase with aging, primarily because of an increase in the density of functional channels. Learning in aged animals was inversely correlated with channel density. This increase in functional Ca 2+ channels with aging could underlie the vulnerability of neurons to age-associated neurodegenerative conditions.