Abstract:

Objective To investigate changes of electrophysiological characteristics of cortical GABAergic neurons during mouse development. Methods Mice aged 6-12 d (eye-unopen group) and 15-22 d (eye-open group) were sacrificed. Cortical slices were quickly produced and immersed in oxygenated artificial cerebrospinal fluid at 25 ℃ for 1 h. The electrophysiological characteristics of GABAergic neurons were recorded by Axoclamp-2B amplifier, including absolute refractory period (ARP), inter-spike interval (ISI), standard deviation of spike timing (SDST) of action potential. The effects of changing depolarizing stimulus intensity on electrophysiological characteristics of cortical GABAergic neurons of developing mice were analyzed with Clampfit 10 software. Results ARP, ISI, and SDST in eye-open group reduced as compared with the eye-unopen group. ARP, ISI, and SDST of mouse cortical GABAergic neurons reduced with the increase in stimulus intensity. Conclusion Reduced ARP of mouse cortical GABAergic neurons during development results in improved regulation of timing and accuracy for firing action potential. The increase in stimulus intensity facilitates the functional development of GABAergic neurons.

Key words: development, GABAergic neuron, depolarizing stimulus, neural coding