A study comparing the actions of gabapentin and pregabalin on the electrophysiological properties of cultured DRG neurones from neonatal rats

Table 2 Actions of pregabalin (25 μM) on K⁺-evoked Ca²⁺influx in the continual presence or absence of 100 μM GABA.

GABA sensitivity	Mean percentage of control Ca²⁺ influx	Number of neurones	Proportion of Neurones
Responders	110 ± 2 %	3 of 18	17 %
Responders	77 ± 2 %	15 of 18	83 %
Non-responders	121 ± 4 %	10 of 23	43 %
Non-responders	81 ± 3 %	13 of 23	57 %
Control	169 ± 24 %	28 of 49	57 %
Control	85 ± 2 %	21 of 49	43 %

Responders were those neurones in which GABA evoked a transient rise in intracellular Ca²⁺. Non-responder showed no change in fura-2 fluorescence ratio in response to GABA. Controls where neurones that pregabalin was applied to without GABA being present. The amplitudes of the GABA responses did not vary with the inhibitory or enhancing responses to pregabalin.