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Sensory stimuli evoke responses in cerebellar Purkinje cells (PCs) via mossy fiber-granule cell pathway.However, the properties and characterization of synaptic responses evoked by the tactile stimulus in cerebella PCs are unknown.In the present study, we investigated the synaptic responses of cerebellar PCs in response to the air-puff stimulus on the ipsilateral whisker pad in urethane-anesthetized mice.A total of 33 PCs from 35 adult (6-8 weeks old) ICR mice were studied by somatic or dendritic patch-clamp recording with biolytic staining and pharmacological methods.Under current-clamp conditions (I =0), air-puff stimulus evoked strong inhibito ry postsynaptic potentials (IPSPs) in PCs somata.Application of SR95531, a specific GABAA receptor antagonist, blocked IPSPs, and revealed the stimulus-evoked simple spike firing.Under voltage-clamp conditions, tactile stimulus evoked a sequence of transient inward currents followed by strong inhibitory postsynaptic currents (IPSCs) in both PCs stomata and dendrites.Application of GABAA receptor antagonist, SR95531 blocked IPSCs, revealed the excitatory postsynaptic currents (EPSCs) in somata and a temporal summation of parallel-fiber EPSCs in dendrites of PCs.We also demonstrated that PCs respond to both onset and offset of air-puff stimulus.These findings indicated that the tactile stimulus could not evoke the strong EPSCs and fire PCs, but induced the rapid activation of strong GABAA rereptor-mediated IPSCs in both stomata and dendrites of PCs.We propose that the inhibition play a crucial role in controlling the output of sensory information in PCs in cerebellar cortex Crus Ⅱ in mice.