Short-term plasticity visualized with flavoprotein autofluorescence in the somatosensory cortex of anaesthetized rats

In the present study, short‐term plasticity of somatosensory neural responses was investigated using flavoprotein autofluorescence imaging in rats anaesthetized with urethane (1.5 g/kg, i.p.) Somatosensory neural activity was elicited by vibratory skin stimulation (50 Hz for 1 s) applied on the surface of the left plantar hindpaw. Changes in green autofluorescence (λ = 500–550 nm) in blue light (λ = 450–490 nm) were elicited in the right somatosensory cortex. The normalised maximal fluorescence responses (ΔF/F) was 2.0 ± 0.1% (n = 40). After tetanic cortical stimulation (TS), applied at a depth of 1.5–2.0 mm from the cortical surface, the responses elicited by peripheral stimulation were significantly potentiated in both peak amplitude and size of the responsive area (both P