To elucidate physiological and pathophysiological mechanisms in pain pathways we are using state of the art electrophysiological in vivo and in vitro recordings of cellular and network activity in the spinal dorsal horn a key area for central processing of nociceptive information.
We record C-fiber-evoked field potentials in superficial spinal laminae of rats and mice in response to electrical and natural stimulation of the sciatic nerve to investigate the anti- and pronociceptive properties of opioids by measuring their acute and long-lasting effects on synaptic transmission in vivo [1,2,5].
Conventional and perforated whole-cell patch-clamp recordings combined with infrared differential interference contrast (IR-DIC) video microscopy are routinely used in our lab to measure excitatory and inhibitory synaptic currents in identified neurons in spinal cord slice preparations from rats and transgenic mice [3,4], e.g. to study the effect of GABAergic inhibition on nociceptive processing in superficial dorsal horn. The long dorsal roots attached allows us to selectively stimulate primary sensory afferents thereby taking advantage of the outstanding feature of the nociceptive spinal system, that input and output pathways are well-defined. To investigate spinal synaptic plasticity we combine patch-clamp recordings with live-cell imaging approaches such as Ca2+ imaging [1].