Table 1.

Electrophysiological investigations in Cx32-deficient mice

GenotypeCx32-deficientwild typeCx32-deficientWild type
n67710
Age4–6 months4–6 months1 year1 year
Facial nerve
  M-latency (msec)1.0  ± 0.11.1  ± 0.11.0  ± 0.11.1  ± 0.2
  M-amplitude (mV)15  ± 212  ± 411  ± 2*14  ± 3
Sciatic nerve
 Proximal stimulation
  M-latency (msec)1.7  ± 0.2ns1.5  ± 0.21.5  ± 0.21.6  ± 0.2
  M-amplitude (mV)8  ± 3*12  ± 310  ± 611  ± 4
  M-duration (msec)2.2  ± 0.2ns1.8  ± 0.52.0  ± 0.5ns2.2  ± 0.5
  F-latency (msec)4.2  ± 0.24.1  ± 0.24.4  ± 0.44.4  ± 0.5
 Distal stimulation
  M-latency (msec)1.0  ± 0.1*0.8  ± 0.10.8  ± 0.11.0  ± 0.2
  M-amplitude (mV)11  ± 4ns15  ± 512  ± 312  ± 4
  M-duration (msec)2.1  ± 0.21.5  ± 0.31.9  ± 0.6ns2.2  ± 0.5
  F-latency (msec)4.8  ± 0.54.8  ± 0.25.1  ± 0.4ns4.8  ± 0.5
Motor nerve conduction velocity (m/sec)32  ± 935  ± 935  ± 10ns40  ± 12
Mixed afferent nerve conduction velocity (m/sec)42  ± 645  ± 349  ± 849  ± 9
  • M-latency, M-amplitude, and M-duration are components of the muscle response, the earliest response to nerve stimulation that travels orthogradely to elicit a compound muscle action potential. F-responses are late muscle responses. After the stimulation the stimulus first is transmitted retrogradely, eliciting a secondary response in motor neurons that is transmitted orthogradely to the muscle, thus arriving later than the M-response.

  • * p < 0.05, one-sided U test; ns, not significant.