Table 1.

Intrinsic properties of DLM neurons

Parameter measuredType I (n = 41)Type II (n = 8)
Resting membrane potential (mV)−55.1  ± 4.7−56.9  ± 2.9
Input resistance (MΩ)1-a419  ± 1871212  ± 391
Membrane time constant (msec)1-b23.2  ± 11.644.6  ± 10.8
Spike duration at half amplitude (msec)1-a0.73  ± 0.221.70  ± 0.50
Current to elicit first action potential (pA)1-a91  ± 6120  ± 7
Amplitude of fast AHP (mV)1-c18.5  ± 6.715.8  ± 4.2
Time to reach the peak of fast AHP (msec)b,d1.55  ± 0.918.6  ± 7.4
  • Values given represent mean ± SD. AHP, after hyperpolarization.

  • F1-a Significant difference with p< 0.05.

  • F1-b Significant difference with p< 0.01.

  • F1-c AHP amplitude was measured from the spike take-off point to the peak of the AHP.

  • F1-d Time to peak of the fast AHP was measured from the time when, during the falling phase of the action potential, the membrane potential crossed the spike take-off point.