Previous page 3.2.3.2.2.2.2.1. Voltage-dependent sodium channel   328 / 795  Next page 3.2.3.2.2.2.2.2. Calcium channel Return 3.2.3.2.2.2.2.1. Voltage-dependent sodium channel
Notes
      3. Old stuff
          3.2. Old physio stuff (around 2005)
              3.2.3. Physiology
                  3.2.3.2. Cardiovascular
                      3.2.3.2.2. Heart
                          3.2.3.2.2.2. Electrical activity
                              3.2.3.2.2.2.2. Fast-response cardiac action potential
                                  3.2.3.2.2.2.2.1. Voltage-dependent sodium channel
 3.2.3.2.2.2.2.1.1. Refractory period 

Refractory period

Absolute refractory period

aka Effective refractory period

While h gates are completely closed

  • No response to stimulation
  • Prevents tetanic contraction
  • ARP last till during phase 3 where Vm reaches about -50mV [BL8:p26]

 

Relative refractory period

During the period between the end of ERP and full repolarisation (phase 4), action potential can be produced, but:

  • Stronger stimulus is needed
  • Amplitude of the AP produced reduced
  • Conduction velocity reduced
  • Duration of the AP reduced (??due to incomplete inactivation of ik current)
Custom fields
3 :20050815
Previous page 3.2.3.2.2.2.2.1. Voltage-dependent sodium channel Next page 3.2.3.2.2.2.2.2. Calcium channel Return 3.2.3.2.2.2.2.1. Voltage-dependent sodium channel
Table of contents  | Bibliography  | Index
Revised at