[Post-denervation changes in the membrane potentials of muscle fibers in cold-adapted rats]. / Postdenervatsionnye izmeneniia membrannykh potentsialov myshechnykh volokon adaptirovannykh k kholodu krys.

In rats, the resting and active MPs of single muscle fibers of fast (m. gastrocnemius) and slow (m. soleus) denervated muscles were measured in cold-adapted and control animals. Electrophysiological characteristics of muscle fibers were studied within 10 days after dissection of the sciatic nerve. Postdenervation changes in the control group were less obvious in the fast fibers, whereas in cold-adapted rats they were lesser in the slow muscle fibers.

[Electrophysiological characteristics of muscle fibers in cold-adapted rats]. / Elektrofiziologicheskaia kharakteristika myshechnykh volokon krys, adaptirovannykh k kholodu.

In rats, the membrane APs of single muscle fibers of fast (m. gastrocnemius) and slow (m. soleus) muscles were measured in cold--adapted animals and in a control group. In cold--adapted rats the membrane AP of slow muscle fibers was higher than in the control group, whereas in the fast muscle fibers the AP was decreased. The AP in cold--adapted rats fast muscle fibers was shorter and in the slow muscle fibers longer than in muscles of the control group. The data suggest that the excitation processes are changed in both types of muscles in cold--adapted rats.

[Effect of cold adaptation on the resting membrane potential of muscle fibers]. / Vliianie adaptatsii k kholodu na membrannyi potentsial pokoia myshechnogo volokna.

In experiments on rats the membrane potential of single muscle fibers in fast (m. gastrocnemius) and slow (m. soleus) muscles were measured in animals adapted to cold and in the control group. The dynamics of the membrane potential was studied also during the first 60 min after the sciatic nerve dissection. In cold adapted rats the membrane potential of slow muscle fibers was higher than in the control group, but in the fast muscle fibers there was no difference between the two groups of animals. The denervation of muscles resulted in a progressive increase in the membrane potential. This hyperpolarization seems to be the result of deprivation of the c. n. s. from the activating influence. The data suggest that cold adaptation affects mainly the slow muscle fibers.

[Resting potential and action potential of an individual frog muscle fiber during reciprocal inhibition]. / Potentisal pokoia i potentsial deistviia odinochnogo myshechnogo volokna liagushki pri retsiproknom tormozhenii.

In single muscle fibres of the frog m. tibialis anticus longus resting membrane potential and parameters of the action potential were studied in situ during rest and during the resiprocal inhibition of its spinal center. Development of the reciprocal inhibition increased the resting membrane potential, the amplitude of the action potential, but decreased the time course and latency of the action potential. The changes in functional properties of single muscle fibres seem to occur as the result of deprovation of central influences due to the reciprocal inhibition.