PMID- 31166815
OWN - NLM
STAT- MEDLINE
DCOM- 20200429
LR  - 20200429
IS  - 1522-1598 (Electronic)
IS  - 0022-3077 (Linking)
VI  - 122
IP  - 1
DP  - 2019 Jul 1
TI  - Repetitive doublet firing in human motoneurons: evidence for interaction between 
      common synaptic drive and plateau potential in natural motor control.
PG  - 424-434
LID - 10.1152/jn.00874.2018 [doi]
AB  - The firing behavior of spinal motoneurons (MNs) is a result of processing 
      synaptic inputs by MN membrane properties, including plateau potentials, 
      fundamentally explored in animals. However, there is much less data about a 
      plateau potential role in human motor control. We explored human MN repetitive 
      doublet firing during gentle isometric voluntary muscle contractions with the aim 
      of revealing possible evidence for interaction between plateau potentials and 
      common synaptic drive known as an important determinant of MN pool firing 
      behavior. Single-motor unit (MU) repetitive firing of trapezius and triceps 
      brachii was analyzed. Subjects were asked to recruit MUs capable of firing 
      repetitive doublets. The analysis of interspike intervals (ISIs) of background 
      firing of simultaneously recorded MUs showed that beyond doublet series ISIs 
      varied, often in unison with significant correlation coefficients, demonstrating 
      common synaptic drive. During doublet series, MUs showed persistent doublet ISIs 
      (typically 4-7 ms) and a tendency to increase the number of doublets in series 
      throughout the experiment. This was consistent with involvement of MN plateau 
      potentials resulting in persistent delayed depolarization (underlying each 
      doublet) and warm-up effect. Common synaptic drive "started" doublet series; 
      probably both mechanisms controlled postdoublet ISIs. However, convincing effects 
      of plateau potentials on MU firing behavior during single firing were not found. 
      Thus our results suggest a plateau potential role in specifying the essential 
      firing pattern, doubling, of some MUs rather than its effect on firing behavior 
      of the MN pool, on the whole, during voluntary muscle contractions in humans. NEW 
      & NOTEWORTHY Properties of human motoneuron repetitive doublet firing were 
      explored during voluntary muscle contractions. It was shown for the first time 
      that these properties seem to be consistent with properties of both plateau 
      potentials, resulting in persistent delayed depolarization (underlying each 
      doublet) and common synaptic drive, starting this unusual firing; both mechanisms 
      could probably control postdoublet intervals. A convincing effect of plateau 
      potentials on motoneuron single-spike firing, despite doublet firing, was not 
      found.
FAU - Kudina, Lydia P
AU  - Kudina LP
AD  - Institute for Information Transmission Problems (Kharkevich Institute), Russian 
      Academy of Sciences , Moscow , Russia.
FAU - Andreeva, Regina E
AU  - Andreeva RE
AD  - Institute for Information Transmission Problems (Kharkevich Institute), Russian 
      Academy of Sciences , Moscow , Russia.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20190605
PL  - United States
TA  - J Neurophysiol
JT  - Journal of neurophysiology
JID - 0375404
SB  - IM
MH  - *Action Potentials
MH  - Adult
MH  - Humans
MH  - Isometric Contraction
MH  - Middle Aged
MH  - Motor Neurons/*physiology
MH  - Muscle, Skeletal/innervation/*physiology
MH  - Synaptic Potentials
OTO - NOTNLM
OT  - common synaptic drive
OT  - human motoneuron firing behavior
OT  - motor control
OT  - plateau potentials
OT  - repetitive doubling
EDAT- 2019/06/06 06:00
MHDA- 2020/04/30 06:00
CRDT- 2019/06/06 06:00
PHST- 2019/06/06 06:00 [pubmed]
PHST- 2020/04/30 06:00 [medline]
PHST- 2019/06/06 06:00 [entrez]
AID - 10.1152/jn.00874.2018 [doi]
PST - ppublish
SO  - J Neurophysiol. 2019 Jul 1;122(1):424-434. doi: 10.1152/jn.00874.2018. Epub 2019 
      Jun 5.