PMID- 15232667
OWN - NLM
STAT- MEDLINE
DCOM- 20050302
LR  - 20181113
IS  - 0014-4819 (Print)
IS  - 0014-4819 (Linking)
VI  - 159
IP  - 2
DP  - 2004 Nov
TI  - Tonic differential supraspinal modulation of PAD and PAH of segmental and 
      ascending intraspinal collaterals of single group I muscle afferents in the cat 
      spinal cord.
PG  - 239-50
AB  - We compared in the anesthetized cat the effects of reversible spinalization by 
      cold block on primary afferent depolarization (PAD) and primary afferent 
      hyperpolarization (PAH) elicited in pairs of intraspinal collaterals of single 
      group I afferents from the gastrocnemius nerve, one of the pairs ending in the L3 
      segment, around the Clarke's column nuclei, and the other in the L6 segment 
      within the intermediate zone. PAD in each collateral was estimated by independent 
      computer-controlled measurement of the intraspinal current required to maintain a 
      constant probability of antidromic firing. The results indicate that the 
      segmental and ascending collaterals of individual afferents are subjected to a 
      tonic PAD of descending origin affecting in a differential manner the excitatory 
      and inhibitory actions of cutaneous and joint afferents on the pathways mediating 
      the PAD of group I fibers. The PAD-mediating networks appear to function as 
      distributed systems whose output will be determined by the balance of the 
      segmental and supraspinal influences received at that moment. It is suggested 
      that the descending differential modulation of PAD enables the intraspinal 
      arborizations of the muscle afferents to function as dynamic systems, in which 
      information transmitted to segmental reflex pathways and to Clarke's column 
      neurons by common sources can be decoupled by sensory and descending inputs, and 
      funneled to specific targets according to the motor tasks to be performed.
FAU - Rudomin, P
AU  - Rudomin P
AD  - Department of Physiology, Biophysics and Neurosciences del IPN, Centro de 
      Investigacion y de Estudios Avanzados, Av. Instituto Politecnico Nacional 2508, 
      DF 07300, Mexico. rudomin@fisio.cinvestav.mx
FAU - Lomeli, J
AU  - Lomeli J
FAU - Quevedo, J
AU  - Quevedo J
LA  - eng
GR  - NS 09196/NS/NINDS NIH HHS/United States
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
DEP - 20040630
PL  - Germany
TA  - Exp Brain Res
JT  - Experimental brain research
JID - 0043312
SB  - IM
MH  - Afferent Pathways/*physiology
MH  - Animals
MH  - Cats
MH  - Efferent Pathways/*physiology
MH  - Excitatory Postsynaptic Potentials/physiology
MH  - Female
MH  - Hypothermia, Induced
MH  - Male
MH  - Muscle Spindles/*physiology
MH  - Muscle, Skeletal/innervation/physiology
MH  - Neural Inhibition/*physiology
MH  - Presynaptic Terminals/physiology
MH  - Reflex, Stretch/physiology
MH  - Spinal Cord/*physiology
MH  - Spinal Nerve Roots/*physiology
MH  - Synaptic Transmission/physiology
EDAT- 2004/07/03 05:00
MHDA- 2005/03/03 09:00
CRDT- 2004/07/03 05:00
PHST- 2003/12/22 00:00 [received]
PHST- 2004/04/20 00:00 [accepted]
PHST- 2004/07/03 05:00 [pubmed]
PHST- 2005/03/03 09:00 [medline]
PHST- 2004/07/03 05:00 [entrez]
AID - 10.1007/s00221-004-1953-7 [doi]
PST - ppublish
SO  - Exp Brain Res. 2004 Nov;159(2):239-50. doi: 10.1007/s00221-004-1953-7. Epub 2004 
      Jun 30.