PMID- 8201409
OWN - NLM
STAT- MEDLINE
DCOM- 19940706
LR  - 20220309
IS  - 0022-3077 (Print)
IS  - 0022-3077 (Linking)
VI  - 71
IP  - 3
DP  - 1994 Mar
TI  - Differential effects of muscimol microinjection into dorsal and ventral aspects 
      of the premotor cortex of monkeys.
PG  - 1151-64
AB  - 1. A gamma aminobutyric acid (GABAA) receptor agonist, muscimol (Sigma, 5 
      micrograms/microliters solution), and a GABAB receptor agonist and antagonist, 
      baclofen and phaclofen, respectively, were injected (1.0 microliter) into the 
      dorsal and ventral aspects of the premotor cortex (PM) of two Japanese monkeys 
      (Macaca fuscata), while they were performing a motor task that required wrist 
      flexion or extension to a target. The correct movement was instructed by either 
      1) a conditional color cue [green or red light emitting diodes (LED)] equidistant 
      from the targets or 2) a directional cue toward extension or flexion (right or 
      left LED). When the green or right LED was illuminated, extension was to be 
      performed. When the red or left LED was illuminated, flexion was required. The 
      movement was triggered by a visual stimulus either simultaneously with the 
      instruction stimulus or after a variable delay. 2. Before drug injection, 
      single-unit recordings were made to select injection sites 1) in the dorsal 
      aspect of the PM (PMd) around the superior precentral sulcus where typical 
      set-related activity was frequently recorded and 2) in the ventral aspect of the 
      PM (PMv) immediately caudal to the genu of the arcuate sulcus where 
      movement-related neurons were densely located. 3. Behavioral deficits were 
      observed primarily at the time muscimol, but not baclofen or phaclofen, was 
      injected. Furthermore, muscimol effects were short-lasting: deficits were most 
      frequently observed during the 10-min injection period but seldom after 
      completion of injection. 4. When muscimol was injected into the PMd, there was an 
      increase in the number of direction errors primarily when the conditional cues 
      were presented. The initiated movements were similar in amplitude and velocity to 
      the preinjection behavior. In contrast, when muscimol was injected into the PMv, 
      many of the initiated movements showed smaller amplitudes and slower velocities, 
      but few direction errors were made. 5. These results suggest that the PMd and PMv 
      play differential roles in motor control: the PMd is more important than PMv in 
      conditional motor behavior and plays a role in the preparation for forthcoming 
      movements. In contrast, the PMv is more specialized for a role in the execution 
      of visually guided movements.
FAU - Kurata, K
AU  - Kurata K
AD  - Department of Physiology, Tohoku University School of Medicine, Sendai, Japan.
FAU - Hoffman, D S
AU  - Hoffman DS
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
PL  - United States
TA  - J Neurophysiol
JT  - Journal of neurophysiology
JID - 0375404
RN  - 0 (Receptors, GABA-A)
RN  - 108351-35-5 (phaclofen)
RN  - 2763-96-4 (Muscimol)
RN  - H789N3FKE8 (Baclofen)
SB  - IM
MH  - Animals
MH  - Appetitive Behavior/drug effects
MH  - Attention/drug effects
MH  - Baclofen/analogs & derivatives/pharmacology
MH  - Brain Mapping
MH  - Macaca
MH  - Male
MH  - Membrane Potentials/drug effects
MH  - Microinjections
MH  - Motor Cortex/*drug effects
MH  - Motor Skills/*drug effects
MH  - Muscimol/*pharmacology
MH  - Neurons/drug effects
MH  - Orientation/drug effects
MH  - Psychomotor Performance/*drug effects
MH  - Receptors, GABA-A/drug effects
EDAT- 1994/03/01 00:00
MHDA- 1994/03/01 00:01
CRDT- 1994/03/01 00:00
PHST- 1994/03/01 00:00 [pubmed]
PHST- 1994/03/01 00:01 [medline]
PHST- 1994/03/01 00:00 [entrez]
AID - 10.1152/jn.1994.71.3.1151 [doi]
PST - ppublish
SO  - J Neurophysiol. 1994 Mar;71(3):1151-64. doi: 10.1152/jn.1994.71.3.1151.