AUTORADIOGRAPHIC ESTIMATION OF THE EXTENT OF REVERSIBLE INACTIVATION PRODUCED BY MICROINJECTION OF LIDOCAINE AND MUSCIMOL IN THE RAT

NEUROSCIENCE LETTERS

卷:127

Article

关键词: AUTORADIOGRAPHY;    CEREBRAL GLUCOSE UTILIZATION;    GABA;    LIDOCAINE;    MUSCIMOL;    REVERSIBLE INACTIVATION;   

DOI  :  10.1016/0304-3940(91)90784-Q

来源: Elsevier

【 摘 要 】

We used autoradiography to examine the extent of reversible inactivation produced by microinjection of lidocaine (40-mu-g/mu-l saline) and muscimol (1-mu-g/mu-l saline). We measured intracortical spread of tracer amounts of labelled drug and local changes in uptake of [1-C-14]glucose produced by the microinjection. The maximal average radii of regions of drug spread were 1.7 mm for both [C-14]lidocaine and [H-3]muscimol and were achieved within the first 20 min postinjection. The width of lidocaine injections decreased at longer postinjection times (30-60 min) but the width of muscimol injections remained relatively constant (30-120 min). Lidocaine radioactivity decreased faster from the injection site than muscimol radioactivity. Glucose autoradiograms showed a discrete region of maximally reduced glucose uptake (1.4 mm for lidocaine and 1.0 mm for muscimol) surrounded by a region of less reduced glucose uptake (up to approximately 3 mm). These findings suggest that, in the cortex, the effects of focal inactivation extend beyond the region of drug spread. Diffuse effects may be mediated of disfacilitation of cortico-cortical circuits.

【 授权许可】

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