Patterns of glucose use after bicuculline-induced convulsions in relationship to gamma-aminobutyric acid and mu-opioid receptors in the ventral pallidum--functional markers for the ventral pallidum.
Bicuculline-induced convulsions increased glucose use throughout the brain and sharply demarcated the ventral pallidum and globus pallidus. Glucose use in the nucleus accumbens also increased after bicuculline-induced convulsions, except for a circumscribed region in the dorsomedial shell. Since the projection from the nucleus accumbens to the ventral pallidum contains gamma-aminobutyric acid (GABA) and the opioid peptide, enkephalin, the pattern of increased glucose use in the ventral pallidum and nucleus accumbens after bicuculline-induced convulsions was compared to the topography of GABAA and mu-opioid receptors. The pattern of glucose use in the nucleus accumbens and ventral pallidum resembled the topography of GABAA, but differed from that of mu-opioid receptors. Bicuculline may disinhibit GABAergic efferents to the ventral pallidum resulting in a dramatic increase in glucose use within striatopallidal synaptic terminals as well as in local terminals of the pallidal projection neurons.
Churchill
L
L
Department of Veterinary and Comparative Anatomy, Pharmacology and Physiology, Washington State University, Pullman 99164-6520.
Cross
R S
RS
Pazdernik
T L
TL
Nelson
S R
SR
Zahm
D S
DS
Heimer
L
L
Kalivas
P W
PW
D000818:Animals; D001345:Autoradiography; D001640:Bicuculline; D015415:Biomarkers / Q000737:chemistry; D005917:Globus Pallidus / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011963:Receptors, GABA-A / Q000032:analysis*; D011957:Receptors, Opioid / Q000032:analysis*; D017450:Receptors, Opioid, mu; D012640:Seizures / Q000139:chemically induced / Q000378:metabolism*; D013373:Substance P / Q000032:analysis
D015415:Biomarkers; D011963:Receptors, GABA-A; D011957:Receptors, Opioid; D017450:Receptors, Opioid, mu; D013373:Substance P; D005947:Glucose; D001640:Bicuculline