Effect of vinconate against alterations in [3H]naloxone, [3H]MK-801 and [3H]muscimol bindings after transient cerebral ischemia in gerbils.
We examined the alterations of opioid (naloxone), N-methyl-D-aspartate and gamma-aminobutyric acidA receptors in the gerbil brain 7 days after cerebral ischemia using [3H]naloxone, [3H]MK-801 and [3H]muscimol autoradiography, respectively. We also evaluated the effect of vinconate against the alterations in these receptors. Transient cerebral ischemia was induced for 10 minutes, and vinconate (100 and 300 mg/kg) was given intraperitoneally 10 minutes before ischemia. [3H]MK-801 binding showed a more severe reduction than [3H]naloxone binding 7 days after cerebral ischemia, whereas [3H]muscimol binding was unchanged in almost all brain regions. Vinconate showed a significant prevention against the reduction in [3H]naloxone binding in all brain areas. This drug also prevented a significant reduction in [3H]MK-801 binding in most of the brain regions. Furthermore, [3H]muscimol binding in vinconate-treated gerbils exhibited a significant increase compared with that in sham-operated animals. These results show that opioid and N-methyl-D-aspartate receptors are very sensitive to transient cerebral ischemia, whereas gamma-aminobutyric acidA receptors are particularly resistant. They also suggest that vinconate has a potent protective effect against the alterations of opioid and N-methyl-D-aspartate receptors. These findings might be of interest in relation to the mechanism of ischemic neuronal damage.
Murakami
F
F
Pharmacological Research Laboratory, Tokyo Tanabe Co., Ltd., Japan.
Araki
T
T
Kanai
Y
Y
Kato
H
H
Kogure
K
K
D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D016291:Dizocilpine Maleate / Q000378:metabolism*; D005849:Gerbillinae; D002546:Ischemic Attack, Transient / Q000378:metabolism*; D008297:Male; D009118:Muscimol / Q000378:metabolism*; D009270:Naloxone / Q000378:metabolism*; D011869:Radioligand Assay; D018079:Receptors, GABA / Q000187:drug effects; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects; D011957:Receptors, Opioid / Q000187:drug effects; D014748:Vinca Alkaloids / Q000494:pharmacology*
D018079:Receptors, GABA; D016194:Receptors, N-Methyl-D-Aspartate; D011957:Receptors, Opioid; D014748:Vinca Alkaloids; D009118:Muscimol; D009270:Naloxone; D016291:Dizocilpine Maleate; C038627:vinconate