Memory improvement in ibotenic acid induced model rats by extracts of Scutellaria baicalensis.
BACKGROUND
Scutellaria baicalensis Georgi (Labiatae) extracts have been used as traditional Korean medicine, to treat cerebral ischemia in addition to bacterial infection and inflammatory diseases.


OBJECTIVE
The improvement effect on learning and memory by the administration of Scutellaria baicalensis extracts was evaluated and the underlying mechanisms were investigated.


METHODS
Memory behavior was tested by the passive avoidance test and Y-maze test. We also investigated the cells expressing neuronal markers related to memory processes by immunofluorescence staining analysis in memory deficient animal model (Ibo model) rats and in hippocampal progenitor cells.


RESULTS
We found neuronal cells immunoreactive to choline acetyltransferase (ChAT), a marker for cholinergic neurons were increased in the hippocampus, while cells producing GABA and glutamate were not after 30 mg/kg Scutellaria baicalensis administration. Futhermore, Scutellaria baicalensis extracts enhanced the survival of a hippocampal progenitor cell line, HiB5 and its differentiation to ChAT immunoreactive cells. The increased expression of memory related neurotransmitter, NMDA receptor and a reduction of activated microglia in the hippocampus were also observed in the Ibo model when administrated Scutellaria baicalensis extracts.


CONCLUSIONS
These results imply that Scutellaria baicalensis has significant neuroprotective effects in the Ibo model.
Heo
Hwon
H
Department of Biology, Kyunghee University, 1 Hoegi-dong, Dongdaemun-gu, Seoul 130-701, Republic of Korea.
Shin
Yongsung
Y
Cho
Woohee
W
Choi
YoonSeok
Y
Kim
Hocheol
H
Kwon
Yunhee Kim
YK
D000818:Animals; D002470:Cell Survival; D018690:Excitatory Amino Acid Agonists / Q000009:adverse effects; D006624:Hippocampus / Q000187:drug effects / Q000473:pathology; D007051:Ibotenic Acid / Q000009:adverse effects; D007858:Learning / Q000187:drug effects*; D008297:Male; D018782:Maze Learning; D008568:Memory / Q000187:drug effects*; D017628:Microglia / Q000187:drug effects; D023421:Models, Animal; D018696:Neuroprotective Agents / Q000494:pharmacology* / Q000627:therapeutic use; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use; D018517:Plant Roots; D051381:Rats; D017207:Rats, Sprague-Dawley; D018091:Receptors, AMPA / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism; D031364:Scutellaria baicalensis
D018690:Excitatory Amino Acid Agonists; C120997:NR2A NMDA receptor; D018696:Neuroprotective Agents; D010936:Plant Extracts; D018091:Receptors, AMPA; D016194:Receptors, N-Methyl-D-Aspartate; C499814:Scutellaria baicalensis extract; D007051:Ibotenic Acid; C104722:glutamate receptor ionotropic, AMPA 2