TY - JOUR
T1 - Sustained increase of methylguanidine in rats after amygdala or hippocampal kindling
AU - Shimizu, Yukito
AU - Morimoto, Kiyoshi
AU - Kuroda, Shigetoshi
AU - Mori, Akitane
PY - 1995/5
Y1 - 1995/5
N2 - Methylguanidine (MG) and guanidinoacetic acid (GAA) are known to be endogenous convulsants in the mammalian brain. We have reported previously that MG and GAA concentrations were significantly elevated bilaterally in the amygdala (AM) 7 and 28 days after completion of AM kindling. In the present study, we investigated regional changes in MG and GAA in (1) AM-kindled rat brain 3 months after completion of kindling and (2) hippocampal (HIPP)-kindled rat brain 7 and 28 days after completion of kindling, using high-performance liquid chromatography. MG was increased significantly in the kindled AM 3 months after completion of AM kindling (76%, P < 0.05). Significant increases in MG levels were also found 7 and 28 days after completion of HIPP kindling (124%, P < 0.025 and 110%, P < 0.05, respectively) in the left AM, ipsilateral to the kindled site. GAA increased significantly (93%, P < 0.025) only in the left AM, ipsilateral to the kindled site, 7 days after completion of HIPP kindling. These results, together with our previous data, indicate that long-lasting increases of MG occur in the AM regardless of kindled foci, and may be important in producing neuronal hyperexcitability in kindled epileptogenesis.
AB - Methylguanidine (MG) and guanidinoacetic acid (GAA) are known to be endogenous convulsants in the mammalian brain. We have reported previously that MG and GAA concentrations were significantly elevated bilaterally in the amygdala (AM) 7 and 28 days after completion of AM kindling. In the present study, we investigated regional changes in MG and GAA in (1) AM-kindled rat brain 3 months after completion of kindling and (2) hippocampal (HIPP)-kindled rat brain 7 and 28 days after completion of kindling, using high-performance liquid chromatography. MG was increased significantly in the kindled AM 3 months after completion of AM kindling (76%, P < 0.05). Significant increases in MG levels were also found 7 and 28 days after completion of HIPP kindling (124%, P < 0.025 and 110%, P < 0.05, respectively) in the left AM, ipsilateral to the kindled site. GAA increased significantly (93%, P < 0.025) only in the left AM, ipsilateral to the kindled site, 7 days after completion of HIPP kindling. These results, together with our previous data, indicate that long-lasting increases of MG occur in the AM regardless of kindled foci, and may be important in producing neuronal hyperexcitability in kindled epileptogenesis.
KW - Amygdala
KW - Guanidino compounds
KW - Hippocampus
KW - Kindling
KW - Methylguanidine
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U2 - 10.1016/0920-1211(94)00004-G
DO - 10.1016/0920-1211(94)00004-G
M3 - Article
C2 - 7641671
AN - SCOPUS:0029071847
VL - 21
SP - 11
EP - 17
JO - Journal of Epilepsy
JF - Journal of Epilepsy
SN - 0920-1211
IS - 1
ER -