TY - JOUR
T1 - Hypertension downregulates the expression of brain-derived neurotrophic factor in the ischemia-vulnerable hippocampal CA1 and cortical areas after carotid artery occlusion
AU - Lee, Tsong Hai
AU - Yang, Jen Tsung
AU - Kato, Hiroyuki
AU - Wu, June Hsieh
PY - 2006/10/20
Y1 - 2006/10/20
N2 - We studied the effect of hypertension on brain damage and brain-derived neurotrophic factor (BDNF) expression in the hippocampal formation and cerebral cortex after permanent occlusion of bilateral common carotid arteries (CCA). Two groups of rats were used, including normotensive Wistar-Kyoto (WKY) rat and spontaneous hypertensive rat (SHR). Each group contained sham operation, 1 week and 4 weeks after bilateral CCA occlusion (n = 5-10 in each time point). The blood pressure showed a significant elevation in WKY rats from 1 h after operation to 4 weeks before sacrifice (P < 0.05), but was not changed in SHR (P > 0.05). However, rectal temperature showed no significant change after operation in WKY rat and SHR (P > 0.05) and showed no significant difference at any time point between WKY rat and SHR (P > 0.05). Hematoxylin and eosin staining showed SHR had a significantly larger necrotic volume than WKY rats (n = 10 in each group, 6044 ± 6895 μm3 vs. 144 ± 174 μm3, P < 0.05) at 4 weeks after ischemia. In SHR, BDNF immunoreactivity and mRNA decreased significantly from 1 week to 4 weeks in both the hippocampal CA1 and cortical areas (P < 0.01) but decreased transiently in dentate gyrus. However, in WKY rats, BDNF immunoreactivity and mRNA decreased transiently at 1 week (P < 0.05) and recovered at 4 weeks after cerebral ischemia. Our study demonstrates that after bilateral CCA occlusion, preexisting hypertension may aggravate the brain injury and downregulate the expression of BDNF immunoreactivity and mRNA in the ischemia-vulnerable hippocampal CA1 and cortical areas but not in ischemia-resistant dentate gyrus.
AB - We studied the effect of hypertension on brain damage and brain-derived neurotrophic factor (BDNF) expression in the hippocampal formation and cerebral cortex after permanent occlusion of bilateral common carotid arteries (CCA). Two groups of rats were used, including normotensive Wistar-Kyoto (WKY) rat and spontaneous hypertensive rat (SHR). Each group contained sham operation, 1 week and 4 weeks after bilateral CCA occlusion (n = 5-10 in each time point). The blood pressure showed a significant elevation in WKY rats from 1 h after operation to 4 weeks before sacrifice (P < 0.05), but was not changed in SHR (P > 0.05). However, rectal temperature showed no significant change after operation in WKY rat and SHR (P > 0.05) and showed no significant difference at any time point between WKY rat and SHR (P > 0.05). Hematoxylin and eosin staining showed SHR had a significantly larger necrotic volume than WKY rats (n = 10 in each group, 6044 ± 6895 μm3 vs. 144 ± 174 μm3, P < 0.05) at 4 weeks after ischemia. In SHR, BDNF immunoreactivity and mRNA decreased significantly from 1 week to 4 weeks in both the hippocampal CA1 and cortical areas (P < 0.01) but decreased transiently in dentate gyrus. However, in WKY rats, BDNF immunoreactivity and mRNA decreased transiently at 1 week (P < 0.05) and recovered at 4 weeks after cerebral ischemia. Our study demonstrates that after bilateral CCA occlusion, preexisting hypertension may aggravate the brain injury and downregulate the expression of BDNF immunoreactivity and mRNA in the ischemia-vulnerable hippocampal CA1 and cortical areas but not in ischemia-resistant dentate gyrus.
KW - Brain-derived neurotrophic factor
KW - Cerebral ischemia
KW - Common carotid artery
KW - Immunohistochemistry
KW - In situ hybridization
UR - http://www.scopus.com/inward/record.url?scp=33749433915&partnerID=8YFLogxK
U2 - 10.1016/j.brainres.2006.07.117
DO - 10.1016/j.brainres.2006.07.117
M3 - 文章
C2 - 16962081
AN - SCOPUS:33749433915
SN - 0006-8993
VL - 1116
SP - 31
EP - 38
JO - Brain Research
JF - Brain Research
IS - 1
ER -