Immunohistochemical changes in vulnerable rat brain regions after reversible global brain ischaemia

Abstract

Human global ischaemia was simulated in adult rats by inducing 20 min brain ischaemia and 60 min post-ischaemic recirculation. Immunohistochemical expression of MMP-9, TIMP-3, Bax and Bcl-2, and DNA fragmentation (with the TUNEL reaction) were investigated. The morphological data showed different neuronal responses in the hippocampus compared with the cerebral and cerebellar cortices. MMP-9 immunoreactivity was different in the hippocampus, particularly in dentate gyrus and the CA1 region, compared with these cortices. Negative TIMP-3 staining in ischaemic hippocampal neurons may indicate a loss of its inhibitory activity on MMP-9 that could enhance cell death. Bcl-2 down regulation, Bax positivity and TUNEL+ type II cells in the dentate gyrus granular layer could be responsible for induction of apoptotic death in CA1 hippocampal pyramidal cells via loss of fibre input. Results suggest differential behaviours of neural cells after 60 min reperfusion.

RNA interference-mediated downregulation of Beclin1 attenuates cerebral ischemic injury in rats

“…As previously reported, an increase in neurogenesis following ischemia has been considered to be necessary for functional recovery after stroke [19,20] . Beclin1-dependent autophagy has been associated with neurogenesis in several models [21,22] .…”

Neuroprotective effects of lotus seedpod procyanidins on extremely low frequency electromagnetic field-induced neurotoxicity in primary cultured hippocampal neurons

“…In order to investigate their roles in regulating mitochondrial permeability, recent studies show functions of these proteins in control of mitochondrial fission and fusion [40]. The level of Bcl-2 protein decreases in brain ischemia [41] and overexpression of prosurvival proteins Bcl-2 family can compete against cerebral ischemia [42]. The neuroprotective mechanism involves maintaining mitochondrial function [43].…”

Role of Continuous High Thoracic Epidural Anesthesia in Hippocampal Apoptosis after Global Cerebral Ischemia in Rats

“…Neuronal apoptosis in the hippocampal CA1 region was assessed by TUNEL staining, using an in situ cell death detection kit (TMR green, Roche, Mannheim, Germany). The brain sections at 24 hours after reperfusion (sham, n=5; GCI, n=7; HTEA, n=5) were used to perform immunohistochemistry as described [27]. The primary antibodies were: rabbit polyclonal antibody against PARP (1:200, ab6079, Abcam), Bcl-2 (1:100, BA0412, Boster) or Bax (1:100, BA0315-1, Boster).…”