Energy metabolism in delayed neuronal death of CA1 neurons of the hippocampus following transient ischemia in the gerbil

1986 ◽  
Vol 1 (4) ◽  
pp. 263-278 ◽  
Author(s):  
Hajime Arai ◽  
Janet V. Passonneau ◽  
W. David Lust
2004 ◽  
Vol 92 (5) ◽  
pp. 2960-2967 ◽  
Author(s):  
Hong Xing ◽  
Aryan Azimi-Zonooz ◽  
C. William Shuttleworth ◽  
John A. Connor

In addition to their role in signaling, Ca2+ ions in the endoplasmic reticulum also regulate important steps in protein processing and trafficking that are critical for normal cell function. Chronic depletion of Ca2+ in the endoplasmic reticulum has been shown to lead to cell degeneration and has been proposed as a mechanism underlying delayed neuronal death following ischemic insults to the CNS. Experiments here have assessed the relative content of ryanodine receptor-gated stores in CA1 neurons by measuring cytoplasmic Ca2+ increases induced by caffeine. These measurements were performed on CA1 neurons, in slice, from normal gerbils, and compared with responses from this same population of neurons 54–60 h after animals had undergone a standard ischemic insult: 5-min bilateral occlusion of the carotid arteries. The mean amplitude of responses in the postischemic population were less than one-third of those in control or sham-operated animals, and 35% of the neurons from postischemic animals showed very small responses that were ∼10% of the control population mean. Refilling of these stores after caffeine challenges was also impaired in postischemic neurons. These observations are consistent with our earlier finding that voltage-gated influx is sharply reduced in postischemic in CA1 neurons and the hypothesis that the resulting depletion in endosomal Ca2+ is an important cause of delayed neuronal death.


1997 ◽  
Vol 17 (9) ◽  
pp. 967-976 ◽  
Author(s):  
Carol K. Petito ◽  
Jorge Torres-Munoz ◽  
Brenda Roberts ◽  
John-Paul Olarte ◽  
Thaddeus S. Nowak ◽  
...  

Apoptosis is an active, gene-directed process of cell death in which early fragmentation of nuclear DNA precedes morphological changes in the nucleus and, later, in the cytoplasm. In ischemia, biochemical studies have detected oligonucleosomes of apoptosis whereas sequential morphological studies show changes consistent with necrosis rather than apoptosis. To resolve this apparent discrepancy, we subjected rats to 10 minutes of transient forebrain ischemia followed by 1 to 14 days of reperfusion. Parameters evaluated in the CA1 region of the hippocampus included morphology, in situ end labeling (ISEL) of fragmented DNA, and expression of p53. Neurons were indistinguishable from controls at postischemic day 1 but displayed cytoplasmic basophilia or focal condensations at day 2; some neurons were slightly swollen and a few appeared normal. In situ end labeling was absent. At days 3 and 5, approximately 40 to 60% of CA1 neurons had shrunken eosinophilic cytoplasm and pyknotic nuclei, but only half of these were ISEL. By day 14, many of the necrotic neurons had been removed by phagocytes; those remaining retained mild ISEL. Neither p53 protein nor mRNA were identified in control or postischemic brain by in situ hybridization with riboprobes or by northern blot analysis. These results show that DNA fragmentation occurs after the development of delayed neuronal death in CA1 neurons subjected to 10 minutes of global ischemia. They suggest that mechanisms other than apoptosis may mediate the irreversible changes in the CA1 neurons in this model.


1989 ◽  
Vol 49 ◽  
pp. 266
Author(s):  
Takeshi Mushiroi ◽  
Kiyoshi Kimura ◽  
Tonhiki Yoshimine ◽  
Toru Hayakawa ◽  
Heitaro Mogami

1991 ◽  
Vol 11 (5) ◽  
pp. 819-823 ◽  
Author(s):  
Hitoshi Imon ◽  
Akira Mitani ◽  
Yasushi Andou ◽  
Tatsuru Arai ◽  
Kiyoshi Kataoka

It has been proposed that neuronal hyperexcitability during postischemic chronic stage mediates delayed neuronal death in the hippocampal CA1 region. In the present study, multiple-unit spike discharges were continuously recorded from hippocampal CA1 neurons of the awake Mongolian gerbil for 5 days after 5 min of ischemia. Before ischemia, CA1 neurons showed burst-like spike discharges (so-called complex spikes). Spike discharges disappeared 8–40 s after the onset of 5-min ischemia and reappeared 5–30 min after recirculation. The frequency of discharges gradually increased but did not return to the preischemic level. The amplitude of the spike discharges was smaller than that recorded before ischemia and the number of spikes composing the burst-like discharges diminished. CA1 neurons did not show any hyperexcitability for 5 days. However, histological examinations revealed widespread neuronal death in the CA1 region. These results indicate that the delayed neuronal death in the hippocampal CA1 region is induced without postischemic neuronal hyperexcitability.


2013 ◽  
Vol 33 (8) ◽  
pp. 1173-1181 ◽  
Author(s):  
María Irene Ayuso ◽  
Emma Martínez-Alonso ◽  
Cristina Cid ◽  
Maria Alonso de Leciñana ◽  
Alberto Alcázar

Transient brain ischemia induces an inhibition of translational rates and causes delayed neuronal death in selective regions and cognitive deficits, whereas these effects do not occur in resistant areas. The translational repressor eukaryotic initiation factor (elF) 4E-binding protein-2 (4E-BP2) specifically binds to eIF4E and is critical in the control of protein synthesis. To link neuronal death to translation inhibition, we study the eIF4E association with 4E-BP2 under ischemia reperfusion in a rat model of transient forebrain ischemia. Upon reperfusion, a selective neuronal apoptosis in the hippocampal cornu ammonis 1 (CA1) region was induced, while it did not occur in the cerebral cortex. Confocal microscopy analysis showed a decrease in 4E-BP2/eIF4E colocalization in resistant cortical neurons after reperfusion. In contrast, in vulnerable CA1 neurons, 4E-BP2 remains associated to eIF4E with a higher degree of 4E-BP2/eIF4E colocalization and translation inhibition. Furthermore, the binding of a 4E-BP2 peptide to eIF4E induced neuronal apoptosis in the CA1 region. Finally, pharmacological-induced protection of CA1 neurons inhibited neuronal apoptosis, decreased 4E-BP2/eIF4E association, and recovered translation. These findings documented specific changes in 4E-BP2/eIF4E association during ischemic reperfusion, linking the translation inhibition to selective neuronal death, and identifying 4E-BP2 as a novel target for protection of vulnerable neurons in ischemic injury.


1987 ◽  
Vol 3 (3) ◽  
pp. 227-232 ◽  
Author(s):  
Hiroyuki ARAI ◽  
Koji MACHII ◽  
Takehide TSUDA ◽  
Kyuya KOGURE ◽  
Takao WATANABE ◽  
...  

2009 ◽  
Vol 29 (6-7) ◽  
pp. 871-878 ◽  
Author(s):  
Viera Danielisová ◽  
Miroslav Gottlieb ◽  
Miroslava Némethová ◽  
Petra Kravčuková ◽  
Iveta Domoráková ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document