Functional integration of new hippocampal neurons following insults to the adult brain is determined by characteristics of pathological environment.
(2011) In Experimental Neurology 229(2). p.484-493- Abstract
- We have previously shown that following severe brain insults, chronic inflammation induced by lipopolysaccharide (LPS) injection, and status epilepticus, new dentate granule cells exhibit changes of excitatory and inhibitory synaptic drive indicating that they may mitigate the abnormal brain function. Major inflammatory changes in the environment encountering the new neurons were a common feature of these insults. Here, we have asked how the morphology and electrophysiology of new neurons are affected by a comparably mild pathology: repetitive seizures causing hyperexcitability but not inflammation. Rats were subjected to rapid kindling, i.e., 40 rapidly recurring, electrically-induced seizures, and subsequently exposed to stimulus-evoked... (More)
- We have previously shown that following severe brain insults, chronic inflammation induced by lipopolysaccharide (LPS) injection, and status epilepticus, new dentate granule cells exhibit changes of excitatory and inhibitory synaptic drive indicating that they may mitigate the abnormal brain function. Major inflammatory changes in the environment encountering the new neurons were a common feature of these insults. Here, we have asked how the morphology and electrophysiology of new neurons are affected by a comparably mild pathology: repetitive seizures causing hyperexcitability but not inflammation. Rats were subjected to rapid kindling, i.e., 40 rapidly recurring, electrically-induced seizures, and subsequently exposed to stimulus-evoked seizures twice weekly. New granule cells were labeled 1week after the initial insult with a retroviral vector encoding green fluorescent protein. After 6-8weeks, new neurons were analyzed using confocal microscopy and whole-cell patch-clamp recordings. The new neurons exposed to the pathological environment exhibited only subtle changes in their location, orientation, dendritic arborizations, and spine morphology. In contrast to the more severe insults, the new neurons exposed to rapid kindling and stimulus-evoked seizures exhibited enhanced afferent excitatory synaptic drive which could suggest that the cells that had developed in this environment contributed to hyperexcitability. However, the new neurons showed concomitant reduction of intrinsic excitability which may counteract the propagation of this excitability to the target cells. This study provides further evidence that following insults to the adult brain, the pattern of synaptic alterations at afferent inputs to newly generated neurons is dependent on the characteristics of the pathological environment. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1937588
- author
- Wood, James LU ; Jackson, Johanna LU ; Jakubs, Katherine ; Chapman, Katie LU ; Ekdahl Clementson, Christine LU ; Kokaia, Zaal LU ; Kokaia, Merab LU and Lindvall, Olle LU
- organization
- publishing date
- 2011
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Experimental Neurology
- volume
- 229
- issue
- 2
- pages
- 484 - 493
- publisher
- Elsevier
- external identifiers
-
- wos:000291419400033
- pmid:21459089
- scopus:79952599565
- pmid:21459089
- ISSN
- 0014-4886
- DOI
- 10.1016/j.expneurol.2011.03.019
- language
- English
- LU publication?
- yes
- id
- 78a28a99-776a-4c50-97ac-5a293a276825 (old id 1937588)
- alternative location
- http://www.ncbi.nlm.nih.gov/pubmed/21459089?dopt=Abstract
- date added to LUP
- 2016-04-01 11:11:15
- date last changed
- 2022-02-10 17:23:09
@article{78a28a99-776a-4c50-97ac-5a293a276825, abstract = {{We have previously shown that following severe brain insults, chronic inflammation induced by lipopolysaccharide (LPS) injection, and status epilepticus, new dentate granule cells exhibit changes of excitatory and inhibitory synaptic drive indicating that they may mitigate the abnormal brain function. Major inflammatory changes in the environment encountering the new neurons were a common feature of these insults. Here, we have asked how the morphology and electrophysiology of new neurons are affected by a comparably mild pathology: repetitive seizures causing hyperexcitability but not inflammation. Rats were subjected to rapid kindling, i.e., 40 rapidly recurring, electrically-induced seizures, and subsequently exposed to stimulus-evoked seizures twice weekly. New granule cells were labeled 1week after the initial insult with a retroviral vector encoding green fluorescent protein. After 6-8weeks, new neurons were analyzed using confocal microscopy and whole-cell patch-clamp recordings. The new neurons exposed to the pathological environment exhibited only subtle changes in their location, orientation, dendritic arborizations, and spine morphology. In contrast to the more severe insults, the new neurons exposed to rapid kindling and stimulus-evoked seizures exhibited enhanced afferent excitatory synaptic drive which could suggest that the cells that had developed in this environment contributed to hyperexcitability. However, the new neurons showed concomitant reduction of intrinsic excitability which may counteract the propagation of this excitability to the target cells. This study provides further evidence that following insults to the adult brain, the pattern of synaptic alterations at afferent inputs to newly generated neurons is dependent on the characteristics of the pathological environment.}}, author = {{Wood, James and Jackson, Johanna and Jakubs, Katherine and Chapman, Katie and Ekdahl Clementson, Christine and Kokaia, Zaal and Kokaia, Merab and Lindvall, Olle}}, issn = {{0014-4886}}, language = {{eng}}, number = {{2}}, pages = {{484--493}}, publisher = {{Elsevier}}, series = {{Experimental Neurology}}, title = {{Functional integration of new hippocampal neurons following insults to the adult brain is determined by characteristics of pathological environment.}}, url = {{https://lup.lub.lu.se/search/files/2451033/1971361.pdf}}, doi = {{10.1016/j.expneurol.2011.03.019}}, volume = {{229}}, year = {{2011}}, }