Anomalous expression of microtubule-associated protein 1B in the hippocampus and cortex of aged rats treated with pentylenetetrazole
| Autor: | Dieter Platt, Christof Kessler, H Schmoll, Barbara Fischer, R Neubig, Aurel Popa-Wagner |
|---|---|
| Rok vydání: | 1999 |
| Předmět: |
Aging
medicine.medical_specialty Time Factors Transcription Genetic Central nervous system In situ hybridization Hippocampal formation Biology Hippocampus Rats Sprague-Dawley Retrosplenial cortex Seizures Internal medicine medicine Animals RNA Messenger In Situ Hybridization Cerebral Cortex Messenger RNA General Neuroscience Dentate gyrus Gene Expression Regulation Developmental Blotting Northern Entorhinal cortex Immunohistochemistry Rats medicine.anatomical_structure Endocrinology Organ Specificity Cerebral cortex Pentylenetetrazole Female Microtubule-Associated Proteins |
| Zdroj: | Neuroscience. 94:395-403 |
| ISSN: | 0306-4522 |
| DOI: | 10.1016/s0306-4522(99)00204-3 |
| Popis: | The aim of the present study was to assess the age-dependent response of microtubule-associated protein 1B, a plasticity-associated protein deriving from a late gene, following administration of an epileptogenic stimulus. The effect of a single administration of the convulsant pentylenetetrazole on microtubule-associated protein 1B expression in the hippocampal formation and cortex of three-, 18- and 28-month-old rats was assessed using northern blot analysis, in situ hybridization and immunohistochemistry. In three-month-old rats, we detected initial increases in microtubule-associated protein 1B messenger RNA at 15 h following pentylenetetrazole administration in the granule cells of the dentate gyrus, in the CA3 region of the hippocampus and in layers II/III of the entorhinal cortex, and these reached a maximum at 44 h. However, in the hippocampus and cortex of 18-month-old rats, the peak occurred at 15 h, and in the brains of 28-month-old rats a blunted peak was reached at 3 h. Pentylenetetrazole treatment in young rats resulted in a robust induction of microtubule-associated protein 1B immunoreactivity in the granule cells of the dentate gyrus and in layers II/III of the entorhinal cortex, but also produced a large decrease in the retrosplenial cortex. However, following pentylenetetrazole treatment in older rats, the granule cells of the dentate gyrus were nearly devoid of microtubule-associated protein 1B immunoreactivity, whereas the retrosplenial cortex showed no changes at all, and the entorhinal cortex had an expression pattern similar to that of young rats. Aberrant immunolabeling of microtubule-associated protein 1B occurred in cortical layer VI of the aged rats where, unlike in young rats, there was heavy staining of neuronal somata. These results suggest that the regulation of the plasticity-associated protein microtubule-associated protein 1B is altered in the ageing rat brain, with the peak of expression shifted to earlier times in 18-month-old rats and blunted, variable increases at even earlier times in 28-month-old rats. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect