Cortical Ablation Induces Time-Dependent Changes in Rat Pituitary Somatotrophs and Upregulates Growth Hormone Receptor Expression in the Injured Cortex
2014
Аутори:
Lavrnja, IrenaAjdžanović, Vladimir
Trifunović, Svetlana
Savić, Danijela
Milošević, Verica
Stojiljkovic, Mirjana
Peković, Sanja
Тип документа:
Чланак у часопису (Објављена верзија)
Метаподаци
Приказ свих података о документуАпстракт:
The pituitary appears to be vulnerable to brain trauma, and its
dysfunction is a common feature after traumatic brain injury. The role
of pituitary growth hormone (GH) in brain repair after injury has been
envisaged, but more studies must be performed to understand completely
the importance of GH in these processes. Because some of the
neuroprotective effects of GH are mediated directly through the GH
receptor (GHR), we examined GHR expression in the rat cerebral cortex
after sensorimotor cortex ablation. RT-PCR, immunohistochemistry, and
double immunofluorescence had been performed to analyze the correlation
between GHR expression in the injured cortex and activity of GH cells in
the pituitary. Our results showed that the volume of GH-immunopositive
cells was reduced at days 2 and 7 postsurgery (dps), and volume density
of GH cells was significantly decreased at 14 dps, all compared with
appropriate sham controls. At 30 dps all investigated parameters had
returned to control level. In the injured cortex, GHR expression was
transiently upregulated. Increased GHR immunoreactivity was observed in
reactive astrocytes at 7 and particularly at 14 dps. In neuronal cells,
an increase of GHR immunoreactivity was seen in neuronal cell bodies and
well-defined primary dendrites at 14 and especially at 30 dps. The
results presented here suggest that, during recovery from brain injury,
changes in activity of pituitary GH cells result in upregulation of GHR
that may have a role in neuronal arborization and glial proliferation in
the injured cortex. (C) 2014 Wiley Periodicals, Inc.
Кључне речи:
growth hormone; glia scar; pituitary gland; traumatic brain injury; growth hormone receptorИзвор:
Journal of Neuroscience Research, 2014, 92, 10, 1338-1349
DOI: 10.1002/jnr.23408
ISSN: 1097-4547