title: Acute and chronic effects of lithium on BDNF and GDNF mRNA and protein levels in rat primary neuronal, astroglial and neuroastroglia cultures.
abstract: OBJECTIVE
  The neuroprotective effect of lithium has been attributed to its therapeutic action. However, the role of glial cells particularly astrocytes, and the possible interactions between neurons and astrocytes in neuroprotective effects of lithium have been disregarded. Thus, the aim of this study was to evaluate the direct effects of lithium on brain derived neurotrophic factor (BDNF) and glial cell line derived neurotrophic factor (GDNF) in rat primary neuronal, astrocytes, and mixed neuro-astroglial cultures to assess the possible effects of lithium on astrocytes and neuro-astroglia interactions.
  
  
  METHODS
  Rat primary astrocyte, neuronal and mixed neuro-astrocyte cultures were prepared from cortices of 18-day embryos. Cell cultures were exposed to lithium (1 mM) or vehicle for 1 day (acute) or 7 days (chronic). BDNF and GDNF mRNA and protein levels were determined by RT-PCR and ELISA, respectively.
  
  
  RESULTS
  Chronic but not acute lithium treatment increased intracellular BDNF and GDNF protein levels in rat primary neuronal and astrocyte cultures, respectively (P<0.05). However, chronic lithium treatment had no significant effect on intracellular BDNF protein level in astrocyte and mixed neuron-astrocyte cultures or GDNF protein levels in mixed neuron-astrocyte culture. Furthermore, acute and chronic lithium treatment had no significant effect on mRNA and extracellular BDNF and GDNF protein levels in three studied cultures.
  
  
  CONCLUSIONS
  Present study showed that chronic lithium treatment affected neurotrophins both in neurons and astrocytes in a cell-type specific manner with no effect on neuron-astrocyte interactions. The findings of this study also highlighted the importance of astrocytes as drug targets involved in the neuroprotective action of lithium.
authors.affiliation: Department of Pharmacology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran ; Department of Neuroscience, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Emamghoreishi
authors.affiliation: Department of Pharmacology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Mojtaba
authors.initials: M
authors.lastname: Keshavarz
authors.affiliation: Department of Pharmacology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Ali Akbar
authors.initials: AA
authors.lastname: Nekooeian
keywords: Astrocytes; BDNF; Culture; GDNF; Lithium; Neuro-astroglial; Neurons