Exogenous brain-derived neurotrophic factor (BDNF) can regulate behavioral sensitization and conditioned place preference (CPP) when animals are exposed to repeated cocaine administration.
The incubation of a radiosensitive clone with the exogenous bovine brain ganglioside GM1 significantly increases the proportion of radioresistant cells and suppresses its metastatic potential, while the inhibition of the endogenous gangliosides synthesis in the radioresistant cell line M4Be increases the proportion of radiosensitive cells.
To test this prediction for PKA signaling, we used a pharmacogenetic approach based on Rs1, a modified Gαs-coupled GPCR sensitive to a small, exogenous, blood-brain-barrier permeable ligand (Srinivasan et al., 2003).
The upregulated expression levels of those target genes were reported to be related with the decreased permeability of BBB [44 50], which could facilitate the transportation of other exogenous substances into brain.
Negative and positive controls were provided by untreated castrates and by castrates treated with exogenous T. Two brain estrogen-sensitive responses, the volume of the POM defined by aromatase-immunoreactive staining and the density of vasotocin fibers in the POM were also investigated.
In the brain, exogenous HMGB1 induces the release of pro-inflammatory cytokines (Ref. 86) and excitatory amino acids (such as glutamate) (Ref. 87), induces fever (Ref. 88), and exacerbates cerebral ischaemic injury (Ref. 89).
The protocols were tested using increasing in vitro transcription time or PCR cycle number, with a special look at 5 transcripts: 3 endogenous and 1 exogenous transcripts in brain and ovary, 1 endogenous transcript in developing embryos.
P-glycoprotein (Pgp) function in the blood-brain barrier hampers the entry of exogenous progesterone into the brain [ 35], whereas C6 tumours do not express Pgp (personal observations).
