Adaptation to single housing is dynamic: Changes in hormone levels, gene expression, signaling in the brain, and anxiety-like behavior in adult male C57Bl/6J mice.

For basic research, rodents are often housed in individual cages prior to behavioral testing. However, aspects of the experimental design, such as duration of isolation and timing of animal manipulation, may unintentionally introduce variance into collected data. Thus, we examined temporal correlates of acclimation of C57Bl/6J mice to single housing in a novel environment following two commonly used experimental time periods (7 or 14 days, SH7 or SH14).

Multiple protein kinases determine the phosphorylated state of the small heat shock protein, HSP27, in SH-SY5Y neuroblastoma cells.

In SH-SY5Y human neuroblastoma cells, the cholinergic agonist, carbachol, stimulates phosphorylation of the small heat shock protein 27 (HSP27). Carbachol increases phosphorylation of both Ser-82 and Ser-78 while the phorbol ester, phorbol-12, 13-dibutyrate (PDB) affects only Ser-82. Muscarinic receptor activation by carbachol was confirmed by sensitivity of Ser-82 phosphorylation to hyoscyamine with no effect of nicotine or bradykinin.

Hyperosmotic stress-induced caspase-3 activation is mediated by p38 MAPK in the hippocampus.

The cellular response to insult occurs by signaling via the stress-activated protein kinases, p38, and c-Jun NH(2)-terminal kinase (JNK). In the present study, we determined if hyperosmotic stress to rat hippocampal slices activates p38 and JNK and whether hyperosmolarity is a potential apoptotic stimulus in this experimental paradigm. Hyperosmotic stress, produced by addition of sorbitol to the incubation buffer, increased p38 phosphorylation; in contrast, JNK phosphorylation was not increased above control levels.

Phosphorylation of HSP27 and synthesis of 14-3-3epsilon are parallel responses to hyperosmotic stress in the hippocampus.

A stress-responsive, mitogen-activated protein kinase, p38, is activated by phosphorylation in response to adverse environmental insults. In the present study, the effects of hyperosmolarity on p38 activation and protein synthesis in the brain were examined. Hyperosmotic stress of rat brain slices, produced by addition of sorbitol to the incubation buffer, produced prolonged phosphorylation and activation of p38, most prominently in the hippocampus as compared to the cortex or cerebellum.

Remodeling of synaptic connections in the deafferented vestibular nuclear complex.

To determine if synaptic remodeling in the vestibular nuclear complex (VNC) may be involved in vestibular compensation, expressions of growth-associated protein-43 (GAP-43) and synaptosome-associated protein of 25 kDa (SNAP-25) were examined by immunoblotting and immunocytochemistry after unilateral vestibular ganglionectomy (UVG) in rats. GAP-43 expression increased bilaterally in the VNC after UVG, but more rapidly on the lesioned side, and remained high through 60 days. It was mainly associated with boutons at all survival times but was also present in some axonal processes and, at 7 days after UVG, in some somata.