Epilepsy & hyperthermia in rats

Many mild preconditioning stress conditions, including physical and metabolic injuries, increase the resistance of neurons to subsequent more severe stresses of the same or different type. This “tolerance phenomenon” lasts one to several weeks, providing a unique opportunity to investigate endogenous neuroprotective mechanisms. The aim of this study was to find a physiological and easily applicable preconditioning stimulus able to confer protection against convulsant-induced neuronal damage and seizures. We found that moderate transient hyperthermic preconditioning markedly reduced kainic-acid-induced neuronal cell loss and attenuated susceptibility to bicuculline-induced seizures. Prevention of cell damage (approximately 50%) was efficient both in vitro in organotypic hippocampal slice cultures and in vivo in adult rats. This protection lasted about 1 week and peaked 3 to 5 days after pretreatment. Unraveling the mechanisms of heat shock preconditioning-induced protection against epilepsy should lead to the development of new therapeutic strategies. (via.)

BDNF, hyperlexia, hypergraphia, seizures…

Just some loosely connected neuro-things I wanted to save somewhere.

  • Notably without citation, Wikipedia claims BDNF is also expressed in the retina, the central nervous system, motor neurons, the kidneys, and the prostate (aside from just the hippocampus and cerebral cortex). (via.)
  • BDNF knockingout in mice affects coordination, balance, hearing, taste, and breathing. “Knockout mice also exhibit cerebellar abnormalities and an increase in the number of sympathetic neurons.” (via.)
  • BDNF is increased by prolonged seizures, and important to GABA pathways. (via.)
  • Hypergraphia, a condition which afflicts individuals with a compulsive desire to write, is associated with temporal lobe epilepsy… and quite a few interesting characters have had it. (via.)
  • Hyperlexia, the extreme variety of a compulsion to read, may be caused by a “cerebral infarction in the left anterior cingulate cortex and corpus callosum.” (via.)
  • Temporal lobe epileptics are often hyposexual. (via.)

What’s BDNF & substance p got to do with eczema?

Per Wikipedia BDNF is…

BDNF acts on certain neurons of the central nervous system and the peripheral nervous system, helping to support the survival of existing neurons, and encourage the growth and differentiation of new neurons and synapses.

So I ran across this little interesting tidbit that I’ll want to follow up on later, if I happen to remember to. That is that apparently elevated levels of BDNF and Substance P (involved in nociception/pain perception) is involved in eczema? Per Substance P’s Wikipedia:

High levels of BDNF and Substance P have been found associated with increased itching in eczema.[27][28]

Interestingly also, apparently naked mole rats lack substance p altogether.

Totally unrelated, but also unusual… BDNF is found to be increased after prolonged seizure activity.