Hippocampus development

Reverse engineering of a CNS genetic network using a linear model. Experimental gene expression data (circles development and injury), and simulation using a linear model (lines). Dotted line spinal cord, starting at day —11 (embryonic day 11). Solid line hippocampus development, starting at day... 

Song HJ, Stevens CF, Gage FH. Neural stem cells from the hippocampus develop essential properties of functional CNS neurons. Nat Neurosci 2002, 5, 438-445. 

Recently, there has been a growth of interest in the development of in vitro methods for measuring toxic effects of chemicals on the central nervous system. One approach has been to conduct electrophysiological measurements on slices of the hippocampus and other brain tissues (Noraberg 2004, Kohling et al. 2005). An example of this approach is the extracellular recording of evoked potentials from neocortical slices of rodents and humans (Kohling et al. 2005). This method, which employs a three-dimensional microelectrode array, can demonstrate a loss of evoked potential after treatment of brain tissue with the neurotoxin trimethyltin. Apart from the potential of in vitro methods such as this as biomarkers, there is considerable interest in the use of them as alternative methods in the risk assessment of chemicals, a point that will be returned to in Section 16.8. 

If a subconvulsive stimulus is applied, generally in rats, at regular intervals, e.g. daily for some two weeks to a specific brain area, especially the amygdala or hippocampus, then eventually full localised (partial) or secondary generalised seizures develop. A similar effect can be obtained by the repeated localised injection of subconvulsive doses of some convulsants. The ability of a drug to reduce the kindled seizure itself may be indicative of value in partial seizure but if it slows the actual development of kindling that may indicate some ability to retard epileptogenesis. 

Altmann L,Gutowski M, Wiegand H. 1994. Effects of maternal lead exposure on functional plasticity in the visual cortex and hippocampus of immature rats. Develop Brain Res 81 50-56. 

The long-term consequences of neonatal exposure to triethyllead were examined with respect to the development of the central nervous system of rats138. The studies of the developmental exposure to triethyllead lead to the conclusion that this compound causes permanent hippocampus damage (neurotoxicity) in rats. 

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