Serotonin neurones have anticonvulsant effects and reduce seizure-related mortality

Researchers who examined the effect of eliminating serotonin neurones on seizures and mortality in mice have found that mice that lacked > 99% of serotonin neurones had a lower seizure threshold and increased seizure-related mortality. The mice that died stopped breathing without recovery, whereas cardiac activity continued before the terminal event. 

Respiratory failure is an important contributor to the pathophysiology of SUDEP, and serotonin (5‐HT) system dysfunction may be involved. Given that SUDEP often occurs in association with generalised seizures, some mechanisms causing death in our model might be shared with those leading to SUDEP. This model may help determine the relationship between seizures, 5‐HT system dysfunction, breathing and death, which may lead to novel ways to prevent SUDEP.

Buchanan G, Murray M, Hayek N, Richerson G. Serotonin neurones have anticonvulsant effects and reduce seizure‐induced mortality.  J Physiol August 2014 ; e-pub August 8, 2014, doi:10.1113/jphysiol.2014.277574
http://www.ncbi.nlm.nih.gov/pubmed/?term=Buchanan+sudep+mice