Neuronal plasticity in the striatum after global forebrain ischemia in rats
Field:	Other
Authors:	Larsson, Elin Kokaia, Zaal Lindvall, Olle
Address of presenting author:	Section of Restorative Neurology Wallenberg Neuroscience Centre Sölvegatan 17 223 62 Lund
E-mail:	elin.larsson@neurol.lu.se
Phone:	046-2220548
Fax:	046-2220560
Text of abstract:	The neurons in the striatum have different susceptibility to ischemic damage. While the GABAergic projection neurons (DARPP-32 positive) are sensitive to the insult, the cholinergic interneurons (ChAT and TrkA positive) are resistant. The aim of this study was to explore the different vulnerability of neurons in the striatum after 30 minutes of global forebrain ischemia following 48 hours, 1 week and 4 weeks of reperfusion. The ischemic insult resulted in a robust loss of the DARPP-32 immunopositive neurons, predominantly at caudal levels, already after 48 hours of reperfusion. In more rostral levels the loss of projection neurons was restricted to the dorsolateral area of striatum. The ChAT immunopositive neurons on the other hand, not only survived the insult, but also showed a marked increase in number after 4 weeks of reperfusion. This increase in number of ChAT positive neurons was also accompanied by an increase in the number of TrkA immunopositive neurons. The increase in number of ChAT and TrkA immunopositive neurons is probably due to an increase of the respective protein levels. The number of TrkA positive neurons was also increased 48 hours after the ischemic insult, which coincides with the upregulation of p75 immunoreactivity in the cholinergic neurons. This increase of TrkA immunoreactivity might be a neuroprotective response to counteract the p75 receptor upregulation, which under some circumstances is known to lead to apoptosis. The GABAergic interneurons in the striatum are currently being quantified.
Keywords:	global forebrain ischemia, striatum, interneurons, projection neurons

Created 2000-03-16