Ibotenate-induced cell death in the hypothalamic paraventricular nucleus: differential susceptibility of magnocellular and parvicellular neurons.
Injections of ibotenic acid (IBO) (0.5-2.0 micrograms) were made unilaterally into the hypothalamic paraventricular nucleus (PVN) of Sprague-Dawley rats. A distinct loss of parvicellular neurons was evident at all dosages examined, and cell death appeared uniform throughout the injection region at doses of 1.0 micrograms or greater. In contrast, magnocellular neurons were present following injections of all dosages, with a slight loss of neurons evident only at 2.0 micrograms doses. Magnocellular neurons killed at 2.0 micrograms doses were primarily vasopressinergic. Neuropeptide content per se was not the critical determinant of susceptibility to IBO, as parvicellular oxytocin neurons were destroyed by low to moderate doses of IBO. The results suggest that IBO may be useful neurotoxin with which to investigate differential connectional and functional properties of parvicellular and magnocellular PVN neurons.
D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D005260:Female; D007051:Ibotenic Acid / Q000494:pharmacology*; D008297:Male; D010080:Oxazoles / Q000494:pharmacology*; D010286:Paraventricular Hypothalamic Nucleus / Q000166:cytology / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains
D010080:Oxazoles; D007051:Ibotenic Acid