Effect of N-acetylcysteine treatment on ischaemic neuronal damage in the rat trigeminal ganglion

We studied the influence of pre-and post-ischaemic treatment with a free ra dical scavenger, N-acetylcysteine (NAC), on trigeminal ganglia neurons in t he rat after 30 min global brain ischaemia. Three experimental groups of an imals a) ischaemic non-treated, b) preischaemically and c) postischaemicall y NAG-treated (400 mg/kg i. p.) rats were used in this study. Changes in th e ganglion neurons after ischaemia with 1-3 days survival were studied by l ight and electron microscopy. Light microscopy in non-treated animals at 3 days post ischaemia revealed some large A-type chromatolytic neurons with d ark eccentric nuclei. Small B-ts pe neurons showed heavy vacuolation. Elect ron microscopy after 3 days survival revealed changes in both types of neur ons, characterized by a peripheral location of endoplasmic reticulum, eccen tric nuclei and segregated nucleoli. In the cytoplasm of A-type neurons, fo rmation of peripheral vacuoles, lamellar myelinoid bodies and a higher amou nt of lipofuscin granules were noticed. Numerous B-cells displayed degenera tive changes with an extensive mitochondrial vacuolation. Pre- and post-isc haemic NAC administration reduced the occurrence of degenerating B-cells (7 .4% or 8.9 %, respectively) compared with ischaemic non-treated rats (14.5% ). This protective effect of NAC application may have a value in the treatm ent of some cerebrovascular diseases.