Figure 3. Four micrographs of Nissl-stained sections from slices taken to show (A) control (no insult);(B) pretreatment with 27 [micro sign]M L-nitroarginine methyl ester (L-NAME);(C) pretreatment with 27 [micro sign]M 7-nitroindozole (7-NI); and (D) pretreatment with 27 [micro sign]M L-nitroarginine (L-NOArg). Slices were sampled randomly at the end of the 60 min of reperfusion recovery in normoxic artificial cerebrospinal fluid. Qualitatively, L-NAME (B) and 7-NI pretreatment (C) prevented oxygen deprivation-induced shrinking of Nissl-stained neuronal nuclei, and also cell swelling, as seen in A and D. The scale bar (20 [micro sign]m) is the same for all micrographs.