Armodafinil-induced wakefulness in animals with ventrolateral preoptic lesions

Figures & data

Figure 1 Histological assessment of VLPOx lesions, which produced a significant increase in wake and concomitant reduction in NREM and REM sleep. Representative photomicrographs of Nissl-stained brain sections from a (A) VLPOx rat and (B) a sham-L rat. (C) Daily percentages of sleep-wake stages (wake, NREM, REM) in sham-L (white bars) and VLPOx rats (black bars). Bilateral lesions of the VLPO produced a significant increase in wake and concomitant decreases in NREM and REM sleep.

Notes: Values are mean ± standard error of the mean; **P<0.01; scale bar: 500 μm.
Abbreviations: 3V, third ventricle; AC, anterior commissure; MPO, medial preoptic area; NREM, non-REM; OC, optic chiasm; REM, rapid eye movement; sham-L, sham-lesioned; VLPO, ventrolateral preoptic area; VLPOx, VLPO-lesioned.

Figure 2 The wake-promoting effects of armodafinil and methamphetamine are not attenuated in VLPOx rats compared to sham-L rats. Both (A) armodafinil and (B) methamphetamine produced a sustained increase in wake for approximately 3 hours in both VLPOx and sham-L rats. A persisting and significant increase in wake was observed into the (A) 5th hour post-injection hour and the (B) 6th post-injection hour in VLPOx rats compared to sham-L rats. Wake amounts during the 5th and 6th post-injection hours did not differ between armodafinil and methamphetamine injected VLPOx rats and VLPOx rats receiving vehicle injections.

Notes: Data are mean ± standard error of the mean; **P<0.01 compared with VLPOx vehicle group; ^#P<0.01 when compared with either sham-L armodafinil or sham-L methamphetamine group.
Abbreviations: meth, methamphetamine; sham-L, sham-lesioned; VLPOx, ventrolateral preoptic area-lesioned.

Figure 3 c-Fos expression in the dorsal striatum following armodafinil, methamphetamine, or saline injections.

Notes: Intraperitoneal administration of (A) saline did not induce c-Fos expression in the striatum, whereas intraperitoneal administration of (B) armodafinil (200 mg/kg) or (C) methamphetamine (1 mg/kg) induced robust c-Fos expression in the striatum 2 hours post-injection. Scale bar: 200 μm.