The formula C12H14N4O13 was determined by HRESIMS (m/z 423.0631 as [M + H]+; calcd. 422.0508). The ESI-MS/MS spectrum in the positive mode for nigriventrine revealed main fragment ions with m/z 405.0052, 388.9932, 361.0143, 349.0632, 317.0211, 299.9906, 248.0321, 233.9894, 189.0235, 172.9785, 130.8851, 102.8918, and 75.0012 as [M + H]+ ( Fig. 4A). The pattern of fragmentation revealed that the ions of m/z 349.0632, 361.0143, 388.9932

and 405.0052 resulted from the fragmentation of the intact compound, whereas the ions of m/z 75.0012, 102.8918, 130.8851, 172.9785, 189.0235, selleck products 233.9894, 248.0321, 299.9906 and 317.0211 resulted from the fragmentation of the molecule that lost two oxygens from one of the piperidinyl moieties [M + H – 32] (m/z 370.0631), as represented in Fig. 4B. The pattern of fragmentation proposed in Fig. 4B fitted well with the chemical structure proposed for nigriventrine in Fig. 3A and corroborated the structure proposed by NMR analysis. Nigriventrine was ICV administered to male Wistar rats, and the c-Fos-immunoreactive (ir) neurons were counted in all active brain regions. Examination GSK126 chemical structure of the four coronal sections sliced from the rat brains revealed that seven brain regions expressed the c-Fos protein; therefore, the Fos-ir neurons of all these regions were mapped (Fig. 5 and Fig. 6) and counted (Fig. 7). Comparing the counting of nigriventrine-treated and saline-treated neurons

revealed that the brain areas stimulated by nigriventrine were the motor cortex, sensory cortex, piriform cortex, median preoptic nucleus, dorsal endopiriform nucleus, lateral septal nucleus and hippocampus. The counting

of Fos-ir neurons in these regions indicated that the stimulation of the piriform cortex was particularly high compared to the other regions (Fig. 5E and F; Fig. 7). The widespread activation of c-Fos by nigriventrine in different populations Buspirone HCl of neurons of rat brain could be due to secondary actions resulting from the activation of specific brain regions because of the connectivity and network structure between spatially distributed brain areas. This finding has been previously reported for the spatiotemporal spreading of Fos induction by different types of stimuli (McIntosh et al., 2003 and Tchelingerian et al., 1997). Different brain regions present different propensities for generating epileptiform activity in the presence of convulsant stimuli. The piriform cortex and the hippocampus have strong tendencies to generate epileptiform events. Specifically, the piriform cortex has a propensity to generate spontaneous interictal spikes, which in turn may result in epileptic events (Namvar et al., 2008 and Rigas and Castro-Alamancos, 2004). It is interesting to note that the piriform cortex was the most intensely labelled region of c-Fos expression in the rat brain after treatment with nigriventrine (Fig. 7).