CGS 5649 B, a new compound, reverses age-related cognitive dysfunctions in rats

Effects of Post-Training Blockade of GABA<sub>B</sub> Receptor on Memory of Food Location and Expression of Synapsin I in the Hippocampus of Pigeons (<i>Columba livia</i>)

“…Our study agrees with previous studies showing spatial learning in food location tasks by pigeons [19] [20] [22] and by Zebra finches [2] [23]. Furthermore, our data showing the enhancing effect of GABA B blockade on the performance in food location task confirm, for pigeons, the literature on enhancement of behavioral and cognitive processes after the use of GABA B receptor antagonist in mammals [10]- [12] [27] [28]. In addition, the behavioral data suggest that the blockade of GABA B receptors interfered both with processes of consolidation and with the persistence of the food location memory.…”

“…ANOVA showed a significant effect of group (F 2, 15 = 16.93; p < 0.001), which was related with the higher accuracy of choice in PHACR than in SALR and NTRR groups in both the final training and the test (p < 0.05). pigeon's brain [10], and (right), a digital image of the hippocampus with indication of the dorsal (DHp) and ventral (VHp) regions of the hippocampus, which were used for the cell counting analysis. Panel (b) presents digitized images of Synapsin I-positive cells, which were obtained from frontal, unilateral images of the dorsal region of the hippocampus sections around the level AP 6.75 [10], for birds of the groups PHAC, SAL, NTR, with the immunohistochemical analysis conducted after the 7 th session of training and in the PHACR, SALR and NTRR groups, with the analysis conducted after the test.…”

“…pigeon's brain [10], and (right), a digital image of the hippocampus with indication of the dorsal (DHp) and ventral (VHp) regions of the hippocampus, which were used for the cell counting analysis. Panel (b) presents digitized images of Synapsin I-positive cells, which were obtained from frontal, unilateral images of the dorsal region of the hippocampus sections around the level AP 6.75 [10], for birds of the groups PHAC, SAL, NTR, with the immunohistochemical analysis conducted after the 7 th session of training and in the PHACR, SALR and NTRR groups, with the analysis conducted after the test. The immunoreactivity for Synapsin I, characterized by marking of the neuronal cytoskeleton, was more intense in the PHAC and PHACR groups than in the other groups.…”

“…Numerous studies show the effects of GABA A receptor in learning [9], but the role of GABA B receptor in hippocampus-dependent memory processes, particularly in birds, still needs research. Administration of GABA B receptor antagonists has been linked to increased spatial memory in rodents [10]- [12] and humans [13]. GABA B receptor antagonists have also been reported to induce up-regulation of Synapsin I expression-one molecule associated with neuroplasticity underlying hippocampus-dependent spatial memory [14] [15].…”

Effects of Aging on Inhibitory Learning and Short-Term Memory in <em>Drosophila Melanogaster</em>

“…Literature in rodents as well gives evidence of an age-linked impairment of central inhibitory abilities. Indeed, some studies in mice or rats have shown the increased difficulties of old animals to learn a passive avoidance task (Lamberty and Gower, 1990;Fagioli et al, 1992;Mondadori et al, 1992). To try to understand our present results, we then hypothesized of a greater susceptibility in old flies to peripheral mechanisms (sensory adaptation to sucrose, motor fatigue) which might have increased their suppression performances.…”