Chronic intraventricular infusion with NGF improves LTP in old cognitively-impaired rats

Aged (21 months) cognitively-impaired male Sprague Duwley rats received intraventricular infusion of nerve growth factor (NGF) or cytochrome C (Cit C) for 14 or 28 days using miniosmotic pumps and were evaluated either 1 week or 3 months after treatment. Groups of untreated young, aged-impaired and aged non-impaired rats were also evaluated. Under narcose recording and stimulating electrodes were stereotactically implanted in the dentate gyrus and the perforant path. The stimulation intensity was individually adjusted to obtain a half-maximal population spike (P) for test stimuli and a quarter-maximal for tetanization. The amplitude and latency of P and the slope (S) of the field EPSP were determinated before and at 2, 5, 15, 30 and 60 min after tetanization at 400 Hz. Paired stimuli at 30 ms inerval were also applied before and afeter tetanization. Aged, cognitively impaired rats showed an absent S potentiation and a delayed P potentiation, both in amplitude and latency, while non-impaired rats behaved like the young controls. Paired pulse inhibition showed no difference among groups before or after tetanization suggesting that the impaired potentiation is not due to an increased retroactive inhibition. NGF treatment ameliorates LTP deficits to levels equivalent to non-impaired rats, while Cit C controls showed no improvement. No differences appear among NGF treated groups, but evidence suggest that the animals evaluated 3 months after treatment developed a stronger potentiation

Patrón de actividad motora espontánea en babuinos sagrados viejos / Spontaneous motor activity pattern in old sacred papio

Se expresa que los primates no humanos han sido estudiados extensivamente en relación con el patrón social y sexual, sin embargo, los mecanismos a través de los cuales la ontogenia ejerce su influencia sobre el uso de habitats, la locomoción y la adaptabilidad estructural permanecen aún sin resolver. Señala el interés en desarrollar modelos animales neurogerontológicos, para lo cual se desarrolla una base de datos en relación con la actividad motora espontánea, procesos congnoscitivos, estudios imagenológicos computarizados de cerebro, etc. para evaluar en primera instancia la sensibilidad de estos fenómenos funcionales al paso de la edad en babuinos y macacos