RESUMEN
Long-term potentiation (LTP) is considered a cellular correlate of memory processing. A short-lasting early-LTP can be prolonged into a late-L TP (>4h) by stimulation of the basolateral amygdala (BLA) or motivational behavioral stimuli in young, but not in aged, cognitively impaired rats. We measured the changes in transmitter release-induced by BLA or behavioral reinforcement-in young and aged cognitively impaired rats, after implanting a microdialysis cannula at the dentate gyrus. Samples were taken under baseline conditions and during stimulation of BLA. Rats were water deprived and tested again next day, taking samples after allowing access to water. Higher concentrations of choline, HIAA, aspartate, glutamate, and glycine were found in baseline samples from young animals compared to aged. In young animals, BLA stimulation increased the levels of ACh and reduced norepinephrine and serotonine, while behavioral reinforcement reduced the levels of glutamate and glycine. These effects were absent among aged rats, suggesting that this reduced neurochemical response might be linked to the impaired LTP-reinforcement reported previously.
Asunto(s)
Envejecimiento/fisiología , Giro Dentado/metabolismo , Potenciación a Largo Plazo/fisiología , Neurotransmisores/metabolismo , Acetilcolina/metabolismo , Animales , Ácido Aspártico/metabolismo , Colina/metabolismo , Ácido Glutámico/metabolismo , Glicina/metabolismo , Ácido Hidroxiindolacético/análisis , Microdiálisis , Norepinefrina/metabolismo , Ratas , Ratas Sprague-Dawley , Serotonina/metabolismo , Transmisión Sináptica/fisiologíaRESUMEN
The effects of vaginocervical stimulation (VCS) on glutamate (GLU), aspartate (ASP), gamma-aminobutyric acid (GABA), noradrenaline (NA), arginine (ARG) and nitric oxide (NO) (citrulline) release in the nucleus of the solitary tract (nTS) were measured in anaesthetised female rats as a function of the oestrus cycle. During pro-oestrus/oestrus (P/E), but not during met-oestrus/di-oestrus (M/D), VCS significantly increased concentrations of NA, ASP, GLU, NO (citrulline) and GABA, but not ARG. Basal NA concentrations were also increased in P/E. These effects were prevented by bilateral section of either the vagus nerve or pelvic and hypogastric nerves. Vagotomy also significantly decreased basal NO concentrations in M/D and P/E while pelvic and hypogastric nerve section significantly increased GABA concentrations. Our results therefore confirm that the nTS is a relay structure for the visceral afferents sending information from the uterus into the central nervous system. The ability of VCS to trigger classical transmitter release and NO in the female is influenced by the stage of the oestrous cycle and is routed both via the vagus and pelvic/hypogastric nerves.
Asunto(s)
Estro/fisiología , Genitales Femeninos/inervación , Neuronas/metabolismo , Neurotransmisores/metabolismo , Óxido Nítrico/metabolismo , Núcleo Solitario/metabolismo , Aferentes Viscerales/fisiología , Animales , Arginina/metabolismo , Ácido Aspártico/metabolismo , Cuello del Útero/inervación , Cuello del Útero/fisiología , Desnervación/efectos adversos , Femenino , Genitales Femeninos/fisiología , Ácido Glutámico/metabolismo , Plexo Hipogástrico/fisiología , Plexo Hipogástrico/cirugía , Microdiálisis , Neuronas/citología , Norepinefrina/metabolismo , Estimulación Física , Ratas , Ratas Wistar , Núcleo Solitario/citología , Vagina/inervación , Vagina/fisiología , Nervio Vago/fisiología , Nervio Vago/cirugía , Aferentes Viscerales/citología , Ácido gamma-Aminobutírico/metabolismoRESUMEN
Cytokine production of unstimulated and mitogen-stimulated peripheral blood mononuclear cells of 31 children vertically infected with human immunodeficiency virus type 1 (HIV) and with different patterns of disease progression was evaluated to establish possible correlations between the immunologic and the clinical findings. Production of interferon gamma and interleukin-2 (type 1 cytokines), and of interleukin-4 and interleukin-10 (type 2 cytokines), was analyzed in seven symptom-free patients (Centers for Disease Control and Prevention class P-1B), 10 patients with mild symptoms (class P-2A), and 14 patients with severe symptoms (class P-2B-F). Cytokine production was compared with that of 10 age- and sex-matched control subjects who were seronegative for HIV. The HIV-infected patients produced significantly fewer type 1 cytokines and significantly more type 2 cytokines than the uninfected control subjects. No differences in the production of interferon gamma and interleukin-2 were detected among the different clinical categories of HIV-infected patients. In contrast, interleukin-4 production was augmented in the patients with class P-2A (p < 0.05) and class P-2B-F HIV infection (p < 0.03), in comparison with the children with class P-1B infection. The increase in interleukin-4 production was paralleled by an increase in the number of children with hyperimmunoglobulinemia E in each of the clinical groups (0% in class P-1B; 40% in class P-2A; and 71% in class P-2 B-F infection). Similarly, interleukin-10 production was increased both in patients with class P-2A and in those with class P-2B-F infection, in comparison with the children with class P-1B disease (p < 0.006 and < 0.04, respectively). These data indicate (1) that vertically acquired HIV infection results in decreased production of type 1 cytokines and in increased production of type 2 cytokines, and (2) that an increased production of type 2 cytokines correlates with hyperimmunoglobulinemia E and is present in, and may be characteristic of, the symptomatic phases of childhood HIV infection.