RESUMEN
Objective To investigate the correlation between cognitive development and levels of dopamine(DA) and 3,4-dihydroxyphenylacetic acid(DOPAC)in the hippocampus of 80-day-old neonatal rats born of fear-impaired pregnant rats. Methods The pregnant rat model of fear-impaired kidney was established by watching other rats shocked with electricity. The cognitive development of the neonatal rats was assessed by Morris water maze test at 80 days after birth. The brain microdialysis samples of the right hippocampus were collected using a stereotaxic instrument, and the levels of DA and DOPAC were determined by HPLC-ECD. Results Compared with the control group, the mean escape latency of the 80-day-old neonatal rats in the model group was increased. Their swimming speed was slower. The 20% time spent in the peripheral zone became longer, and the frequency of platform crossing was decreased, showing significant differences(P< 0.05). The levels of DA and DOPAC in the extracellular fluid of the hippocampus of the 80-day-old neonatal rats in the model group were decreased at each time points of perfusion, showing a significant difference(P <0.05). The level of DA, a kind of monoamine neurotransmitter in the hippocampus, was positively correlated with the mean escape latency,the frequency of passing the platform of the 80-day-old rats,while was negatively correlated with the 20% time spent in the peripheral zone, with a significant correlation(P < 0.05). In addition, there was a positive correlation between the DOPAC level and the mean escape latency, the frequency of passing the platform(P< 0.05). Conclusions Fear-impaired pregnant rats can affect the spatial learning and memory ability of their 80-day-old neonatal rats,with reduction in the levels of DA and DOPAC in the hippocampus, which is closely correlated with the cognitive development of the neonatal rats.
RESUMEN
<p><b>OBJECTIVE</b>To study the effects and the therapeutic mechanism of hyperbaric oxygen (HBO) on prostaglandin E(2) (PGE(2)) in alveolar bone and gingiva of experimental periodontitis in animal.</p><p><b>METHODS</b>Experimental periodontitis was produced by silk thread sutures combined with high content sugar diet. For HBO therapy, they were exposed to a pressure of 0.25 MPa (2.5ATA), breathing pure oxygen one session a day for 60 min. The treatment course was 2 weeks. The value of PGE(2) in gingiva and alveolar bone was analyzed by enzyme immunoassay (EIA).</p><p><b>RESULTS</b>The value of PGE(2) in gingiva of control group was 3.21 ng/g, and that of PGE(2) in alveolar bone was 3.22 ng/g. The contents of PGE(2) in gingiva (13.96 ng/g) and alveolar bone (13.32 ng/g) of periodontitis group increased markedly than control group (P < 0.01). The contents of PGE(2) in gingiva (5.21 ng/g) of HBO group were 62.7% which was lower than that of periodontitis group, and the value of PGE(2) in alveolar bone (4.05 ng/g) were 69.6% lower than that of periodontitis group. The difference of PGE(2) in gingiva or alveolar bone was significant for the HBO group and periodontitis group (P < 0.01).</p><p><b>CONCLUSIONS</b>The contents of PGE(2) in alveolar bone and gingiva increased markedly when experimental periodontitis has formed. The value of PGE(2) in alveolar bone and gingiva reduce markedly after HBO exposure, and the decreased rate of PGE(2) in alveolar bone is more evident than that of PGE(2) in gingiva after HBO therapy.</p>