Influence of pars plana vitrectomy on ocular surface using noninvasive Keratograph 5M / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To evaluate the influence of pars plana vitrectomy(PPV)on ocular surface using Keratograph 5M. <p>METHODS: Totally 30 consecutive patients(30 eyes)undergoing primary 23G PPV were recruited in the study. Ocular Surface Disease Index(OSDI)questionnaire was performed. Ocular surface parameters, including tear meniscus height(TMH), noninvasive tear break up time(NITBUT)and bulbar redness score were obtained preoperatively, in 2, 4, 8 and 12wk postoperatively by Keratograph 5M. Correlations between all the clinical parameters were analyzed further.<p>RESULTS: The percentages of both photophobia and gritty within 4wk after PPV were significantly higher than preoperation, while they decreased to the preoperative levels in both 8wk and 12wk postoperatively. The percentage of sore eyes in the first week postoperatively was significantly higher than preoperation, but there were no significant differences between the percentages of preoperation and 2, 4, 8 and 12wk postoperatively. OSDI score increased significantly within 4wk postoperatively, but it returned to the preoperative level in 8 and 12wk. TMH increased with 2wk postoperatively, but there were no significant differences compared with preoperation. Both NITBUT-first and NITBUT-average shortened significantly within 8wk postoperatively, but they gradually improved to the preoperative levels in 12wk. Bulbar redness score was significantly higher than the preoperative level within 4wk postoperatively, but it returned to the preoperative level in 8wk. NITBUT-first and NITBUT-average had a significant positive correlation at each visit. TMH had a significant positive correlation with NITBUT-average in the first week postoperatively.<p>CONCLUSION: Keratograph 5M can provide a reliable noninvasive method to assess the influence of PPV on the ocular surface. PPV may cause various changes in both symptoms and signs of ocular surface damages at the early stage, while all these changes will return to preoperative levels gradually in 12wk postoperatively.

Effect of 5-HT7 receptor agonist on pyramidal neurons in the medial frontal cortex in a rat model of Parkinson's disease / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the activity of pyramidal neurons in the medial prefrontal cortex (mPFC) of normal and 6-OHDA-lesioned rats and the responses of the neurons to 5-hydroxytryptamine-7 (5-HT(7)) receptor stimulation.</p><p><b>METHODS</b>The changes in spontaneous firing of the pyramidal neurons in the mPFC in response to 5-HT(7) receptor stimulation were observed by extracellular recording in normal and 6-OHDA-lesioned rats.</p><p><b>RESULTS</b>Both systemic and local administration of 5-HT(7) receptor agonist AS 19 resulted in 3 response patterns (excitation, inhibition and no change) of the pyramidal neurons in the mPFC of normal and 6-OHDA-lesioned rats. In normal rats, the predominant response of the pyramidal neurons to AS 19 stimulation was excitatory, and the inhibitory effect of systemically administered AS 19 was reversed by GABAA receptor antagonist picrotoxinin. In the lesioned rats, systemic administration of AS 19 also increased the mean firing rate of the pyramidal neurons, but the cumulative dose for producing excitation was higher than that in normal rats. Systemic administration of AS 19 produced an inhibitory effect in the lesioned rats, which was partially reversed by picrotoxinin. Local administration of AS 19 at the same dose did not change the ?ring rate of the neurons in the lesioned rats.</p><p><b>CONCLUSION</b>The activity of mPFC pyramidal neurons is directly or indirectly regulated by 5-HT7 receptor, and degeneration of the nigrostriatal pathway leads to decreased response of these neurons to AS 19.</p>

Effect of sodium nitrite on phosphorylation of cytoskeletal proteins and spatial learning and memory in rats / 生理学报

The present study was aimed to explore the effect of sodium nitrite on cytoskeletal protein phosphorylation and spatial learning and memory in rats. Rats were served with drinking water containing sodium nitrite (100 mg/kg) for 60 days, then, the ability of spatial learning and memory of the rats was measured by Morris water maze. Phosphorylation level of tau and neurofilament, and the expression of protein phosphatase 2A (PP2A) catalytic subunit in the hippocampus were detected by immunohistochemistry and Western blot. In comparison with the rats served with normal tap water, the rats served with sodium nitrite water showed significantly longer latency to find the hidden platform in Morris water maze (P < 0.05), elevated phosphorylation level of tau and neurofilament, and decreased expression of PP2A catalytic subunit (P < 0.05). These results indicated that administration of sodium nitrite could impair the spatial learning and memory of the rats, and the hyperphosphorylation of cytoskeletal proteins and the down-regulation of PP2A might be underlying mechanisms for the impairment.

Intraventricular injection of 5,7-dihydroxytryptamine alters neuronal activity of neurons in the medial prefrontal cortex of rat / 生理学报

The present study is aimed to investigated the firing activity of pyramidal neurons and interneurons in the medial prefrontal cortex (mPFC) in rats with bilateral intraventricular injection of 5,7-dihydroxytryptamine (5,7-DHT) by using in vivo extracellular recording. The results showed that the injection of 5,7-DHT reduced the 5-hydroxytryptamine (5-HT) levels in the mPFC and dorsal raphe nucleus in the rats. The firing rate of mPFC pyramidal neurons in rats with 5,7-DHT injection was significantly higher than that of normal rats, and the firing pattern of these neurons also changed significantly towards a more burst-firing, while the injection decreased the firing rate of mPFC interneurons and changed the firing pattern of the interneurons towards a more irregular. These results indicate that the lesions of the serotonergic neurons lead to the changes in the firing activity of mPFC pyramidal neurons and interneurons, suggesting that serotonergic system plays an important role in the regulation of the neuronal activity in the mPFC.