Expression of dopamine transporter in the different cerebral regions of methamphetamine-dependent rats.

OBJECTIVES: To observe the expression of the dopamine transporter (DAT) in six cerebral regions of a methamphetamine (MA)-dependent rat, which were frontal cortex, nucleus accumbens septi, striatum, hippocampus, substantia nigra and ventral tegmental area. METHODS: The rats were administrated intraperitoneally with 10 mg/kg/day of MA for 10 days consecutively; the behaviour changes were measured via the conditioned place preference (CPP), and the scores of stereotyped behaviour (SB) were used to confirm animal addiction. Then, the animals were further injected with MA respectively for 1, 2, 4 and 8 weeks to establish different periods of MA-dependent models. The expressions of DAT and DAT messenger RNA in six cerebral regions were detected. RESULTS: The results of CPP and SB scores were significant different when comparing all four experimental groups with the control group (p < 0.05). Comparing between different experimental groups, the expression of DAT mainly decreased and had dynamic changes in the same regions (p < 0.05). Comparing the different regions with each other in the same experimental group, the expression of DAT also had significant difference in several regions p < 0.05). CONCLUSIONS: The expression of DAT mainly decreased and had different in the six cerebral regions at the same MA-dependent time period as well as at different time periods in the same cerebral region. It was speculated that DAT might play a crucial role in the mechanism of MA dependence.

Trypan blue- and indocyanine green-assisted epiretinal membrane surgery: clinical and histopathological studies.

PURPOSE: To evaluate the clinical outcome and electron microscopic findings of trypan blue (Tb) and indocyanine green (ICG) assisted epiretinal membrane (ERM) surgery. METHODS: This is a prospective consecutive noncomparative interventional case series. After pars plana vitrectomy, 0.1 ml of 0.6 mg/ml Tb solution was applied for 1 min under air for ERM staining. After ERM removal, internal limiting membrane (ILM) was further peeled after staining with 0.2 ml of 1 mg/ml ICG solution. Intraoperative specimens were sent for electron microscopy. Tb was considered useful if the edge of ERM was stained where peeling could be initiated with a clearer visualisation of the overall extent of the ERM. RESULTS: In all, 16 eyes from 16 patients were recruited. There were nine grade 1 ERMs, five grade 2 ERMs, and two grade 3 ERMs. Tb was useful in six (67%) of the nine eyes with grade 1 ERMs and in all eyes with grade 2 or 3 ERMs. The three remaining grade 1 ERMs were removed together with surrounding ILM that was stained by ICG. The mean line of improvement was 1.3 lines with the median BCVA improved from 6/12 to 6/9. All 16 eyes had symptomatic improvement and none developed ERM recurrence. No complication related to Tb or ICG was observed clinically or angiographically. Electron microscopy of the Tb-stained ERM specimens showed fragments of ILM in all specimens. CONCLUSIONS: Tb and ICG are useful intraoperatively to improve the visualisation and facilitate complete removal of ERM and ILM in macular ERM surgery.