0bjective To explore the effect of endothelin(ET)、nitrioxide (NO) in plasma on retinopathv in the pregnancy-induced hypertension(PIH)． Methods The 1evel of ET and NO in plasma of 75 cases of in-patient women with PIH and 20 cases of women with the full terms and normal pregnancy before and after delivery was determined by radioimmunoassay．The retinopathy of the patients with FIH before and after delivery was detected by appointed doctor．The levels of ET and N0 in both groups were compared and the relationship between ET and N0 in plasma and the retinopathy before and after the delivery was detected.Results The levels of ET[(145．oo±54.41)ng／L] in serious PIH patients were much higher than that in the control[(81．50±43．80)ng／L]，the minor[(85.30±33.33)ng／L]and middling PIH group[(90．20±39．25)ng／L]．The levels of ET in plasma before and after pregnancy were not changed in PIH patients [(118．70±33．44)ng／L]，but were higher than that in the control group. The levels of plasma NO in serious[(87．56±35．58)ng／L]and middling[(78.11±28.96)ng／L] PIH group were both higher than that in the control group[(46．70±32.64)ng/L]，and the levels in minor(52．56±28．35)ng／L]and middling PIH group were lower than that in the serious PIH group.The level of N0 in plasma of PIH patients after the delivery was much lower than that before the delivery，while higher than that in the control．The positive correlation between levels of ET and NO and retinopathy was found in PIH patients.Conclusions The 1evels of plasma ET and N0 in PIH patients are related to the extent of the disease，and the level of ET in plasma is highly related to the retinopathy in PIH patients, ET and NO might be played an important role in pathogenesis of retinopathy and ET might be a good index in reflecting the rank of retinopathy in PIH.(Chin J Ocul Fundus Dis，2004，20：12-15)
Objective To investigate the changes of ocular hemodynamics in patients with retinal vein occlussion(RVO)． Methods The hemodynamic parameters(PSV,EDV,PI,Vmax)of central retinal artery(CRA)and central retinal vein(CRV)were measured in the involved eyes(n=48) with RVO and the contralateral clinically healthy eyes(n=39) and in the control eyes(n=40) by color Doppler imaging (CDI)(ATLHDI3000). Results Peak systolic velocity (PSV) and end diastolic velocity (EDV) were significantly lower in the CRA of involved eyes and clinically healthy eyes of patients with RVO compared with control eyes,and pulsatility index(PI)was significantly higher in the CRA of involved eyes of patients with RVO compared with control eyes．PSV were significantly lower in the CRA of involved eyes of patients with RVO compared with their clinically healthy eyes．Pulsatility index(PI)was significantly higher in the CRA of involved eyes of patients with RVO compared with their clinically healthy eyes．Maximun vein velocity (Vmax) was significantly lower in the CRV of involved eyes and clinically healthy eyes of patients with RVO compared with control eyes． Conclusion The changes of hemodynamics in CRA,CRV of involved eyes of patients with RVO may invade their clinically healthy eyes．CDI may be helpful to early diagnosis for RVO． (Chin J Ocul Fundus Dis,1998,14:111-113)
OBJECTIVE :To investigate ocular vessel flow velocity in normal eyes by color Doppler imaging(CDI). METHODS: Ninety people (180 normal eyes)had flow velocity measured by CDI in three vessels,ophthalmic artery (OA),central retinal artery(CRA) and posterior ciliary artery (PCA),and the relations between velocity and affecting factors were analysed. RESULT: The diastolic and systolic velocity of OA,CRA and PCA were (31.7plusmn;10.9)cm/s, (7.2plusmn;2.6)cm/,s, (10.2plusmn;3.4)cm/s, (2.8plusmn;1.2)cm/s and (11.3plusmn;3.6)cm/s, (3.2plusmn;1.4)cm/s respectively. The velocity of OA had possitive correl-ativity with RBC,HCT and negative correlativity with age,while it revealed no relationship with sex, laterality of right or left eye,and normal IOP. CDI of ocular vessels in normal eyes is a triangle with three peaks and double sunkens in its frenquency spectum, revealed highly resistant,and both the pulsatility and resistive indexes were relatively high. The width of each frequency band basically was the same,and there was no obvious frequency window. CONCLUSION: The ocular application of CDI might lay the foundation of a comparatively comprehensive knowledge of the ocular hemodynamics. （Chin J Ocul Fundus Dis,1997,13: 99-101）
Objective It has been shown that pigment epitheliumderived factor (PEDF) is an effective anti-apoptosis agent on several kinds of cells of the central nervous system.This study aimed to evaluate the effect of PEDF on pressure induced retinal ischemia in a rat model. Methods Retinal ischemia was induced by increasing the intraocular pressure to 110 mm Hg for 45 minutes via an intracameral catheter.Ten microlit ers (0.1 mu;g/mu;l) PEDF was injected into the vitreous of 4 eyes of each group im mediately after reperfusion and 4 additional eyes received only normal saline as vehicle controls.The animals were euthanized at 2 or 7 days after reperfusion.T he effect of PEDF on retinal degeneration was assessed by measuring the thicknes s of the inner retinal layers (MTIRL) and counting the retinal ganglion cells (R GC) on plastic embedded retinal sections. Results The MTIRL and the RGC counting in eyes treated with intravitreal PEDF were significantly higher than those in vehicle controls (118.1plusmn;5.0) mu;m vs(94.9plusmn;3.0) mu;m (Plt;0.05);(6.0plusmn;1.0) cells/100 mu;m vs (4.5 plusmn;0.5) cells/100 mu;m (Plt;0.05) 7 days after reperfusion,respectively． Conclusion Intravitreal administration of PEDF can ameliorate an ischemiareperfusion retinal injury and may be useful to prevent neuronal degeneration in the inner retina. (Chin J Ocul Fundus Dis, 2001,17:138-140)
Objective To investigate the spatial and temporal regulation effect of VEGF on human fetal retinal vascularization and angiogenesis. Methods The posterior segmental retinas from 54 human fetuses of the 9th week to the 40th week were studied by immunohistodhemistry standing for the expressions of VEGF and PCNA. Results 1. The distribution of VEGF espression was spiking and the peaks were during the 9th-13th and around the 26th week. 2. PCNA immunoreactivity was localized in spindle cells and vascular endothelial cells. The expression level was fluctuated during the developmental process. The peaks were during the 9th-13th and around the 21st week. In these periods, the spindle cells kept proliferating and differentiating, and remodelled subsequently to form the inner side retinal vessels. From the 26th or 34th week, the PCNA immununoreactivity is fully expressed in the vascular endothelial cells of the inner and outer margin of inner nuclear layer(INL) and kept to full terms. 3. Significant positive correlation were shown between the content of VEGF in the retina and that of PCNA in spindle cells and vascular endothelial cells(r=0.736,p＜0.01). Conclusion VEGF was positively involved in modulating human fetal retinal vascularization and angiogenesis. (Chin J Ocul Fundus Dis,1999,15:12-15)
The retinal vessel changes are the primary and major features of retinal vascular diseases. The retinal vessel is part of systemic vessels with its own characteristics to sustain normal retinal function. These basic characteristics are important to the correct understanding and proper treatment of retinal vascular diseases. Always keep in mind that the retinal vessels is one part of the systemic vascular system, thus retinal vascular diseases may have systemic etiology, and systemic drug administration may have a profound effects to the whole body. However retinal vascular system also has its own structural and functional characteristics, thus retinal vascular diseases are also different from the systemic diseases. Finally the main function of retinal vascular network is to maintain the neuro-retinal function, thus we should balance the vision protection and treatments against abnormal retinal blood vessels. Over-treatments may damage the retinal vision.
Objective To study the proximal diameter changes of retinal blood vessel following branch retinal vein occlusion (BRVO). Methods Color fundus photographs and fundus fluorescein angiography (FFA) photographs of 48 patients with typical unilateral BRVO were analyzed using IMAGEnet software. The diameter of retinal artery (RAD) and vein (RVD) close to optic disc (within one DD from the optic disc) in four quadrants including the affected quadrant were measured with linear measuring tools.Results The proximal diameter of RAD and RVD in corresponding normal quadrants of the BRVO eye had no significant change comparing with the contralateral eye. The proximal diameter of RAD, but not RVD of the affected quadrant such as superotemporal （t=-2.342, P=0.026）or inferotemporal （t=-3.069, P=0.010）quadrant, increased remarkably. Conclusions In corresponding affected quadrant with BRVO, only RAD close to optic disc increases markedly, RVD has no significant change.
Objective To observe the changes of tortuosity and bifurcation angle of retinal arteries and veins in each quadrant of the posterior pole in eyes with high myopia.Methods The tortuosity and bifurcation angle of retinal vessels in each quadrant of the posterior pole in 32 patients (52 eyes) with high myopia and 22 healthy people (30 eyes) were observed and compared. The outcomes were analyzed by multivariate analysis of variance. Results The tortuosity of macular vessels and the artery from optic disc in eyes with high myopia was (1.29plusmn;1.10)times;10-4 and (5.39plusmn;1.93)times;10-5 respectively, and in the normal eyes was (4.15plusmn;2.38) times;10-4 and (9.75plusmn;4.99)times;10-5 respectively; there was significant difference between the two groups （t=1.99, 2.00;Plt;0.05）. The bifurcation angle of superior nasal and inferior nasal retinal arteries in eyes with high myopia was（66.17plusmn;14.04）deg; and (61.20plusmn;11.02) deg; respectively, and in the normal eyes was （77.66plusmn;14.12）deg; and (85.86plusmn;16.45) deg; respectively; there was significant difference between the two groups （F=0.77, 0.83; Plt;0.05）. The bifurcation angle of superior temporal and inferior temporal retinal veins in eyes with high myopia was（92.39plusmn;20.36）deg; and (83.56plusmn;23.50) deg; respectively, and in the normal eyes was （79.45plusmn;15.94）deg; and (70.59plusmn;17.27) deg;; there was significant difference between the two groups （F=2.34, 1.83; Plt;0.05）.Conclusions The vessel tortuosity of retinal arteries and the vessels extending from the optic disc to macula is smaller in eyes with high myopia, while the venous tortuosity has no change. The bifurcation angle of retinal arteries in the superior nasal and inferior nasal field was smaller in eyes with high myopia, while the venous tortuosity has no change. The bifurcation angle of retinal veins in the superior temporal and inferior temporal field was larger in eyes with high myopia.
ObjectiveTo observe the stoichiometry of vascular endothelial growth factor receptor 2 (VEGFR2) on the retinal vascular endothelial cell membrane by single-molecule fluorescence imaging.MethodsRhesus monkey retinal vascular endothelial cells (RF/6A) were divided into blank control group (normal culture) and plasmid transfection group [transfected with VEGFR2-green fluorescent protein (GFP) recombinant plasmid]. The expression of GFP in the plasmid transfected group was observed by confocal microscope, and the expression of VEGFR2 in the cells was detected by real-time fluorescent quantitative polymerase chain reaction (qPCR) and Western blot. The fluorescence intensity distribution and bleaching steps of single VEGFR2-GFP molecule on the cell membrane were recorded by single-molecule imaging. The distribution of fluorescence intensity and the number of fluorescence bleaching steps of GFP were recorded.ResultsGFP green fluorescence was observed in the transfected cells 12 hours after transfection. qPCR results showed that the expression of VEGFR2 and GFP mRNA in the plasmid transfected group was significantly higher than that in the blank control group (t=11.240, 12.330; P＜0.001, 0.001). Western blot results showed that the expression of VEGFR2 protein in the plasmid transfected group was significantly higher than that in the blank control group (t=8.346, P＜0.01). The results of single-molecule imaging showed that the fluorescence intensity distribution of VEGFR2-GFP on the surface of RF/6A cell membrane without ligand stimulation was bimodal, in which monomer and dimer were 86.0% and 14.0% respectively. By counting the steps of GFP fluorescence bleaching, the proportions of receptor monomer, dimer, trimer, and tetramer were 81.4%, 12.9%, 5.5%, and 0.3% respectively.ConclusionIn the absence of ligands, VEGFR2 coexists in the form of monomers and dimers on the surface of RF/6A cell membrane, and monomers are dominant.
ObjectiveTo explore the effects of transthyretin (TTR) on biological behavior of retinal microvascular epithelial cell (RMVEC). MethodsRMVEC was cultured in medium with 0 μmol/L and 4 μmol/L TTR. The proliferation, migration and healing abilities (0, 24, 48 hours) of RMVEC with different concentrations of TTR were measured by methyl thiazol tetrazolium (MTT) assay, transwell assay and scarification test. ResultsMTT assay shows that RMVEC with the concentrations of 4 μmol/L TTR [absorbance (A) value=0.17±0.02] glows faster than with the concentrations of 0 μmol/L TTR (A value=0.40±0.03), the difference was statistically significant (t=15.47, P=0.000 1). The transwell assay shows RMVEC with the concentration of 4 μmol/L TTR [(140±7) cells] migrants faster than RMVEC with the concentration of 0 μmol/L TTR [(227±14) cells], the difference was statistically significant (t=5.44, P=0.000 6). The scarification test shows that the RMVEC with the concentration of 4 μmol/L TTR [(134.4±45.4) μm] heals faster than the RMVEC with the concentration of 0 μmol/L TTR [(330.0±23.1) μm], the difference was statistically significant (t=8.25, P<0.01). The cells in 48 hours and 4 μmol/L group were healed completely, but not healed in 0 μmol/L group. ConclusionTTR can promote the proliferation, migration and healing abilities of RMVEC.