The activities and distributions of succinate dehydrogenase(SDH),malic dehydrogenase(MDH),lactic dehydrogenase(LDH),acid phosphatase(ACP) and alkaline phosphatase(AKP) in retinal vessels were studied and observed with enzymatic histochemical techniques. The retinal vessels showed a b LDH activity, moderate SDH and MDH activity. The dehydrogenase activity described above was evenly and equally distributed in the microvasculature between arterioles and venules, and was the best in arteries. AKP showed predominant activity in the endothelial cells of capillaries and arterioles which were stained bly. No activity for ACP observed in the retinal vessels. The observations above indicate that the retinal vessels are metabolically active and have a great capacity for glycolysis. （Chin J Ocul Fundus Dis,1992,8:6-9）
The abnormalities of retinal vessels such as retinal arteriolar narrowing, arteriovenous nicking, micro-aneurysms, retinal hemorrhages, and cotton wool spot are closely related to systemic diseases including hypertension, diabetes mellitus, cardiovascular disorders, stroke and renal diseases. The modern retinal vessels examination technology has features of quick noninvasive, quantitative standardized and intelligent analysis. Taking advantage of these to fully discover the retinal vascular abnormalities and get deeper understanding of the relationship between its' mechanism and systemic vascular diseases is not only helpful to better diagnose and treat retinal vascular diseases, but also contributes to predicting the risk and prognosis of systemic diseases. We suggest emphasizing on the study of correlation between retinal vascular abnormalities and systemic vascular diseases using modern retinal vessels examination technology. It will provide the preventive clue of diseases of circulatory system by finding out the retinopathy. Meanwhile, correctly treating systemic diseases would get a better prognosis of the retinopathy. They exist side by side and play a part together for providing a better prognosis, which would be a new direction for the doctors and scientists in the new era.
Objective To investigate the effect of hypoxia on the exp ression and function of integrin receptor αvβ3 of bovine retinal vascular endotheliocytes. Methods Bovine retinal vascular endotheliocy tes in the culture dishes coated by vitronectin was put into the normal and hypoxemic condition, respectively. Enzyme linked immunosorbent assay and cell adhesion analysis were used to detect the expression and function of integrin receptor αvβ3 in bovine retinal vascular endotheliocytes, respectively. Results Under the condition of hypoxia, the expression of αvβ3 increased gradually, and reached the peak at the 48th hour. The expression of αvβ3 at the 60th and 72nd hour in hypoxia group was higher than that in the normal group. Bovine retinal vascular endotheliocytes absorbed more Vn of extra-cellular matrixes (ECM) after cultured under hypoxemic condition for 24 hours.Conclusion Hypoxia may up-regulate the expression of αvβ3, which promote the adsorbability of endotheliocytes.(Chin J Ocul Fundus Dis，2004，20：360-363)
ObjectiveTo explore the effect of estrogen on the permeability of retinal blood vessel by ovariectomy.MethodsTwenty-two healthy rats were divided into experimental and control group randomly. Estrogen level of rats decreased due to ovariectomy in the experimental group while stabilized by sham-ovariectomy in the control group. The results were confirmed by vaginal epithelium smearing. Retinal vein occlusion was established by photodynamic method, and leakage of Evan's blue in retina was determined by spectrophotometer.ResultsMature value of vaginal epithelium decreased significantly in ovariectomy rats（t=21.008，P=0.000） while not significantly in sham-ovariectomy ones （t=0.319，P=0.756）; the mean leakage of Evans blue was (25.503 0±4.378 47) ng/mg in experimental group, and (17.830 0±4.265 69) ng/mg in the control group, and the difference between the two groups is significant（t=3.969 36，P=0.001）.ConclusionOvariectomy is an useful method to study the effect of estrogen on ocular diseases, and when estrogen level decreases, the permeability of retinal blood vessel increases.(Chin J Ocul Fundus Dis, 2005,21:174-176)
ObjectiveTo evaluate the protective effect of estrogen on survival of retinal ganglion cells (RGCs) after transient retinal ischemia-reperfusion (RIR) in rats.MethodsRIR was induced in 60 ovariectomized adult rats (OVX) by increasing intraocular pressure via an intracameral catheter. All of the rats were divided into two groups randomly: in experimental group, the rats underwent a subcutaneous injection with 17β-estrodiol（100 μg/kg） 2 hours before retinal ischemia; and in the control group, saline water was injected correspondingly. The number of RGCs and the thickness of the inner retinal layers were mesured by HE staining method before and 12, 24, 48, and 72 hours after reperfusion. TdT-mediated biotin-dUTP nick end labelling (TUNEL) staining technique was used to examine the apoptosis of RGCs.ResultsTwenty-four and 48 hours after reperfusion, the number of apoptotic cells in experimental group was obvious lower than that in the control group(Plt;0.05), and the number of RGCs in experimental group was higher than that in the control group(Plt;0.05).ConclusionEstrogen can protect retinal neurons from transient RIR in ovariectomized rats.(Chin J Ocul Fundus Dis, 2005,21:177-179)
Objective To evaluate the correlation of oxygen saturation of retinal vessels and diabetic retinopathy (DR) stages or HbA1c level in patients with DR. Methods Cross sectional study. A total of 102 patients (102 eyes) with DR and 20 age-matched healthy controls (20 eyes) (normal control group) were enrolled in this study. DR patients were divided into mild and moderate non-proliferative DR (NPDR) group (55 patients), severe NPDR group (26 patients) and proliferative DR (PDR) group (21 patients). DR patients were also divided into 3 groups according to the HbA1c level including HbA1c＞9% (8 patients), HbA1c 7% – 9% (33 patients) and HbA1c＜7% group (61 patients). The oxygen saturation of retinal vessel was measured by spectrophotometric oximetry unit in the retinal vessels with a diameter greater than 60 μm in the area around the optic disc. Results The retinal artery oxygen saturation of patients in severe NPDR group was significantly higher than that in mild to moderate NPDR group and normal control group (F=13.670,P＜0.05). The retinal vein oxygen saturation of patients in PDR group was significantly higher than that in mild to moderate NPDR group and normal control group (F=6.379,P＜0.05). The difference between retinal artery and vein oxygen saturation of patients in severe NPDR group was significantly bigger than that in mild to moderate NPDR group and PDR group (F=5.536,P＜0.05). The retinal artery and vein oxygen saturation in patients of HbA1c＞9% group were significantly higher than that in HbA1c 7% – 9% group and HbA1c＜7% group (F=9.989, 10.208;P＜0.05). The differences between retinal artery and vein oxygen saturation were same between patients in HbA1c＞9%, HbA1c 7%＜9% and HbA1c＜7% group (F=1.836,P＞0.05). Conclusions The retinal artery and vein oxygen saturation in DR patients are related to the DR stages. Severe NPDR patients show the highest retinal artery oxygen saturation as well as biggest difference between retinal artery and vein oxygen saturation. There is also a trend that retinal vein oxygen saturation increases with higher DR stages. In addition, there is a positive correlation between the levels of HbA1c and retinal vessel oxygen saturation.
ObjectiveTo investigate the relationship between retinal vessel diameters and cerebral infarction of carotid artery stenosis patients. MethodsEighty-seven patients (174 eyes) with carotid stenosis were included in this study. There were 49 males and 38 females, with an average age of (65.25±7.85) years. Thirty-four patients were suffered from cerebral infarction (cerebral infarction group), and the other 53 patients had no cerebral infarction (control group). There was no significant difference in age (t=1.916), male rate (χ2=0.142) and carotid stenosis extent (χ2=0.785) between the two groups (P=0.059, 0.706, 0.675). All patients underwent color fundus photography after mydriasis. Retinal vascular caliber measurements were performed using IVAN software. The main parameters were central retinal artery diameter (central retinal artery equivalent, CRAE), the diameter of the central retinal vein (central retinal vein equivalent, CRVE) and the retinal arteriole to venular ratio (AVR). The relationship between retinal vessel diameter and cerebral vascular disease were analyzed with logistic regression analysis. ResultsIn cerebral infarction group, CRVE, CRAE and AVR ratios were (132.90±20.67) μm, (243.47±43.92) μm and 0.56±0.10, while the control group was (145.26±21.59) μm, (224.99±32.35) μm and 0.68±0.13 respectively. There were significant differences between the two groups (t=-2.648, 2.257, -4.631; P < 0.05). After correction for risk factors, such as age, smoking history, CRAE reduction and CRVE increases were significantly correlated with cerebral infarction. ConclusionCRAE reduction and CRVE increases are risk factors of cerebral infarction in patients with carotid stenosis, and it is useful in the prediction.
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)
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 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.