RESUMO
Two models of retinal ischemia/reperfusion were developed in an experiment on rats and structural changes in eye tissues in the early and late postischemic periods were studied. Ischemia/reperfusion was modeled by elevation of intraocular pressure to 110 mm Hg for 30 min with air injection into the anterior chamber of the eye with a special device or subconjunctival administration of 0.2 ml 4×10-6 M endothelin-1. Morphological studies of the retina of enucleated eyes were performed in 3, 7, and 30 days after ischemia/reperfusion. In 3 days, signs of retinal ischemia were seen (retinal edema and ganglion cell damage). In the late post-ischemic period (30 days), atrophy of the outer nuclear and outer plexiform layer of the retina was observed in animals with retinal ischemia/reperfusion caused by intraocular pressure elevation and complete destruction of neuronal cells was found after administration of endothelin-1.
Assuntos
Retina/patologia , Doenças Retinianas/patologia , Animais , Apoptose , Modelos Animais de Doenças , Endotelina-1/metabolismo , Pressão Intraocular/fisiologia , Isquemia/metabolismo , Isquemia/patologia , Masculino , Ratos , Ratos Wistar , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Retina/metabolismo , Doenças Retinianas/metabolismoRESUMO
AIM: To study the effect of resveratrol on ocular blood flow in vivo in healthy rats and those that underwent retinal ischemia/reperfusion. MATERIAL AND METHODS: The experimental study was performed on 40 Wistar rats (40 eyes). For ocular blood flow evaluation, color Doppler imaging (CDI), power Doppler (PD), and pulsed-wave spectral Doppler ultrasonography were performed using the Voluson E8 Expert ultrasonic diagnostic system (GE Healthcare). All rats were given resveratrol per os for 2 months of the study. Retinal ischemia/reperfusion injury was induced by a subconjunctival injection of endothelin-1. The control group included 10 intact animals. RESULTS: Signs of ischemic damage of the anterior and posterior eye segments were less pronounced in rats that were given resveratrol during both pre-ischemic (30 days) and post-ischemic (30 days) periods of follow-up. There was also a statistically significant increase in the peak systolic and end diastolic velocity of blood flow as well as a decrease in the resistive index of retrobulbar arteries in those rats that underwent ischemia/reperfusion as compared to the controls. CONCLUSION: Long-term resveratrol use (2 months) has proved effective in improving ocular blood flow in a rat model of retinal ischemia/reperfusion injury.
Assuntos
Olho , Artéria Oftálmica , Traumatismo por Reperfusão , Artéria Retiniana , Estilbenos/farmacologia , Inibidores da Angiogênese/farmacologia , Animais , Antioxidantes/farmacologia , Olho/irrigação sanguínea , Olho/metabolismo , Artéria Oftálmica/efeitos dos fármacos , Artéria Oftálmica/fisiopatologia , Ratos , Ratos Wistar , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fluxo Sanguíneo Regional/fisiologia , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/mortalidade , Traumatismo por Reperfusão/fisiopatologia , Resveratrol , Artéria Retiniana/efeitos dos fármacos , Artéria Retiniana/fisiopatologia , Ribonucleotídeo Redutases/antagonistas & inibidores , Tempo , Resultado do Tratamento , Ultrassonografia Doppler em Cores/métodos , Vasodilatadores/farmacologiaRESUMO
The review presents the most common methods of modeling of retinal ischemia in vitro (chemical ischemia with iodoacetic acid, incubation of the retinal pigment epithelium cells with oligomycin, deprivation of oxygen and glucose) and in vivo (a model with increased intraocular pressure, cerebral artery occlusion, chronic ligation of the carotid arteries, photocoagulation of the retinal vessels, occlusion of the central retinal artery, endothelin-1 administration). Modeling ischemic injury in rats is the most frequently used method in studies, because the blood supply of their eyes is similar to blood flow in the human eyes. Each method has its own advantages and disadvantages. Application of methods depends on the purpose of the experimental study. Currently model of ocular ischemic disease can be obtained easily by injecting vasoconstrictive drug endothelin-1. It is the most widely used method of high intraocular pressure induced ocular ischemic damage similar to glaucoma, occlusion of central retinal artery or ophthalmic artery in human. The development of experimental models of ocular ischemic diseases and detailed investigation of mechanisms of impairment of microcirculation are useful for improve the efficiency of diagnostic and treatment of ischemic diseases of retina and optic nerve.
Assuntos
Olho , Isquemia/complicações , Doenças Retinianas , Animais , Olho/irrigação sanguínea , Olho/metabolismo , Olho/fisiopatologia , Humanos , Metabolismo , Modelos Animais , Modelos Teóricos , Fluxo Sanguíneo Regional , Doenças Retinianas/etiologia , Doenças Retinianas/metabolismo , Doenças Retinianas/fisiopatologiaRESUMO
The review discusses some of the most common methods of ocular microcirculation assessment in animals: fluorescent and indocyanine green angiography, scanning laser ophthalmoscopy with various dyes, laser Doppler flowmetry and velocimetry, color and power Doppler imaging, and pulsed-wave spectral Doppler ultrasonography. Each method possesses certain advantages and disadvantages, thus, the choice between them depends on the purposes and objectives of the given experimental study.
