Color doppler imaging and plasma levels of endothelin‐1 in low‐tension glaucoma

Abstract

Direct immunofluorescence, on the other hand, was done to show up the MAC leucocytary a n t i g e n h r the evaluation of the esterasic non-specific activity of the monocytes, a direct immunofluorescence was performed on histological sections of the Matrigel cleaned of paraffin with trypsin 0.1%.The sensitivity of this experimental model of angiogenesis in vivo was evaluated in preliminary experiments by adding to the Matrigel known quantities of angiogenetic factors of proteic (bFGF, TNF, VEGF) and lipidic (PAF) natures. The results were expressed as percentage * SME of the vascular area with respect to the total Matrigel by means of one-way ANOVA Dunnet's test.Aqueous humour was obtained from 5 patients (2 male and 3 female) who were diabetic, of whom 2 were affected by quiescent retinopathy and from 5 patient$ all male, with neovascular glaucoma. In addition, as control group, the aqueous humour of 6 patients (3 male and 3 female) with senile cataract was studied. The three groups of patients did not differ significantly as to mean age: 67*7,61*4 and 74*6 respectively. Results and discussionThe aqueous humour of diabetic patients with or without retinopathy proved to possess in vivo a powerful angiogenetic activity which causes intense neoformation of vascular structures characterized by an evident lumen A similar angiogenetic activity was observed when the Matrigel was incubated with the aqueous humour of patients affected by neovascular glaucoma ( fig. 1 - panel B).The area occupied by the newly-formed vessels with respect to the total of Matrigel was 72*7%0 and 34+15%0 respectively ( fig. 2).On the contrary, the aqueous obtained from patients affected by senile cataract did not show in vivo any significant angiogenetic response ( fig. 1 -panel D). ConclusionsThis work demonstrates for the first time in an in vivo model of angiogenesis that the aqueous humour of patients affected by diabetic retinopathy and neovascular glaucoma can induce a ma- Color doppler imaging and plasma levels of endothelin-1 in low-tension glaucomaEye Clinic, University of Bologna, Bologna AbstractEndothelin-1 (ET-1) is a potent vasoconstrictor peptide produced by vascular endothelin cellsThere are reports in the literature that ET-1 plasma levels are raised in low tension glaucoma (LTG On the basis of our experience, we think that GON and the visual field damage found in LTG can be attributed to an alteration in the endothelial selfregulating sections and consequent vascular insufficiency, particularly pronounced in the posterior ciliary arteries which, since it is these that provide the blood supply to the optic nerve head, leads to irreversible functional damage.

A virtual-system coupled multicanonical molecular dynamics simulation: Principles and applications to free-energy landscape of protein–protein interaction with an all-atom model in explicit solvent

“…ET1, which is a potent and long-lasting vasoconstrictor on smooth muscles of a vessel, [28][29][30][31] is thought to be an important drug target because it is related to many human diseases. [32][33][34][35][36] Because of its two intra-peptide disulfide bonds, ET1 has a compact tertiary structure in solution. In both the NMR [37][38][39] and X-ray 40 structures, the N-terminal region of ET1 adopts a somewhat distorted strand and the middle region forms a helix.…”

Black Currant Anthocyanins Normalized Abnormal Levels of Serum Concentrations of Endothelin-1 in Patients with Glaucoma

“…3,4 This is because, in addition to the elevated IOPs, ocular blood circulation, oxidative stress, and other mechanisms are also believed to be involved in the GON etiology. Regarding ocular blood circulation, evidence from numerous reports indicating that insufficient retinal and optic disc blood supply are involved in the GON etiology includes the following: (1) Disc hemorrhages frequently exist in patients with open-angle glaucoma (OAG) [6][7][8] ; (2) retinal vascular diseases, such as retinal vein occlusion, are frequently associated with OAG patients with OAG 10,11 ; (4) there are abnormal levels of the concentration of plasma endothelin-1 (ET-1) in patients with OAG as compared with healthy control subjects [12][13][14][15] ; (5) platelet aggregation ability is remarkably increased in patients with OAG compared with that in normal subjects. 16 As for oxidative stress, reactive oxygen species (ROS) are produced as a consequence of normal aerobic metabolism.…”

Involvement of Endothelin-1 in the Pathophysiology of Normal-Tension Glaucoma

“…We and Cellini et al found that plasma ET-1 levels were significantly higher in patients with NTG without systemic vascular or circulatory disorders than in normal controls [11,13] . We also demonstrated higher plasma ET-1 levels in NTG patients at the initial stage of visual field loss than in those at the middle stage [11] .…”

“…A few research groups, including our own, have reported that plasma ET-1 levels may be associated with the pathogenesis of glaucoma, particularly normal-tension glaucoma (NTG) [11][12][13][14] . We and Cellini et al found that plasma ET-1 levels were significantly higher in patients with NTG without systemic vascular or circulatory disorders than in normal controls [11,13] .…”

“…Kaiser et al found no physiological increase in ET-1 plasma levels in NTG patients after changing from the supine to upright position, suggesting that vascular dysfunction may be involved in the pathogenesis of optic nerve damage in NTG [12] . A study using color Doppler imaging revealed vascular insufficiency in NTG patients, particularly in the posterior ciliary arteries that provide the blood supply to the optic nerve head (ONH) [13] . Another study indicated that resistivity index in the ophthalmic arteries was positively related to plasma ET-1 levels [14] .…”