Secretoneurin in the peripheral ocular innervation

PURPOSE: To evaluate whether secretoneurin represents a sensory neuropeptide innervating the anterior segment of the eye. METHODS: The presence and distribution of secretoneurin was investigated in human eyes by radioimmunoassay and immunofluorescence and compared with that of the rat eye. The source of secretoneurin-positive nerves in the eye was established by measuring the concentration in eye tissues, the trigeminal and superior cervical ganglia both in control rats and in rats treated with capsaicin, and by performing immunofluorescence in one rat subjected to sympathectomy. In the rat trigeminal ganglion, the corresponding mRNA was verified by in situ hybridization and the processing of secretogranin II into secretoneurin by gel filtration chromatography. RESULTS: In human eyes, the highest levels of the peptide were found in the choroid. Nerve fibers were visualized in both species in the upper corneal and limbal stroma; in the trabecular meshwork; in the ciliary muscle, the ciliary body stroma, and processes; and in clear association with the dilator muscle, which disappeared after sympathetic denervation in rats; and also innervating the sphincter muscle in the iris and the choroidal stroma and surrounding blood vessels. Significant amounts of secretoneurin were present in the rat trigeminal ganglion and rat eye tissues. Capsaicin pretreatment led to a 57.0% +/- 4.3% and 59.1% +/- 11.9% decrease of the concentration in the trigeminal ganglion and the iris/ciliary body complex, respectively. Despite high levels in the rat superior cervical ganglion, sympathetic denervation failed to lower the concentration in eye tissues. The secretogranin II probe labeled numerous small-sized ganglion cells within the rat trigeminal ganglion, and the precursor of the peptide was found to become completely processed into secretoneurin. CONCLUSIONS: Apart from the sympathetically innervated dilator muscle, there is unequivocal evidence that secretoneurin represents a constituent of capsaicin-sensitive sensory neurons in the rat trigeminal ganglion and of unmyelinated C-fibers in the rat iris/ciliary body complex, which indicates a participation of this peptide in the ocular irritative response, a model for neurogenic inflammation in lower mammals. Because of the association of nerves with blood vessels and potent angiogenic properties, secretoneurin may be involved in neovascularization processes.     

风筝皮瓣修复眼睑前层及中面部皮肤缺损

目的 评价风筝皮瓣修复合并或不合并中面部皮肤缺损的眼睑前层缺损的疗效.方法 自2008年1月至2010年3月,以面部皮下组织为蒂,设计"风筝"皮瓣,联合或不联合硬腭黏膜移植,修复合并或不合并中面部皮肤缺损的眼睑缺损共10例.眼睑前层或和中面部皮肤缺损面积为(1.2～6.5)cm2、(0.7～4.0)cm2.其中下眼睑中央水平方向4/5、垂直方向完全全层缺损合并颧颊部皮肤缺损1例,下睑内侧水平方向1/2、垂直方向完全全层缺损、下泪小点下泪小管缺损合并中面部皮肤缺损1例,下睑水平及垂直方向均完全全层缺损合并下泪小点及下泪小管缺损1例,上下睑水平方向完全、垂直方向1/3全层缺损合并上下泪小点泪小管缺损1例,下睑中央水平方向4/5、垂直方向完全全层缺损合并颧颊部皮肤缺损1例,全上眼睑前层及颞部皮肤缺损1例,下睑内侧水平方向1/3、垂直方向1/5前层缺损1例,上下睑中央水平方向2/3、上睑垂直方向1/3,下睑垂直方向2/3全层缺损1例,上下睑内侧1/3前层及内呲内侧皮肤缺损合并上下泪小点缺损1例,外眦外侧前层及颞部皮肤缺损1例.结果 皮瓣均无张力修复缺损,皮瓣及硬腭黏膜均全部成活,眼睑外形、功能完全恢复.结论 风筝皮瓣是修复眼睑缺损及面部皮肤缺损的良好方法.

Abstract：

Objective To evaluate the effect of rehabilitating the anterior 1amella of eyelids and midfacial skin defects with kite flap.Methods From January 2008 to March 2010,with or without combination of a hard palate mucosal grafts,the kite flap on a subcutaneous pedicle have been used to repair defect in the anterior lamella of eyelids and midfacial skin in 10 patients.The area of the defect in the anterior lamella of eyelids and midfacial skin ranged from(1.2～6.5)×(0.8～4)cm.Among them,defects span central 4/5 in horizontal direction and complete in vertical direction in full-thickness lower eyelid and partes zygomatica skin in 2 patient,medial 1/2 in horizontal direction and complete in vertical direction and puncta and canaliculus in full-thickness lower eyelid and midface skin in 1 patient,complete lower eyelid and inferior puncta and canaliculus in 1 patient,complete in horizontal direction and 1/3 in vertical direction and puncta and canaliculus both in full-thickness upper and lower eyelids in 1 patient,complete anterior layer of upper eyelid and temples skin in 1 patient,medial 1/3 in horizontal direction and 1/5 in vertical direction in the anterior lamella of lower eyelid in 1 patient,central 2/3 in horizontal direction and 1/3 in vertical direction in full-thickness upper eyelid,and central 2/3 in horizontal direction and 2/3 in vertical direction in full-thickness lower eyelid in 1 patient,medial 1/3 of anterior lamella and puncta and canaliculus both in upper and lower eyelid and inside skin of medial canthus in 1 patient,outside skin of outer canthus and temples skin in 1 patient.Results All flaps and hard palate mucosal grafts were survived.All defects were repaired without tention.The cosmetic appearance and function of eyelids rehabilitated.Conclusions The kite flap provides a competitive method for repairing the anterior lamella of eyelids and facial skin defects.     

Trachoma: 1985 update in Western Australia

Aboriginal preschool and school children were surveyed in the Eastern Goldfields Region and the Eastern Kimberley Region of Western Australia between 1979 and 1985. Statistics from these surveys show that there has been an apparent change in pattern of follicular trachoma since the National Trachoma and Eye Health Programme in some of the communities. The prevalence of follicular trachoma in the 0 to 9 year old age groups had declined from 26.4% in 1977 to 8.8% in 1984/1985 in the Eastern Goldfields and Red Centre combined (0.10 greater than p greater than 0.05). The prevalence reduction occurred in areas where there have been improvements in school hygiene and housing. The prevalence of cicatricial trachoma has also apparently declined from 65% in 1977 to 39% in 1985 in the Red Centre, from 39% in 1977 in the Eastern Goldfields to 21.7% in 1985, and from 58% in 1977 to 24.9% in 1985 in the Eastern Kimberley, Communities at risk were identified and recommendations made for frequency of continued screening, depending on age, distribution and location.     

Cortical processing of visual motion in young infants

High-density EEG was used to investigate the cortical processing of a rotating visual pattern in 2-, 3-, and 5-month-old infants and in adults. Motion induced ERP in the parietal and the temporal-occipital border regions (OT) was elicited at all ages. The ERP was discernable in the 2-months-olds, significant and unilateral in the 3-month-olds and significantly bilateral in the 5-month-olds and adults. The motion induced ERP in the primary visual area was absent in the 2-month-olds and later than in the OT area for the 3-month-olds indicating that information to OT may be supplied by the V1 bypass at these ages. The results are in agreement with behavioural and psychophysical data in infants.     

我国眼视光学近五年发展状况及展望

本文主要回顾了我国近五年来眼视光学领域科学研究的状况,展示我国在近视基础研究和视觉科学应用研究方面的进步和成就,分析科学研究对解决临床视觉问题的指导作用和对大众眼保健的重要意义.本文通过展示具体研究现状和成果表明:眼的生物和光学双重属性赋予眼视光学研究的鲜明特色,多学科交叉合作进一步推动了眼视光学和视觉科研领域的创新.今后,我国眼视光学和视觉科学领域将直面更多的原创性和系统性研究工作,近视防治仍然是该领域长期而艰难的攻关课题.     

Immunohistologic properties of benign and malignant mixed tumor of the lacrimal gland.

We studied the immunohistopathologic features of normal lacrimal gland, benign mixed tumor, and malignant mixed tumor of the lacrimal gland. Primary antisera were to keratin, muscle-specific actin, vimentin, and glial fibrillary acid protein. Keratin stained in occasional myoepithelial cells in normal gland, ductal epithelium in normal gland and the tumors, and occasional stromal epithelioid cells in the tumors. Muscle-specific actin stained in myoepithelium and vascular smooth muscle in normal gland and the tumors, and occasional spindle-shaped and clusters of stromal cells in the tumors. Vimentin staining was nonspecific. Glial fibrillary acid protein stained in occasional myoepithelial cells in normal gland and polyhedral stromal cells in benign mixed tumor. Our findings indicate that ductal epithelium develops into the epithelial component, and some cells in the stroma and myoepithelium develop into some cells in the stroma of benign and malignant mixed tumor of the lacrimal gland.     

Possibilities of spontaneous regression in active phase of ROP

PURPOSE: To evaluate the possibilities of spontaneous regression of changes in the retina and vitreous in active stage 1-5 retinopathy in prematurity. MATERIAL AND METHODS: 168 premature infants with active stages 1-3 and 91 with stages 4-5 ROP, was observed by the author in years 1995-2002. RESULTS: Spontaneous regression of changes in the retina and vitreous was observed in 85% of children with stage 1, in 56% in stage 2 and in 25% in stage 3. In stage 3 regression occurred in 35% in stage 3 A, in 18% in 3 B and in 12% in stage 3 C. With changes in zone III regression can be expected in 95%, in zone II in 45% and in zone I in 6%. Spontaneous reattachment of the retina was observed in 27% of children with stage 4A, in 15% with stage 4B and only in 6% in stage 5. CONCLUSIONS: Considering the occurrence of spontaneous regression, laser therapy should be performed in every stage, if changes are observed in zone I and in every case of stage 3 B and 3 C.     

眼压作为眼部交感神经非对称性的指征

目的:以眼压为指征来明确眼部的交感神经活性的非对称性。方法:在回顾性横断面研究中,对150名新生儿、80名年轻人和159名老年人表面麻醉后使用Tono-pen笔式眼压计测量眼压。结果:在新生儿的眼压右眼16.16mmHg、左眼15.79mmHg,在年轻人的眼压右眼是15.04mmHg、左眼14.71mmHg,在老年人的眼压右眼是15.16mmHg、左眼15.03mmHg。右眼眼压具有统计学差异的是新生儿(P=0.03)和年轻人(P=0.02),在老年人是没有统计学差异(P=0.26)。右眼更高的眼压表明其交感神经活性的降低。结论:我们猜测在双侧器官存在的交感神经活性非对称性是有助于建立身体器官的优势模式。     

I型和II 型胶原在正常角膜和圆锥角膜中的表达

目的　观察正常人及圆锥角膜中 I、II型的表达 ,探讨胶原 I、II型在圆锥角膜病变中的变化。方法　采用免疫组织化学 - SA BC法检测角膜组织中胶原 I、II型胶原的表达。结果　胶原 I型在正常角膜和圆锥角膜的上皮层、实质层及内皮层均有阳性表达 ,但圆锥角膜比正常角膜的表达弱 ;而胶原 II型在正常角膜和圆锥角膜组织的基质层和 Bow m an层均可检测到 ,但圆锥角膜中 II型胶原表达减低 ,在圆锥角膜基质斑块状瘢痕区 II型胶原呈强阳性表达。结论　 I、II型胶原的减少会导致角膜的稳定性降低 ,使角膜的机械抵抗力减弱 ,并使角膜前凸变薄。     

Neurokinin a is a main constituent of sensory neurons innervating the anterior segment of the eye

PURPOSE: To study the innervation pattern of the anterior segment of the eye by neurokinin (NK)-A-immunoreactive nerves and to determine their sensory origin. METHODS: The presence and distribution of NKA was examined in human eyes by radioimmunoassay and immunofluorescence. The source of nerves was determined by measuring the concentration of NKA in the trigeminal ganglion (TG) in comparison with that of the classic sensory peptides substance P (SP) and calcitonin gene-related peptide (CGRP) and in eye tissues in capsaicin-pretreated rats versus control subjects. The NKA-like immunoreactivities were further characterized by reversed phase HPLC in the rat TG and the human iris-ciliary body complex. The presence of gamma-PPT-A mRNA was studied in the rat TG by in situ hybridization. RESULTS: The levels of NKA in human eye tissues were approximately 10 times higher than those of SP but lower than those of CGRP. Nerve fibers were visualized in the cornea, the trabecular meshwork, the iridial stroma, and, prominently, in the sphincter muscle, the ciliary body stroma and muscle and processes, and the choroidal stroma and surrounding blood vessels. In the rat TG, the concentration of NKA was approximately five times higher than that of SP. Capsaicin led to a >60% decrease of the concentration of the peptide in the rat TG and rat eye tissues except for the retina. NKA-like immunoreactivities were present in a single peak corresponding to synthetic NKA, both in the rat TG and in the human iris-ciliary body complex, and numerous ganglion cells of small size were labeled by a gamma-PPT-A probe in the rat TG. CONCLUSIONS: The present results clearly demonstrate that NKA is a main constituent of sensory neurons innervating the anterior segment of the eye. The presence of the peptide in C fibers in ocular tissues indicates a participation in sensory transmission and an involvement in the irritative response in the eye, a model for neurogenic inflammation in lower mammals.     

Dorzolamide effect on ocular blood flow

PURPOSE: To evaluate the effect of dorzolamide on ocular blood flow in normal and glaucomatous eyes. METHODS: Twenty-six eyes with documented open-angle glaucoma of 26 patients and 13 normal control eyes of 8 age-matched subjects were included in this study. All eyes underwent color Doppler imaging for measuring peak-systolic velocity, end-diastolic velocity, and resistance index in the ophthalmic and central retinal arteries and the maximal and minimal velocities in the central retinal vein. Eyes were grouped in control and initial and advanced glaucoma categories. Measurements were made in all groups before and after application of topical dorzolamide. Intragroup comparisons between baseline and dorzolamide conditions were made using paired Student's t-test. Intergroup comparisons under baseline conditions between normal and glaucomatous eyes were made by using the one-way ANOVA test. Statistical significance was set at P < 0.05. RESULTS: The peak-systolic velocity of the central retinal artery in glaucomatous eyes and the end-diastolic velocity of the ophthalmic and central retinal arteries in all groups were significantly higher after application of dorzolamide. The minimal velocity of the central retinal vein showed significantly higher values after dorzolamide, whereas the maximal velocity remained unchanged. The peak-systolic velocity of the ophthalmic artery in all groups and the peak-systolic velocity of the central retinal artery in normal eyes also remained unchanged. The resistance index was significantly lower in the ophthalmic and central retinal arteries in all groups after dorzolamide. The intraocular pressure was significantly reduced in all groups after dorzolamide. Under baseline conditions normal control eyes and glaucomatous eyes showed differences in various measurements. Peak-systolic velocity was significantly lower in glaucomatous eyes than in normal control eyes with the exception of the ophthalmic artery in the initial glaucoma group. End-diastolic velocity was lower in glaucomatous eyes than in control eyes in both arteries. Maximal and minimal velocities of the central retinal vein were lower in glaucomatous eyes than in normal control eyes. Resistance index was higher in glaucomatous eyes than in normal control eyes in the ophthalmic artery but not in the central retinal artery. CONCLUSIONS: Most hemodynamic parameters of intraocular and periocular vessels improve after application of topical dorzolamide in both normal control and glaucomatous eyes. Dorzolamide should be regarded as a useful drug for treatment of glaucoma not only because it reduces intraocular pressure but also because it improves the ocular blood supply.     

Insulin-like growth factor-I and its receptor in neovascular age-related macular degeneration

PURPOSE: The insulin-like growth factor (IGF)-I protein is a growth-promoting polypeptide that can act as an angiogenic agent in the eye. The purpose of the current study was to localize the expression of IGF-I and its receptor (IGF-IR) mRNA and IGF-IR protein in situ in the normal human eye and to examine the presence of expression in eyes with neovascular age-related macular degeneration (AMD). METHODS: Formalin-fixed, paraffin-embedded slides of 4 normal control eyes and 14 eyes with choroidal neovascularization (CNV) secondary to AMD were examined. Three eyes with proliferative diabetic retinopathy were studied as the positive control. IGF-I and IGF-IR mRNA was detected by in situ hybridization with digoxigenin-labeled RNA probes. IGF-IR protein was studied by immunohistochemistry. RESULTS: In the normal retina, IGF-I and IGF-IR mRNA expression was found throughout the neuroretinal layers, in the retinal pigment epithelium (RPE), and in some choriocapillary and retinal capillary endothelial cells. In eyes with CNV we found IGF and IGF-IR mRNA in capillary endothelial cells, some transdifferentiated RPE, and fibroblast-like cells. IGF-IR protein was found in normal eyes in all neuroretinal layers, in the RPE, and in the choroidal vessels. In eyes with CNV, IGF-IR protein was present in the RPE monolayer, in transdifferentiated RPE, and in newly formed vessels. CONCLUSIONS: The colocalization of protein and receptor indicates an autocrine function of IGF-I in the normal human retina. Because IGF-I participates in ocular neovascularization, synthesis of IGF-IR and IGF-I in endothelial cells, RPE cells, and fibroblast-like cells in CNV may point toward a role for this growth factor in the pathogenesis of neovascular AMD.     

Ultrastructural localization of collagen IV, fibronectin, and laminin in the trabecular meshwork of normal and glaucomatous eyes.

PURPOSE: To determine whether differences in the ultrastructural characteristics or composition of the basement membranes of the trabecular lamellae and Schlemm's canal exist in normal eyes and eyes with primary open-angle glaucoma (POAG). Basement membranes play key roles in the attachment of the overlying trabecular cells and Schlemm's canal cells. METHODS: Electron microscopy used in conjunction with immunogold labeling was used to examine the ultrastructure of the basement membranes in the trabecular meshwork and to determine the presence of collagen IV, laminin, and fibronectin in 6 normal eyes and 6 eyes with POAG. To determine which cells in the meshwork synthesized these molecules in situ hybridization was studied in an additional 8 normal eyes. RESULTS: No distinctive ultrastructural changes were found in the basement membranes of glaucomatous eyes, whether early or advanced disease, when compared with normal eyes. Label for all three proteins was present in the basement membranes of the trabecular lamellae, Schlemm's canal, and in scattered patches within the juxtacanalicular tissue. Laminin and fibronectin were most abundant in the periphery of the sheath material surrounding the elastic tendons in the juxtacanalicular tissue. In contrast to previously published light microscopic studies, no increase in fibronectin was found in glaucoma. Regions of the basement membrane of the canal underlying giant vacuoles were similar to regions without giant vacuoles in both appearance and labeling. In situ hybridization revealed that mRNA for all three proteins was present in most trabecular cells throughout the meshwork; no regional differences in cellular labeling within were observed. CONCLUSION: The ultrastructural characteristics and immunogold labeling of basement membranes were similar in normal and glaucomatous eyes; no additional structures were labeled in POAG eyes that were not also labeled in normal eyes. Label of the patches of amorphous fibrogranular material within the juxtacanalicular tissue suggests it is basement membrane in origin, while the sheath material which is known to accumulate in POAG was not heavily labeled and does not appear to be basement membrane in origin.     

Expression and localization of angiogenic inhibitory factor, chondromodulin-I, in adult rat eye

PURPOSE. To determine the role in the eye of chondromodulin (ChM)-I, which has been identified in cartilage as an angiogenic inhibitor, the expression and localization and a possible function of ChM-I were investigated. METHODS. Expression and localization of ChM-I in rat eyes were examined by RNase protection assay and in situ hybridization and by immunostaining, using an antibody against a synthetic peptide. The effect of recombinant ChM-I on tube morphogenesis of retinal endothelial cells was examined in culture. RESULTS. The rat ChM-I gene was determined to encode the open reading frame of 334 amino acid residues, and ChM-I mRNA was exclusively expressed in cartilage, eye, and cerebellum in rats. ChM-I mRNA expression was evident in the iris-ciliary body, retina, and scleral compartments, but not in other compartments of the eye. In situ hybridization revealed mRNA expression in the ganglion cells, inner nuclear layer cells, and pigment epithelium in the retina and in the nonpigment epithelium of the ciliary body. Immunoreactive ChM-I was present in these cells and also in the vitreous body. Western blot analysis detected an approximately 25-kDa band of ChM-I presumed as a secretory form in the aqueous humor and vitreous body and an approximately 37-kDa band as a precursor form in the retina. Recombinant human ChM-I inhibited tube morphogenesis of human retinal endothelial cells in vitro. CONCLUSIONS. These observations indicate a potential role for ChM-I in inhibition of angiogenesis in the rat eye.     

Characterization of semenogelin proteins in the human retina

Semenogelin I and II are the major proteins present in semen coagulum. In the present study, semenogelin I and II were detected in human RPE lysates by proteomic analysis. We further analyzed the expression of these proteins in the retinal cells in vivo and in vitro. Western blots detected semenogelin I and II in both RPE and neural retina while the vitreous contained only SgII. Cryo and paraffin sections of human retina were processed for both immunofluorescence and DAB reaction with an antibody that recognizes both forms of semenogelin proteins. Retina and RPE total lysates were evaluated for the presence of these proteins and in a human RPE cell line (D407). Both proteins were detected by western blot in human RPE and in D407 cell lysates. Immunoreactivity was detected in the ganglion cell and photoreceptor layer of the retina. Our data support the expression of semenogelin I and II in the human retina in several different compartments. Further studies towards addressing the function of these proteins in the retina are in progress.     

新世纪我国斜视弱视研究进展

近5年来,在中华医学会眼科学分会的指导和全体专业人员的共同努力下,我国斜视、弱视基础和临床研究取得了长足进步。我们的科研人员和临床工作者在弱视分子和神经机制研究、视觉发育的可塑性研究、弱视的脑功能成像研究、眼外肌滑车（Pulley）研究以及斜视弱视的诊断、治疗及流行病学研究方面均付出了辛苦的劳动,取得了丰硕的成果。我们期待在未来的10年中,本学科的工作能不断发展、不断提高。     

Polyamines in normal and cataractous human lenses: Evidence for post-translational modification

The polyamine composition of normal and cataractous human lenses has been studied. Polyamines (putrescine, spermidine and spermine) have been shown to occur in the unbound form in the acid-soluble fraction and in the bound form in the acid-insoluble fraction of the lens. It has also been shown that only putrescine occurs in both conjugated and non-conjugated states in the lens, while putrescine as well as spermidine occur in both forms in the aqueous fluid. Estimation of the polyamine content in cataractous lenses indicates elevated levels of both bound and unbound polyamines in these lenses in comparison to the normal lenses. Evidence is presented which indicates an increase in the level of polyamines covalently bound to protein, in a γ-glutamyl linkage, in the cataractous lens.     

Intraocular and cardiovascular effects of calcitonin gene-related peptide (CGRP)-I and -II in the rabbit.

Calcitonin gene-related peptide (CGRP) is a 37-amino acid neuropeptide localized in the eye in the sensory nerves. In this study, the physiological effects of the two naturally occurring forms of human CGRP, CGRP-I, and -II, which differ only in three amino acids, have been demonstrated in the rabbit eye and cardiovascular system. Intravenously administered CGRP-I caused a biphasic increase in the intraocular pressure (IOP), disruption of the blood-aqueous barrier, and increase in the cyclic adenosine 3',5'-monophosphate (cAMP) content in the aqueous humor. CGRP-II caused a monophasic increase in the IOP and disruption of the blood-aqueous barrier, but no increase in the cAMP content occurred. CGRP-I and -II decreased the blood pressure in a similar dose-dependent manner. The effects of intracamerally administered CGRP-I and -II were very similar in the eye. An increase in the IOP, breakdown of the blood-aqueous barrier, and an increase in the cAMP content in the aqueous humor occurred. The differences in the biological responses between CGRP-I and -II in the rabbit eye might be a result of the different affinities of the CGRP forms to a single receptor. Alternatively, different subtypes of receptors for CGRP-I and -II may exist in the rabbit.     

Reassessment of histochemistry of retinal glycogen.

Disadvantages in classical methods employed in the histochemical study on retinal glycogen were overcome by the freeze-drying and chromic acid-PAS method. They made it possible to prevent artificial diffusion of water soluble glycogen out of the tissue, and to distinguish glycogen from nonglycogenous components without the saliva test.Glycogen was most abundant in the monkey and rabbit retinas, considerable in the human and cat and less in the rat, suggesting that the amount of glycogen in different species is not always correlate with inefficiency in vasculature of the retina.Heavily concentrated glycogen was found in the myoid of cones in the human and the monkey retina, and it disappeared completely from the latter after cautery of the posterior ciliary arteries. Abundant glycogen in the inner layers of the rabbit retina also disappeared completely after the operation.The role of glycogen in retinal physiology in anoxia resulting from defective choroidal circulation is discussed.     

Expression and distribution of matrix metalloproteinases and their inhibitors in the human iris and ciliary body

AIM: To determine the expression and distribution of matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) in the normal human iris and ciliary body. METHODS: Seven postmortem human eyes were fixed with formalin. The iris and ciliary body were dissected out and embedded in paraffin. The expression of MMPs -1, 2, 3, and 9, and TIMPs 1-4 in the iris and ciliary body was determined by a novel immunofluorescence technique and the results graded by masked observers. RESULTS: Positive staining for MMPs and TIMPs was observed in all regions of the anterior uvea, and was more intense in the ciliary body than in the iris. Most MMPs and TIMPs showed similar patterns in their distribution. In the ciliary body, staining was strongest in the epithelium, and was localised to the epithelial cell cytoplasm, except for TIMP-3 which was strongly expressed in the basement membranes. In the iris, staining was most noticeable in the anterior border and anterior epithelial layer. Blood vessels in the stroma of the iris and ciliary body also stained moderately for MMPs and TIMPs. CONCLUSION: Both MMPs and TIMPs are widely expressed in the anterior uvea, with a positive correlation between their expressions. Their differential localisation in the ciliary body suggests they may have a role in maintaining homeostasis in the uveal tract.