Biomedical subjects

Josef Flammer

Publications and source records attributed to Josef Flammer.

At least 55 records · Page 3Linked to original sources

PubMed2003

Experience with Cosopt, the fixed combination of timolol and dorzolamide, after switch from free combination of timolol and dorzolamide, in Swiss ophthalmologists' offices.

PURPOSE: To analyse a response to the therapy switch from the concomitant application of beta-blocker and topical carbonic anhydrase inhibitor to the fixed combination of timolol and dorzolamide (Cosopt) in glaucoma/ocular hypertensive patients under everyday, office-practice conditions. PATIENTS AND METHODS: The data source was a survey among practising ophthalmologists in Switzerland assessing their experience with glaucoma patients/ocular hypertensives put for the first time on the fixed combination of timolol and dorzolamide. A total of 98 patients underwent the therapy switch in at least one eye. The intraocular pressure (IOP) change between the baseline visit before switch to the timolol-dorzolamide fixed combination occurred, and the first follow-up control after the switch, served as an indicator of compliance. RESULTS: The IOP decreased on average from 19.43 +/- 5.64 mmHg to 17.97 +/- 3.58 mmHg (p < 0.01). The time to the follow-up visit ranged from 4 to 354 days, and the magnitude of IOP change demonstrated a significant dependence on the time to the follow-up visit, also when corrected for baseline IOP level. A total of 87 (85.3%) continued on the timolol-dorzolamide fixed combination therapy after the first control visit. In 68 of these 98 patients the contralateral eyes underwent the same therapy switch, and their IOP followed an identical pattern of behaviour. CONCLUSION: The average IOP decrease of 1.5 mmHg upon therapy switch to the timolol-dorzolamide fixed combination suggests a better efficacy due to improved compliance. Short-term compliance benefit seems to be more pronounced. The high timolol-dorzolamide fixed combination therapy continuation rate reflects an improvement in compliance and subjectively-perceived convenience.

Adrenergic beta-Antagonists↗

PubMed2002

Increased plasma levels of 20S proteasome alpha-subunit in glaucoma patients: an observational pilot study.

PURPOSE: Several reports have shown that proteasome levels may change during pathological processes. Here we investigated whether altered gene expression of the alpha-subunit of 20S proteasomes in leukocytes of glaucoma patients at the level of mRNA, shown by us earlier, is reflected by the level of protein synthesis. METHODS: Western blot analysis was performed to determine the protein levels of the 20S proteasome alpha-subunit in leukocytes of 12 glaucoma patients (6 HTG and 6 NTG) and 6 healthy controls. RESULTS: Plasma levels of the 20S proteasome alpha-subunit showed a 3.4+/-0.47 (mean+/-SD; p<0.0001) fold increase in glaucoma patients when compared to healthy controls. In addition, normal tension glaucoma patients revealed a more pronounced alpha-subunit expression (p<0.05) when compared to patients with high tension glaucoma. CONCLUSIONS: During the pathological process of glaucoma, proteasome protein levels increase. This indicates that proteasome protein levels may be a diagnostic or eventually a prognostic marker for glaucomatous damage.

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PubMed2002

Vascular dysregulation in the choroid of subjects with acral vasospasm.

OBJECTIVE: To assess the relationship between ocular perfusion pressure and blood flow in the choroid in subjects with acral vasospasm. PATIENTS AND METHODS: Twenty otherwise healthy subjects with acral vascular dysregulation and 55 age-matched nonvasospastic healthy volunteers were recruited. After a 20-minute rest in a sitting position, intraocular pressure and choroidal blood flow were determined by means of applanation tonometry and choroidal laser Doppler flowmetry, respectively. The laser Doppler flowmetry variables velocity, volume, and flux were assessed. The correlations between mean ocular perfusion pressure ([23 x [(23 x diastolic blood pressure) + (13 x systolic blood pressure)]] -intraocular pressure) and blood flow measures were determined by means of the Pearson linear correlation factor. The t test was used to evaluate differences between normal subjects and patients with vasospasm. RESULTS: Apart from a slight difference in systolic blood pressure (mean +/- SD, 113.70 +/- 11.88 mm Hg in the vasospastic group and 121.09 +/- 14.58 mm Hg in the control group; P =.05), the 2 study groups were completely comparable. Velocity and flux correlated significantly with the mean ocular perfusion pressure (r = 0.76, P<.001; r = 0.64, P =.002, respectively) in vasospastic subjects. Such correlations did not occur in the control group, and the difference between vasospastic patients and control subjects with regard to these correlations was statistically significant (P<.001 and P =.003, respectively). CONCLUSIONS: Choroidal blood flow seems, to some degree, to be independent of perfusion pressure, but not in subjects with acral vasospasm.

Blood Flow Velocity↗

PubMed2002

Increased endothelin-1 plasma levels in giant cell arteritis: a report on four patients.

PURPOSE: To test the hypothesis that endothelin-1 is increased in giant cell arteritis. METHODS: Interventional case series. The medical history of four patients who presented to the University Eye Clinic Basel, Switzerland, with giant cell arteritis is reported. Endothelin-1 plasma levels were measured in all patients. The relevant medical literature was reviewed. RESULTS: All patients presented with typical histopathological signs of giant cell arteritis in the temporal artery biopsy. The erythrocyte sedimentation rate was increased in two patients. All patients showed significantly increased endothelin-1 plasma levels, ranging between 3.13 to 4.82 pg/ml (reference value for females: 1.42 pg/ml +/- 0.28 standard deviation, for males: 1.67 pg/ml +/- 0.34 standard deviation). CONCLUSION: The data obtained from the patients so far examined indicate that the level of circulating endothelin-1 is increased in giant cell arteritis. The clinical relevance of such an increase needs to be further evaluated.

Aged↗

PubMed2002

The impact of ocular blood flow in glaucoma.

Two principal theories for the pathogenesis of glaucomatous optic neuropathy (GON) have been described--a mechanical and a vascular theory. Both have been defended by various research groups over the past 150 years. According to the mechanical theory, increased intraocular pressure (IOP) causes stretching of the laminar beams and damage to retinal ganglion cell axons. The vascular theory of glaucoma considers GON as a consequence of insufficient blood supply due to either increased IOP or other risk factors reducing ocular blood flow (OBF). A number of conditions such as congenital glaucoma, angle-closure glaucoma or secondary glaucomas clearly show that increased IOP is sufficient to lead to GON. However, a number of observations such as the existence of normal-tension glaucoma cannot be satisfactorily explained by a pressure theory alone. Indeed, the vast majority of published studies dealing with blood flow report a reduced ocular perfusion in glaucoma patients compared with normal subjects. The fact that the reduction of OBF often precedes the damage and blood flow can also be reduced in other parts of the body of glaucoma patients, indicate that the hemodynamic alterations may at least partially be primary. The major cause of this reduction is not atherosclerosis, but rather a vascular dysregulation, leading to both low perfusion pressure and insufficient autoregulation. This in turn may lead to unstable ocular perfusion and thereby to ischemia and reperfusion damage. This review discusses the potential role of OBF in glaucoma and how a disturbance of OBF could increase the optic nerve's sensitivity to IOP.

Eye↗

PubMed2002

Forskolin upregulation of NOS I protein expression in porcine ciliary processes: a new aspect of aqueous humor regulation.

BACKGROUND: To determine whether nitric oxide synthase (NOS) protein expression can be modulated by forskolin in porcine ciliary processes. METHOD: Western blot analysis using mouse monoclonal antibodies against NOS I (neuronal NOS or nNOS), NOS II (macrophage NOS or macNOS), and NOS III (endothelial NOS or eNOS) was performed in porcine ciliary processes. Expression of NOS I and II was also assessed in the presence or in the absence of 1 microM forskolin exposure (4 and 24 hours). RESULTS: All three NOS isoforms could be detected in isolated porcine ciliary processes. Protein expression for NOS I was about 6 times higher than for NOS III and 15 times higher than for NOS II. In comparison to controls, after forskolin exposure, NOS I protein expression was increased by about 1.5-fold. No change could be observed in NOS II protein expression after forskolin exposure. CONCLUSIONS: Nitric oxide is involved in transepithelial fluid transport of different organs (lung, kidney, colon, etc.) and is suspected to play a role in ciliary processes by modulating the aqueous humor production. The present study indicates that forskolin (which increases cAMP production) modulates NOS I protein expression in isolated porcine ciliary processes. These results suggest that selective inhibition of NOS I could be tried for reducing aqueous humor production. The clinical relevance requires further investigations.

Animals↗

PubMed2002

The beta-blocker carteolol inhibits contractions induced by KCl in pig ciliary arteries: an effect modulated by extracellular Ca++.

BACKGROUND: To assess if the vasorelaxing properties of the ocular hypotensive beta-blocker carteolol could share some pharmacological features of calcium-channel antagonists in isolated porcine ciliary arteries. METHODS: In a myograph system (isometric force measurement), quiescent vessels were contracted with increasing concentrations of potassium chloride (KCl: 4.7 - 30 mM) in the presence of different concentrations of extracellular calcium (Ca (++): 0 - 10 mM) and/or carteolol (0 - 1 mM). Vessels precontracted with 20 mM KCl were exposed (cumulative manner) to carteolol (0.03 - 3 mM) in the presence of different concentrations of Ca (++) (0.25, 2.5, 10 mM). Contractions and relaxations are expressed in percent of 100 mM and 20 mM KCl-induced contractions, respectively (mean +/- SEM). RESULTS: Contractions induced by 30 mM KCl (99.0 +/- 4.8 %) were abolished in the absence of Ca (++) and markedly inhibited in the presence of carteolol (1 mM: 40.6 +/- 4.0 %). The inhibitory effect of carteolol on KCl-induced contractions was potentiated (0.25 mM: 6 +/- 2 %) by decreasing and reversed (10 mM: 94 +/- 5 %) by increasing Ca (++) concentrations. Vessels precontracted with KCl were relaxed by carteolol (maximum: 82 +/- 9 %), an effect potentiated (102 +/- 10 %) by lowering or inhibited (27 +/- 11 %) by increasing Ca (++) concentrations. DISCUSSION: The present in vitro pharmacological study, for which in principle no clinical interpretation should be made, suggests that carteolol shares, at rather high concentrations, some characteristics that apparently could mimic certain effects of calcium-channel blockers.

Adrenergic beta-Antagonists↗

PubMed2002

Effect of Xalatan(R) and Cosopt(R) on the vascular tone of quiescent isolated pig ciliary arteries.

BACKGROUND: To investigate whether dilutions of the commercially available Xalatan(R) or Cosopt(R) induce vasoconstrictions in isolated quiescent porcine ciliary arteries. MATERIAL AND METHODS: Contractions measured with a myograph system (isometric force measurement) were expressed in percent of 100 mM potassium chloride(KCl)-induced contraction (mean +/- standard error). In preliminary experiments, vessels were contracted with 100 mM KCl after previous exposures to different dilutions of Xalatan(R) (1/250 to 1/50) or Cosopt(R) (1/500 to 1/5). In a further series of experiments, vessels were exposed in a cumulative manner to different dilutions of Xalatan(R) or Cosopt(R) (1/50 000 to 1/166). RESULTS: Contractions induced by 100 mM KCl were not significantly affected by previous exposure to Xalatan(R) or Cosopt(R) at dilutions higher than 1/166 and 1/50, respectively. However, at the lower dilutions tested, 100 mM KCl-induced contractions were significantly (p < 0.001) and markedly inhibited (1/50 Xalatan(R): 22.1 +/- 2.8 %; 1/5 Cosopt(R): 24.8 +/- 4.6 %). In quiescent vessels, diluted (1/50 000 to 1/166) preparations of Xalatan(R) induced, in a dilution-dependent manner, statistically significant (p < 0.05) but, however very small (3.2 +/- 1.0 %) contractions in comparison to Cosopt(R) (- 0.6 +/- 0.2 %). CONCLUSIONS: Although on the basis of these in vitro experiments no clinical interpretation should be made, at very high dilutions that did not affect KCl-induced contractions, Xalatan(R), but not Cosopt(R), had a very small vasoconstrictive effect in isolated quiescent porcine ciliary arteries. At low dilutions, responses to KCl were inhibited, possibly in relation to an unclear effect of the excipients of Xalatan(R) and Cosopt(R).

Animals↗

PubMed2002

Effect of palmitoleic acid on bradykinin-induced endothelium-dependent relaxation in isolated pig ciliary artery.

BACKGROUND: Endothelial-dependent relaxation has been reported to be impaired in some normal tension glaucoma patients. The present study investigates whether the gap junction uncoupling agent palmitoleic acid (PA) affects bradykinin-induced endothelium-dependent relaxation in isolated pig ciliary artery. MATERIAL AND METHODS: In a myograph system (isometric force measurement), vessels precontracted with the thromboxane A2 agonist U 46619 ( approximately 0.1 micrometer) were relaxed by increasing concentrations (cumulative) of bradykinin (0.003 - 3 micrometer). Experiments were repeated in the presence of 100 micrometer L-NAME (inhibitor of nitric oxide formation) and/or 100 micrometer PA. Some experiments were conducted in vessels with a non-functional endothelium (intentionally and mechanically damaged). All experiments were conducted in the presence of 10 microM indomethacin (cyclooxygenase inhibitor). RESULTS: In a concentration-dependent manner, bradykinin evoked a relaxation (101 +/- 2 %) that was abolished in vessels with a non-functional endothelium (maximal relaxation: 7 +/- 1 %, p < 0.001). In the presence of L-NAME, relaxations induced by bradykinin were almost completely inhibited (maximal relaxation: 25 +/- 5 %, p < 0.001). Relaxations evoked by bradykinin were not significantly affected by PA (either in the presence or in the absence of L-NAME). CONCLUSIONS: The bradykinin-induced relaxation, known to be associated in porcine ciliary arteries with an electrical coupling between endothelial and smooth muscle cells, appears to be unaffected by the gap junction uncoupling agent palmitoleic acid. Further investigations are needed to understand the physiology of the endothelium-dependent ocular blood flow modulation that is considered to be dysregulated in some glaucoma patients.

Animals↗

PubMed2002

[Reproducibility of measurements with the retinal vessel analyzer under optimal conditions].

BACKGROUND: [corrected] To evaluate the reproducibility of measurements with the Retinal Vessel Analyzer (RVA) in healthy subjects and to describe which measuring conditions should be guaranteed to obtain optimal results. METHODS: The diameter of retinal arteries and veins of 20 healthy subjects (M : F = 11 : 9; mean age: 33 +/- 12 years) were measured with the RVA at baseline, after 2 hours, and after 2 weeks. RESULTS: No statistically significant differences in the diameter of retinal arteries and veins between the single measurements were present. Short-term variability of arterial diameter was 1 %, and the intraclass correlation coefficient kappa was 0.96. Long-term variability was 1.8 %, kappa was 0.98. In retinal veins, a short-term variability of 1 % was calculated, with a kappa of 0.97. Long-term variability was 1.5 %, with a kappa of 0.98. CONCLUSION: Due to the high reproducibility of its measurements, the RVA appears to be a useful device for both analysis and follow-up of retinal vessel diameters.

Adult↗

PubMed2002

Effect of melatonin on vascular responses of porcine ciliary arteries.

PURPOSE: To investigate the effect of melatonin on isolated porcine ciliary arteries. METHODS: Isolated porcine ciliary arteries were suspended in myograph chambers filled with modified Krebs-Ringer solution (37 degrees C; 95% O2/5% CO2) for isometric tension recording. RESULTS: In quiescent porcine ciliary arteries with endothelium, melatonin (10(-11)--10(-5) M) evoked no change in vascular tone. The highest concentration of melatonin (10(-4 ) M) evoked a small but significant contraction. In vessels precontracted with U-46619 (10(-7) M), increasing concentrations of melatonin (10(-11)--10(-5) M) did not evoke a response. In precontracted arteries with endothelium, contractile response of vascular smooth muscle to increasing concentrations of serotonin (10(-10)--10(-5) M) and noradrenaline (10(-10)--10(-5) M) was reduced after preincubation with melatonin (10(-4) M). Melatonin (10(-4) M) did not alter the response to endothelin-1 (10(-10)--10( -7) M) and U-46619 (10(-10)--10(-6 ) M) in precontracted arteries with endothelium. CONCLUSION: These findings demonstrate that melatonin attenuates the effect of serotonin and noradrenaline and is itself a mild vasoconstrictor in porcine ciliary arteries. The role of melatonin in human ocular circulation remains to be established.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗

PubMed2002

The effect of losartan potassium on choroidal hemodynamics in healthy subjects.

PURPOSE: To investigate the choroidal hemodynamic effects of losartan potassium, a specific angiotensin II subtype AT1 receptor antagonist. METHODS: In this prospective, randomized, observer-masked, open-label placebo-controlled (lactose), two-period crossover study, the choroidal hemodynamic effects of a single oral 50-mg dose of losartan potassium were evaluated in 12 healthy subjects using choroidal laser Doppler flowmetry. RESULTS: Perfusion pressure and the choroidal laser Doppler flowmetry parameters velocity, volume, and flux did not vary significantly compared with placebo (P = 0.33, 0.31, 0.74, and 0.61, respectively). Correcting choroidal laser Doppler flowmetry parameters for perfusion pressure in a covariance analysis did not change these results. CONCLUSION: A single oral 50-mg dose of the angiotensin II AT1 receptor antagonist losartan potassium given does not disturb the homeostasis of ocular perfusion pressure or choroidal blood flow in young healthy subjects.

Administration, Oral↗

PubMed2002

Sildenafil induces retinal vasodilatation in healthy subjects.

BACKGROUND: The cardiovascular effects of sildenafil (Viagra), a selective inhibitor of phosphodiesterase type 5 (PDE5), have been extensively studied. However, its effect on human retinal arteries and veins has not yet been investigated. The effect of a single dose administration of sildenafil on the retinal vessel diameters of healthy subjects was evaluated. METHODS: Sildenafil 50 mg was administered to 10 healthy subjects (male:female = 4:6; mean age 31 (SD 6) years). The diameters of retinal arteries and veins were measured by means of a retinal vessel analyser (RVA) immediately before and at 30, 60, 90, and 120 minutes after sildenafil uptake. Blood pressure, heart rate, and intraocular pressure were monitored in parallel. RESULTS: A significant increase of 5.8% (p<0.001) in both retinal arterial and venous diameters was found 30 minutes after sildenafil uptake. The diameters returned to baseline after 120 minutes. A mild systemic hypotensive response was seen. Changes in heart rate and intraocular pressure were not observed. CONCLUSION: Sildenafil causes a significant dilatation of retinal arteries and veins in healthy subjects. A possible role for PDE5 in the regulation of retinal blood flow is implicated.

Adult↗

PubMed2002

Reliability of confocal choroidal laser Doppler flowmetry.

PURPOSE: To assess the variability in choroidal laser Doppler flowmetry (LDF). METHODS: Five measurements of choroidal blood flow were obtained on 5 days in both eyes of 10 subjects. Reliability, sensitivity, and sample size calculations were performed. Yield, the intensity of the returning light (direct current [DC]) divided by the signal amplification (gain) used during recording, was calculated (yield = DC/gain). The correlation between yield and the LDF parameters velocity, volume, and flux was analyzed. Reliability, sensitivity, and sample size calculations were repeated after correcting for this relationship. The influence of different light-scattering properties on the returning signal was assessed in a model eye. RESULTS: Yield and the LDF parameters, velocity, volume, and flux, correlated significantly in a regression model. After the influence of yield was partialized out, reliability, reproducibility, sensitivity, and statistical power improved markedly. The high reliability of yield in a given eye (87%) suggests, that, besides varying recording settings on different days, individual specific scattering properties within the eye influence LDF measurements. Comparison of model eye data with human data disclosed a low signal-to-noise ratio with decreasing yield. Correcting for yield did not affect the sensitivity to blood flow changes induced by hypercapnia or a suction cup. CONCLUSIONS: Tissue-scattering properties alter the characteristics of the returning light, and recording settings affect the outcome of the analysis of the returning light during LDF measurements. Partializing out the influence of yield markedly improves the reproducibility of choroidal LDF.

Adult↗

PubMed2002

Inhibition by brimonidine of forskolin-induced nitrite production in isolated pig ciliary processes.

PURPOSE: To investigate by which mechanism the ocular hypotensive drug brimonidine (selective alpha(2)-adrenoreceptor agonist) inhibits the production of nitrite induced by forskolin in isolated porcine ciliary processes. METHODS: Nitrite (a nitric oxide metabolite) was measured by Griess reaction in the medium surrounding the ciliary processes, before and after exposure to different drugs. Tissues were exposed for 120 minutes to forskolin (0.1 microM; an adenylylcyclase activator) or 8-bromo-cAMP (10 microM; a cAMP analogue). Some experiments were conducted in the presence of brimonidine (0.01-10 microM), yohimbine (0.1-10 microM; alpha(2)-adrenoreceptor antagonist), prazosin (10 microM; alpha(1)-adrenoreceptor antagonist), nicergoline (10 microM; an alpha(1)-adrenoreceptor antagonist), propranolol (10 microM; a beta-adrenoreceptor antagonist or beta-blocker), and/or pertussis toxin (2 microg/mL; PTX, a G(i)-protein inhibitor). RESULTS: Nitrite production induced by forskolin (133% +/- 6%), but not that induced by 8-bromo-cAMP (133% +/- 6%), was inhibited in a concentration-dependent manner by brimonidine (10 microM: 103% +/- 4%, P < 0.001; EC(50): 0.05 microM). The inhibitory effect of brimonidine was prevented by PTX (119% +/- 7%, P < 0.01) and, in a concentration-dependent manner, by yohimbine (10 microM: 134% +/- 9%; P < 0.01), but not by prazosin, nicergoline, or propranolol. CONCLUSIONS: Reduction of the formation of aqueous humor in the ciliary body's epithelium (and thus an intraocular pressure decrease) after alpha(2)-adrenergic receptor stimulation by brimonidine is known to be associated with a G(i)-protein-mediated inhibition of adenylylcyclase activity. The present study indicates that, through a similar alpha(2)-adrenoreceptor/G(i)-protein pathway, brimonidine can also inhibit nitrite production after adenylylcyclase activation (forskolin-induced) in isolated porcine ciliary processes.

8-Bromo Cyclic Adenosine Monophosphate↗

PubMed2002

Elevated plasma endothelin-1 levels and vascular dysregulation in patients with rheumatoid arthritis.

BACKGROUND: Contradictory results on plasma endothelin-1 (ET-1) levels in patients with rheumatoid arthritis have been reported in previous studies. We therefore evaluated whether plasma ET-1 levels in patients with rheumatoid arthritis differ from those of normal controls. Since systemically increased levels of ET-1 are known to occur in tandem with primary or secondary vascular dysregulation, we also measured peripheral blood flow by means of nailfold capillaroscopy combined with a cold provocation test. MATERIAL/METHODS: We measured plasma levels of ET-1 in twelve patients with different stages of rheumatoid arthritis by means of a specific radioimmunoassay, and compared ET-1 values to those of healthy controls. Capillary blood flow and the frequency of cold-induced vasospasm were studied in parallel, using nailfold capillaroscopy combined with a cold provocation test. RESULTS: Plasma ET-1 levels were significantly increased in patients with rheumatoid arthritis (p = 0.01) when compared to controls (2.38+/-0.95 pg/ml vs. 1.53+/-0.38 pg/ml). Capillary blood flow was reduced when compared to our own normal values, and a cold-induced blood standstill was seen in 58% of the patients. CONCLUSIONS: Patients with rheumatoid arthritis exhibit significantly elevated levels of ET-1, which may be associated with the symptoms of vascular dysregulation observed in nailfold capillaroscopy. Even though the clinical conclusions should be drawn from this study with caution, additional therapy with calcium channel blockers or, possibly in the future, with ET-1 receptor blockers, may be beneficial in patients with rheumatoid arthritis.

Adult↗

PubMedDate not supplied

A sick eye in a sick body? Systemic findings in patients with primary open-angle glaucoma.

Despite intense research, the pathogenesis of primary open-angle glaucoma (POAG) is still not completely understood. There is ample evidence for a pathophysiological role of elevated intraocular pressure; however, several systemic factors may influence onset and progression of the disease. Systemic peculiarities found in POAG include alterations of the cardiovascular system, autonomic nervous system, immune system, as well as endocrinological, psychological, and sleep disturbances. An association between POAG and other neurodegenerative diseases, such as Alzheimer disease and Parkinson disease, has also been described. Furthermore, the diagnosis of glaucoma can affect the patient's quality of life. By highlighting the systemic alterations found in POAG, this review attempts to bring glaucoma into a broader medical context.

Cardiovascular Diseases↗

PubMedDate not supplied

Human connective tissue growth factor mRNA expression of epiretinal and subretinal fibrovascular membranes: a report of three cases.

PURPOSE: To investigate the correlation between connective tissue growth factor (CTGF) mRNA expression and immunohistochemical characteristics (expression of type I collagen and tenascin) of fibrovascular membranes of proliferative retinal diseases under in vivo conditions. METHODS: CTGF mRNA expression was investigated using in situ hybridization. Expression of type I collagen and tenascin was detected by immunohistochemical staining. RESULTS: CTGF mRNA is produced in transformed retinal pigment epithelial cells and appears also in fibroblast-like cells, which are embedded in epiretinal and subretinal membranes of proliferative retinal diseases as well as in surgically removed subretinal membranes. In all examined membranes, expression of human CTGF mRNA appears in concurrence with the expression of type I collagen and tenascin. CONCLUSIONS: The predominant expression of CTGF mRNA in the development of fibrovascular membranes of proliferative retinal diseases suggests a significant role of CTGF in the pathological course of these ocular disorders.

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