摘要:

The ergoline derivatives, bromocriptine, lergotrile and pergolide, are potent dopaminergic agonists. Topically administered doses of lergotrile and pergolide, ranging from 0.001 to 1% applied unilaterally, produced dose and time-related ocular hypotension in rabbits and monkeys. In contrast, bromocriptine produced moderate ocular hypotension in rabbits but not in monkeys. Lergotrile (1%) produced significant mydriasis in rabbits whereas pergolide (0.01 to 0.1%) produced a slight miosis. Lergotrile and pergolide were also effective in suppressing ocular hypertension induced by water loading in rabbits whereas bromocriptine was relatively ineffective. These data demonstrate that topically administered ergoline derivatives can: 1) lower intraocular pressure in rabbits and monkeys, 2) suppress ocular hypertension induced by water loading in rabbits and 3) alter iris function in rabbits, producing either mydriasis or miosis, presumably by activation of adreno-ceptors.

ISSN:0271-3683    

DOI:10.3109/02713688209000771

出版商:Taylor&Francis    

年代:1982

数据来源: Taylor

摘要:

In vitroadherence ofPseudomonas fluorescensorganisms to the human cornea is correlated with bacterial pili. The role of pili in the attachment to human corneal epithelial cells was studied in anin vitroadherence assay system. A homogeneous, purified pilin preparation showed a molecular weight of 16,500 on SDS-polyacrylamide gels. Within 5 minutes incubation, 5.5 pg of pilin adhere to 15,000 epithelial cells. When epithelial cells were preincubated with purified pilin, a subsequent decrease in adherence of labeled pilin was noted. It appears that pili mediate adherence ofPseudomonasorganism to human cornea.

ISSN:0271-3683    

DOI:10.3109/02713688209000772

出版商:Taylor&Francis    

年代:1982

数据来源: Taylor

摘要:

The development of the outer plexiform layer (OPL) at the posterior pole was studied in albino rats, ages 1 to 18 days. Light microscopic observations were consistent with previous reports that within the first postnatal week neuro-epithelial cells migrate into outer and inner nuclear layers with formation of the intervening OPL. The relation of neural and glial cells was consistent with the suggestion of others that guidance by glial cells influences the radial organization of the developing neural retina. The new observations presented in this paper raise the possibility that the horizontal orientation of neural processes in the outer plexiform layer depends upon guidance of glial cells.

ISSN:0271-3683    

DOI:10.3109/02713688209000773

出版商:Taylor&Francis    

年代:1982

数据来源: Taylor

摘要:

Proteins in tears are known to be highly heterogeneous. We have tried to take into consideration some of the difficulties encountered in studying tear proteins such as tear collection, the choice of the parameters to be studied, the adequacy of techniques for small sample volumes, etc. Levels of total tear proteins were determined in 101 samples and the electrophoreses were performed. On gel slabs, four major proteins were always found to be present : lactoferrin, lysozyme and two tear specific proteins. Concentrations of some individual proteins, lactoferrin, lysozyme, IgA, IgG and albumin were determined. Comparisons of lactoferrin and lysozyme contents were found to be more reliable when based on total protein rather than on their own concentrations as such.

ISSN:0271-3683    

DOI:10.3109/02713688209000774

出版商:Taylor&Francis    

年代:1982

数据来源: Taylor

摘要:

The effect of tryptophan and three major metabolites of tryptophan on the rabbit lens electrolyte balance was examined. Even at 3×10−3M tryptophan, tryptamine and xanthurenic acid had no effect on lens sodium, potassium and calcium content after a 20 hr incubation. Small but significant changes in lens sodium and potassium content were induced by 20 hr incubation in 2×10−3M 3-hydroxy-DL-kynurenine and 10−3M hydroxyanthranilic acid. Lens Na,K-ATPase activity was unaffected by 3×10−3M tryptophan. Tryptamine reduced, to a small extent, Na,K-ATPase activity at 3×10−3M, but was without effect at 10−3M. 3-hydroxy-DL-kynurenine (2×10−3M) and 3-hydroxyanthranilic acid (10−3M) inhibited Na,K-ATPase activity by 27% and 30% respectively. Only 3-hydroxy-DL-kynurenine had a demonstrable effect on86Rb uptake.It is concluded that, in contrast to findings in the amphibian lens, metabolites of tryptophan have minimal or no detrimental effects upon rabbit lens electrolyte balance under thein vitroconditions of these experiments. However, this does not rule out a long term effect of these compounds should they accumulate in the lens.

ISSN:0271-3683    

DOI:10.3109/02713688209000775

出版商:Taylor&Francis    

年代:1982

数据来源: Taylor

摘要:

The suitability of water proton spin-lattice relaxation time T1as a measure of corneal dysfunction is investigated in this paper. Proton nuclear magnetic resonance measurements were performed on excised rabbit corneas using the saturation recovery method to determine the proton spin-lattice relaxation time T1. Both freshly excised and progressively swollen rabbit corneas were studied. The experimental results are consistent with a two compartment model of“bound”water and“free”water. This model results in a linear correlation between 1 / T1(measured) and 1/corneal hydration. This correlation suggests that water proton T1values can be used as an index of corneal dysfunction.

ISSN:0271-3683    

DOI:10.3109/02713688209000776

出版商:Taylor&Francis    

年代:1982

数据来源: Taylor

摘要:

Focused ultrasound concentrates a large amount of ultrasonic energy into a small focal zone. We have used new techniques to develop a transducer that creates intracorneal, thermally induced lesions in rabbit eyesin vitro.' Histologic study shows that these lesions are confined to the stroma and that the procedure causes no structural damage to the corneal epithelium or endothelium or other ocular structures. The potential uses of this device in corneal research and therapy are discussed.

ISSN:0271-3683    

DOI:10.3109/02713688209000777

出版商:Taylor&Francis    

年代:1982

数据来源: Taylor

摘要:

Na/K ATPase activity has been determined in normal and cataractous human lenses using labeled ATP as a substrate. The enzyme is distributed throughout the lens with approximately 1/3 of the total activity in the capsule-epithelium and 1/2 of the activity in the cortex. Furthermore, the activity of Na/K ATPase decreases with increasing age and this decrease occurs primarily in the inner nuclear region. In severe cataractous lenses, a marked decrease in the Na/K ATPase activity has been demonstrated in all parts of the lens, in contrast to immature cataracts, where the decrease in the enzyme activity occurs primarily in the cortical and nuclear regions. A report of this investigation was presented at the 1931 ARVD meeting in Sarasota, Florida.

ISSN:0271-3683    

DOI:10.3109/02713688209000778

出版商:Taylor&Francis    

年代:1982

数据来源: Taylor

摘要:

Eyes of young New Zealand white rabbits were irradiated with 2000 rads of gamma radiation (60Co) and the eyes removed at 2, 8, 16, and 30 days post-irradiation for electron microscopic analysis. Lenses were treated histochemically for acid phos-phatase localization to examine the role of lyso-somal enzymes in the early development of radiation cataracts. Progressive degenerative morphological changes due to radiation included pronounced nuclear degeneration and cellular shrinkage within the germinative and pregerminative epithelium and severe swelling of superficial portions of lens fibers beneath these epithelial zones. Less dramatic changes occurred elsewhere in the superficial portions of the anterior and marginal lens segments. The epithelium of both irradiated and non-irradiated lenses contained small (60-70 nm) vesicles fused with the apical and lateral cellular borders. Irradiated lenses showed a 30-40% increase in population of these vesicles at all time intervals in the central (including the pregerminative) epithelium.Intercellularly located acid phosphatase reaction product, noted in the epithelium and subjacent cortex, was more prevalent after irradiation, especially in central and transitional epithelial zones. In the central zone the small vesicles typically were most numerous in areas of extensive intercellular reaction product. The occurrence of discrete packets of reaction product within the vesicles and the adjoining intercellular space, plus the resemblance of the peripheral vesicles to small Golgi vesicles also containing reaction product, suggested an exocytotic release of the enzyme. These appearances suggest that lysosomal hydrolases are released extracellularly by a secretory mechanism accelerated by radiation and that these hydrolases may play a role in both physiological and pathological functions of the lens.

ISSN:0271-3683    

DOI:10.3109/02713688209000779

出版商:Taylor&Francis    

年代:1982

数据来源: Taylor

摘要:

The effects of a potent aldose reductase inhibitor, ICI 105552, (l-(3,4-dichloro-benzyl)-3-methyl-1,2-dihydro-2-oxoquinol-4-ylacetic acid), upon the development of cataract in streptozotocin-diabetic rats were followed for 11 months. Daily intubation with ICI 105552 at 50 mg/kg body weight delayed the onset and rate of development of cataract considerably. The time taken for 50% of eyes to show cataract more severe than a few small punctate opacities exceeded 320 days, at least 170 days longer than in placebo-dosed diabetics. Only 4 eyes of inhibitor-dosed rats developed complete cataract as assessedin vivo; dissectionpost mortemshowed these lenses to be less degenerated than those of placebo-dosed diabetics. At day 149, progression of cataract beyond traces of opacity had occurred in all placebo-dosed diabetics. In certain diabetics dosed with ICI 105552 such progression did not occur even after 324 days of treatment. Intra-ocular haemorrhage developed in 8 of 14 eyes of placebo-dosed diabetics surviving 245 treatment days but was never evident in ICI 105552-dosed diabetics. ICI 105552 may therefore be suitable for long-term studies of the pathogenesis of certain complications secondary to diabetes.

ISSN:0271-3683    

DOI:10.3109/02713688209000780

出版商:Taylor&Francis    

年代:1982

数据来源: Taylor