Concentrations of Some Ribonucleotides, L‐lactate, and Pyruvate in Human Senile Cataractous Lenses With Special Reference to Anterior Capsular/Subcapsular Opacity

Self Cite

The results are reported of 38 ultrasonographic in vivo mensurations of intraindividual differences in axial thickness between a cataractous lens in one eye and a biomicroscopically clear or slightly cataractous lens (incipient deep cortical opacity) in the other. Obviously intumescent cataractous lenses were excluded. In general, the cataractous lens was thinner than the contralateral clear or slightly cataractous lens. Large decreases in lens thickness appeared in lenses with the capsule-near opacities of posterior subcapsular cataract (PSC) + anterior capsular/subcapsular opacity (ACSCO). PSC was more closely correlated to lens thinning than was ACSCO. Nuclear cataract very often occurred in thin lenses, but did not appear to cause lens thinning per se. Deep cortical opacity was not associated with lens thinning. The present results contributed to our argumentation that the decrease in lens thickness is due to a leak of lens material through the "lens membrane" beside a possible cessation of growth of the lens fibres.

Section: Methodsmentioning

confidence: 99%

“…Thus, ACSCO in human senile cataract has been found to be associated with a) low ribonucleotide pools (Bruun Laursen 1976), b) an increase in lens sodium ion concentration, and c) a fall in lens potassium ion concentration (Klauber R. Bruun Laursen 1977).…”

mentioning

confidence: 98%

Variations of Lens Thickness in Relation to Biomicroscopic Types of Human Senile Cataract

Laursen

Fledelius

1979

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“…Enzyme activity was determined in the anterior tissues of 30 and in the posterior structures of 4 cataractous lenses. Cataractous lenses were selected and classified as described by Bruun Laursen (1976). However, noradrenaline and phenylephrine were not avoided, and the patients were not fasted.…”

Section: Methodsmentioning

confidence: 99%

“…The aim of the present study was to examine a possible correlation between the Na-K ATP'ase activity in the anterior lens structures and the extent of the biomicroscopically visible anterior capsular/subcapsular opacity (AC SCO) (Bruun Laursen 1976), previously found to be an indicator of increasing C,,+/C,+ ratio in the lens water (Klauber & Bruun Laursen 1977). T h e study was carried out by a) investigating the histochemical location of ATP'ase reaction products in the anterior part of the lens, b) biochemical analysis of the enzyme activity in the anterior lens tissue and c) examining the influence of changes in the C,,+/C,+ ratio o n the activity of the enzyme system.…”

mentioning

confidence: 99%

HUMAN SENILE CATARACT AND Na‐K ATP'ase ACTIVITY IN THE ANTERIOR LENS STRUCTURES

Klauber

1980

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Location and in vitro determination of Na-K ATP'ase activity in the anterior structures of individual human lenses with senile cataract are reported, with special reference to anterior capsular/subcapsular opacity (ACSCO). Histochemically, ATP'ase reaction products were found exclusively in the epithelium. Even totally opaque lenses showed strong positive reactions. Biochemically, increasing ratios of Na+/K+ concentrations in the assay medium resulted in an increase in enzyme activity to a limited degree, whereafter the activity remained stable. We cannot decide whether the Na-K ATP'ase activity of the anterior lens structures is unchanged in relation to ACSCO as indicated by our figures. For there are methodological problems, although our analytical error, expressed as the variation coefficient for slaughterhouse pig lenses, seems to be one of the lowest so far reported in the literature on interindividual, non-pooled material.

“…The lenses were treated in accordance with the methods used by Laursen (1976), and the biochemical analyses of 1-lactate, pyruvate, RTP, RDP and AMP were carried out as described in Bergmeyer (1974) with modifications as described by Laursen (1976).…”

Section: Methodsmentioning

confidence: 99%

In Vitro Investigations on the Effect of Pilocarpine on the Metabolism in Pig Lenses Illustrated With Some Intermediate Metabolites

Klauber

1977

22 pairs of pig lenses were incubated in TCM 199 5 g, with pilocarpine 5 X 10(-4) M and 10(-2) M. 5 X 10(-4) M is the probable concentration in the aqueous during ordinary pilocarpine medication. The concentration of 1-lactate, pyruvate, RTP, RDP and AMP was determined in the lenses and the assimilation of glucose and the production of 1-lactate and pyruvate were measured. As far as pilocarpine 5 X 10(-4) M was concerned no significant differences were found, but pilocarpine 10(-2) M gave a significantly higher 1-lactate concentration in the lenses (118%) and increased the assimilation of glucose to 120% and also augmented the production of 1-lactate to 168% and the pyruvate to 184%, tending to show that pilocarpine 10(-2) M increased the glycolytic activity in the lenses. The concentrations of RTP, RDP and AMP were unchanged.