Zusammenfassung
Die Kataraktogenese des normalen, alternden Auges kann durch eine kontinuierliche Zunahme von Streulicht erklärt werden, das die alternde Linse abstrahlt. Diese Zunahme ist eine Exponentialfunktion des Alters, deren Zeitkonstante im Durchschnitt 35 Jahre beträgt. Ein entscheidender Faktor dieses Streulichtes ist die Kondensation von Molekülen zu Aggregaten. Aggregationszustände sind indessen auch die Hauptursache einer breiten Klasse von „Kondensationskrankheiten”, die die Spätfolgen des Diabetes mellitus, der Alzheimerschen Krankheit und anderen einschließen. Es wird hier eine vereinfachte Darstellung der Mechanismen dieser Krankheiten und eine daraus folgende Strategie zu deren Bekämpfung gegeben. Im Falle der menschlichen Katarakt müsste ein Inhibitor, um als wirksam zu gelten, im Durchschnitt die Zeitkonstante von etwa 20 % oder mehr vergrößern.
There are reasons to classify a number of apparently disparate diseases as “condensation” (or molecular aggregation) diseases. Examples of such condensation diseases include the late phase of diabetes mellitus, Alzheimer's disease and others. With an expanding knowledge, the list of these diseases is likely to increase. We shall describe the underlying common mechanisms, the aim being to find anticataractogenic drugs based on this insight. The common, most important denominator of various clinically differing condensation diseases derives from the interaction of the macromolecules which is in part attractive and in part repulsive. Aggregation resp. clumping of the macromolecules of the cristalline lens, the reasons for light scattering, may be prevented by introducing a number of molecules of various designs into the original macromolecular complex which reduce the tendency of aggregation. Cataract inhibitors of this category may be regarded as effective if they are able to increase the time constant of the normal aging process (i.e. the increment of scatter) by about 20 % .
Schlüsselwörter
Kataraktogenese - Makromoleküle - Streulichtmechanismen - Kältekatarakt
Key words
Cataractogenic mechanisms - cold cataract - macromolecules
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1 Herrn Prof. Dr. Balder Gloor gewidmet.
2 Manuskript eingereicht am 26. 7. 99 und in der vorliegenden Form angenommen.
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