(1) Annulus fibrosus and nucleus pulposus of human intervertebral discs at different degrees of atherosclerosis were disintegrated by elastase. (2) The material disintegrated by elastase -- called elastolysate -- could be separated into hydrophobic (apolar) and hydrophilic (polar) peptides. Parallel with the degree of atherosclerosis the amount of hydrophobic peptides increased, whereas that of the hydrophilic peptides decreased. (3) In annulus fibrosus and nucleus pulposus two kinds of fluorescence maxima were measured. The one, A:F 350:405, is known as fluorescence maxima of elastin- and collagen-peptides. The other, A:F 410:470, is related to a similar substance called atherofluorescent component (AFC), which has been isolated before from the plaques of atherosclerotic aorta. This substance accumulates mainly in nucleus pulposus and resembles lipofuscin-like bodies. (4) These bodies show a positive reaction with thiobarbituric acid, giving a red coloration characteristic for malondialdehyde. In nucleus pulposus the amount of lipofuscin-like substances is much greater than in annulus fibrosus. (5) The hydrophilic peptides, although they show the same fluorescence maxima as the hydrophobic peptides, do not give any reaction with thiobarbituric acid. It is supposed that in these cases the cross-linked protein contains instead of malondialdehyde other reactive aldehydes.

Adolescent↗

PubMedDate not supplied

[Use of a manganese citrate complex in the determination of liver enzyme activities in the aging process and following treatment with aminoethylisothiuronium bromide hydrobromide (AET)].

Some oxidation enzyme as well as reductase and dehydrogenases in liver samples were estimated. With the manganese-citrate plus diethylen-p-phenylene-diamine complex method an increases reduction-capacity and succino-dehydrogenase activity was recorded in the liver samples of the 23 month old rat. No differences were found between the 6 and 12 month old rat liver samples. Following a 8-month amino-ethyl-isothiuronium. Br. HBr (AET) treatment (100 mg/kg) of mice both the reduction-capacity and the succino-dehydrogenase activity showed an elevated value in the liver samples of the experimental animals.

Aging↗