The effect of hypertension on lysosomal enzyme activities in aortic endothelial cells

Sasahara, Masakiyo; Hayase, Yoneko; Kawai, Jun; Yukioka, Naoya; Hazama, Fumitada

doi:10.1536/ihj.29.518

Cited by 1 publication

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, it has been shown previously that lysosomal releasates from human polymorphonuclear leukocytes, when injected intradermally in rabbits, induce severe microvascular injury with disruption of the vessel's basement membrane, platelet accumulation and microthrombosis (47). Moreover, lysosomal enzymes may participate in the process of atherogenesis by contributing to the injury to the arterial wall (48,49) and the increase of serum Hex in some clinical conditions has been related to the development of atherosclerotic complications (50). Glycoproteins, glycosaminoglycans and glycolipids are present both on the surface of endothelial cells and platelets and in the extracellular matrix and their partial degradation by platelet-released acid hydro-lases might well contribute to the regulation of thrombus formation as well as to the remodelling of extracellular matrix.…”

Section: Discussionmentioning

confidence: 99%

Platelets Release their Lysosomal Content In Vivo in Humans upon Activation

Ciferri

Emiliani²,

Guglielmini³

et al. 2000

Thromb Haemost

View full text Add to dashboard Cite

SummaryPlatelets contain, besides α- and δ-granules, lysosomes which store glycohydrolases able to degrade glycoproteins, glycolipids and glycosaminoglycans. While several studies have shown that α- and δ-granule secretion takes place “in vivo” in humans upon platelet activation, no data are available on the “in vivo” release of lysosomes. We have studied the release of platelet lysosomal contents “in vivo” in healthy volunteers at a localized site of platelet activation by measuring markers of lysosomal secretion in the blood oozing from a skin wound inflicted for the measurement of the bleeding-time. The levels of β-N-acetylhexosaminidase (Hex) were 13.1 ± 0.85 mU/ml in bleedingtime blood and 10.2 ± 0.66 mU/ml in plasma (p <0.001). Hex in serum was 16.4 ± 0.72 mU/ml. The levels of β-galactosidase were also higher in bleeding-time blood than in plasma (0.85 ± 0.07 mU/ml vs 0.4 ± 0.05 mU/ml, p <0.001). In bleeding-time blood collected at one minute intervals, Hex rose progressively consistent with ongoing platelet activation and flow-cytometry showed a progressive increase of the expression of LIMP and LAMP-2, two lysosomal associated proteins. In conclusion, our data demonstrate that platelet lysosomal glycohydrolases are released “in vivo” in humans upon platelet activation.

show abstract

Section: Discussionmentioning

confidence: 99%