Reduced dimerization of lipoprotein lipase in post-heparin plasma of a patient with hyperchylomicronemia.
Biochim Biophys Acta
; 1254(1): 30-6, 1995 Jan 03.
Article
in En
| MEDLINE
| ID: mdl-7811743
ABSTRACT
As in post-heparin plasma of control subjects, post-heparin plasma of a patient with hyperchylomicronemia contained lipoprotein lipase (LPL) subunits with M(r) = 57,000. But although the amount of LPL was the same as in post-heparin plasma of controls, no LPL activity was detectable. Nearly all the LPL in post-heparin plasma of controls bound to heparin-Sepharose and this LPL bound was mainly eluted with 1.5 M NaCl in parallel with the activity. In post-heparin plasma of the patient, 58% of the LPL subunits did not bind to heparin-Sepharose and 23% was eluted with 0.6 M NaCl. Studies by sucrose density gradient centrifugation showed that almost all the LPL in post-heparin plasma of controls was recovered in the peak with a sedimentation coefficient of 6.8 S, corresponding to the position of a dimeric form of LPL, in parallel with the activity; little LPL was recovered in the peak with a sedimentation coefficient of 4.0 S, corresponding to the position of a monomeric form of LPL. In post-heparin plasma of the patient, 35% of the LPL subunits was recovered in fractions with larger sedimentation coefficients at the bottom of the centrifuge tube, indicating the presence of an aggregated form(s) of LPL; the amount of the monomeric form of LPL was increased, while that of the dimeric form was decreased. Thus, defect of LPL activity in post-heparin plasma of the patient with hyperchylomicronemia could result from reduced dimerization of LPL subunits.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Lipoprotein Lipase
/
Hyperlipoproteinemia Type I
Limits:
Adolescent
/
Female
/
Humans
Language:
En
Journal:
Biochim Biophys Acta
Year:
1995
Document type:
Article
Affiliation country:
Japan