Medical Journal of the Islamic Republic Of Iran
مجله پزشکی جمهوری اسلامی ایران
Med J Islam Repub Iran
Medical Sciences
http://mjiri.iums.ac.ir
2
journal2
1016-1430
2251-6840
8
10.18869/mjiri
14
8888
13
en
jalali
1380
11
1
gregorian
2002
2
1
15
4
online
1
fulltext
en
HEPATOMA McARDLE-RH7777 CELLS HAVE THE SAME RESPONSE AS NORMAL RAT HEPATOCYTES TO BOTH DIBUTYRYL-cAMP AND ANTICALMODULINW-7
Biological Sciences
Biological Sciences
Original Research: Basic Science in Medicine
Original Research: Basic Science in Medicine
The effects of cAMP-analogue dibutyryl-cAMP and anticalmodulin W-7 were
studied on de novo synthesis and secretion of lipids in cultures of hepatoma McArdle
RH7777 cells and normal rat hepatocytes. Dibutyryl-cAMP and W -7 separately
caused a significant decrease in the secretion of de novo synthesized triacyl
[3H]glycerol in both cultures of McArdle cells and rat hepatocytes. The inhibitory
effects of dibutyryl-cAMP and W-7 were concentration-dependent and appeared
at the lowest concentration examined, 5JlM and 20JlM respectively. DibutyrylcAMP
at a concentration of 50 JlM and W -7 (20 µM) suppressed the secretion of
triacylglycerol by approx. 38% (p<0.05) and 37% (p<0.05) respectively. Dibutyryl.cAMP
but not W -7 also suppressed the secretion of phosphatidylcholine significantly.
Dibutyryl-cAMP and W-7 had no significant effect upon [3H]glycerollabeled
de novo formed triacylglycerol and phosphatidylcholine, except at the
highest concentration tested, 500JlM and 50JlM respectively, where both
triacylglycerol and phosphatidylcholine synthesis were suppressed significantly.
Similar findings were obtained on cultured hepatocytes.
The molar ratios of newly made triacylglycerol/phosphatidyl choline in the
media and cells of hepatocytes were about four times compared to that of McArdle
cells, indicating more lipidation and core expansion of nascent lipoprotein particles
in hepatocytes. The molar ratio of triacylglycerol/phosphatidyl choline in
the medium and cells of cultured McArdle cells was unchanged significantly i n
the presence of either dibutyryl-cAMP or W-7. However, the molar ratio was
decreased 25% (p<O.Ol) in the presence of dibutyryl-cAMP in the media but not
in the cells of cultured hepatocytes. These results suggest that hepatoma McArdle
cell's response to both cAMP-analogue and calmodulin antagonist are comparable
to that of normal rat hepatocytes. In addition, the inhibitory effects of
dibutyryl-cAMP and W-7 at low concentration are unlikely to be due to the suppression
oftriacylglycerol and phosphatidyl choline synthesis.
Calmodulin, Cyclic AMP, Hepatocyte, McArdle cells and VLDL
209
217
http://mjiri.iums.ac.ir/browse.php?a_code=A-10-298-240&slc_lang=en&sid=1
M
RASOULI
mehdi.rasouli@planetaccess.com
20031947532846004114
20031947532846004114
Yes
From the Department of Biochemistry and Lipid & Lipoprotein Research Group, University of Alberta, Edmonton, Canada T6H 2S2.
R
LEHNER
richard.lehner@ualbera.ca
20031947532846004115
20031947532846004115
No