Cyclic AMP and glycerol concentrations in freeze-clamped human omental and subcutaneous adipose tissues.
OBJECTIVE
To compare intracellular concentrations of cyclic AMP, GTP, ATP, AMP and glycerol in omental and abdominal subcutaneous adipose tissues.


METHODS
Samples of omental and/or abdominal subcutaneous adipose tissues of 14 women undergoing elective surgery were freeze-clamped, deproteinized with perchloric acid and neutralized. All subjects were obese since it was not possible to freeze-clamp lean individuals.


METHODS
The concentrations of ATP and GTP were determined by ion-paired high performance liquid chromatography and AMP and glycerol enzymatically. Cyclic AMP was determined by radioimmunoassay. Intracellular nucleotide concentrations were calculated from tissue weights, water contents and relative amounts of sodium and potassium.


RESULTS
The intracellular concentration of cyclic AMP in omental adipose tissue (31 mumol/l) was twice as high as that in subcutaneous fat while those of ATP, GTP and AMP were similar at the two sites. Glycerol concentrations were higher in subcutaneous (472 mumol/l) than in omental (325 mumol/l) adipose tissue.


CONCLUSIONS
The results suggest higher relative stimulation of lipolysis by cyclic AMP in omental adipose tissue than in the subcutaneous region in situ. However, probably because of differences in blood flow and possibly in the lipolytic machinery, this is not reflected as a higher glycerol concentration.
Vikman
H L
HL
Department of Molecular and Cellular Physiology, PennState University College of Medicine, Hershey, USA.
Hreniuk
S P
SP
Kauffman
G F
GF
LaNoue
K F
KF
Martin
L F
LF
Ohisalo
J J
JJ
D000249:Adenosine Monophosphate / Q000032:analysis; D000255:Adenosine Triphosphate / Q000032:analysis; D000273:Adipose Tissue / Q000737:chemistry* / Q000166:cytology / Q000378:metabolism; D000328:Adult; D000242:Cyclic AMP / Q000032:analysis* / Q000378:metabolism; D005260:Female; D005990:Glycerol / Q000032:analysis* / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000032:analysis; D006801:Humans; D008875:Middle Aged; D009852:Omentum; D011188:Potassium / Q000032:analysis; D011863:Radioimmunoassay; D012964:Sodium / Q000032:analysis
D000249:Adenosine Monophosphate; D006160:Guanosine Triphosphate; D000255:Adenosine Triphosphate; D012964:Sodium; D000242:Cyclic AMP; D005990:Glycerol; D011188:Potassium