Blood flow and release of free fatty acids in the omentum, mesentery and subcutaneous adipose tissue of the dog in haemorrhagic shock
Kovách, A.G.; Rosell, S.; Sándor, P.; Hamar, J.; Ikrényi, K.; Kovách, E.
Acta Physiologica Academiae Scientiarum Hungaricae 45(1-2): 79-87
1974
ISSN/ISBN: 0001-6756 PMID: 4470857 Document Number: 81198
Blood flow, release of free fatty acids (FFA) and glycerol were measured in the subcutaneous, mesenteric and omental adipose tissues in chloralose-anesthetized dogs during a standardized hemorrhagic shock procedure. Resting blood flows were 6.3 .+-. 1.4 ml/min per 100 g (.+-. standard error of the mean) in the subcutis, 14.8 .+-. 33 ml/min per 100 g in the mesentery and 5.3 .+-. 1.2 ml/min per 100 g in the omentum. There was a pronounced reduction of blood flow during bleeding to an arterial pressure of 55 mm Hg for 90 min and it remained low during bleeding to 35 mm Hg for an additional 90 min period. Blood flow in the mesentery was significantly higher than in the other 2 adipose tissues in both the control and the bleeding periods. There was no increase of FFA release from adipose tissue but glycerol release from the mesentery was significantly increased. The arterial concentration of FFA did not change but there was a significant elevation of the glycerol concentration from 0.21 .+-. 0.04 mM to 0.95 .+-. 0.22 mM (P < 0.05). Arterial pH decreased from 7.28 .+-. 0.03 to 7.06 .+-. 0.04, and the lactate level rose from 3.18 .+-. 0.38 to 10.66 .+-. 1.61 mM during bleeding. The low blood flow in adipose tissue following bleeding may impair the outflow of FFA and glycerol. Regional differences in the intensity of the blood flow reduction may be the explanation for the significant rise in the outflow of glycerol from the mesentery but not from the subcutis or the omentum. The re-esterification of FFA increased following bleeding, presumably due to the high lactate concentration. As a consequence of the low pH, the lipolytic rate diminished in adipose tissue despite a presumably high sympathetic neurohumoral activity. The rise in the re-esterification rate and inhibition of lipolysis as well as the diminution in a adipose tissue blood flow counteracts the outflow of FFA.