Abstract
The purpose of the present study was to assess the effects of 2-mercaptoacetate (MA),
an inhibitor of hepatic fatty acid oxidation, on the metabolic and pancreatic hormone
responses to a prolonged (3 h) swimming exercise. All rats were first adrenodemedullated
and were either submitted for 3 weeks to a normal (5% fat) or a medium-fat diet (MF;
18% fat). After being submitted to an exercise swimming habituation programme for
one week, rats under both dietary conditions were either injected with a bolus dose
of MA (600µmol/kg; ip) or with a saline solution. MA and saline injected rats were
either sacrificed after a 3-h swimming exercise or after a 3-h resting period. Administration
of MA was associated with a lower level of β-hydroxybutyrate after exercise in rats
fed the MF diet, higher resting and exercising blood glucose levels in rats fed the
MF diet, and higher resting and exercising levels of hepatic glycogen in rats fed
a normal diet. There were, however, no significant effects of MA on free fatty acid,
insulin, glucagon, epinephrine, and norepinephrine concentrations in both dietary
conditions either at rest or after exercise. Therefore, the present data do not provide
any evidence that the administration of MA, an inhibitor of hepatic fatty acid oxidation,
influences the pancreatic hormonal response to exercise. There was also no evidence
of a lowering effect of MA on blood glucose levels during exercise.
Key words
Insulin - liver regulation - fat diet
