Central modulatory neurons control fuel selection in flight muscle of migratory locust.
J Neurosci
; 23(4): 1109-13, 2003 Feb 15.
Article
in En
| MEDLINE
| ID: mdl-12598597
ABSTRACT
Insect flight is one of the most intense and energy-demanding physiological activities. High carbohydrate oxidation rates are necessary for take-off, but, to spare the limited carbohydrate reserves, long-distance flyers, such as locusts, soon switch to lipid as the main fuel. We demonstrate that before a flight, locust muscles are metabolically poised for take-off by the release of octopamine from central modulatory dorsal unpaired median (DUM) neurons, which increases the levels of the potent glycolytic activator fructose 2,6-bisphosphate in flight muscle. Because DUM neurons innervating the flight muscles are active during rest but selectively inhibited during flight, they stimulate carbohydrate catabolism during take-off but tend to decrease muscle glycolysis during prolonged flight. cAMP-dependent protein kinase A is necessary but not sufficient for signal transduction, suggesting parallel control via a calcium-dependent pathway. Locust flight is the first reported instance of a direct and specific involvement of neuronal activity in the control of muscle glycolysis in working muscle during exercise.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Muscle, Skeletal
/
Flight, Animal
/
Grasshoppers
/
Neurons
Limits:
Animals
Language:
En
Journal:
J Neurosci
Year:
2003
Document type:
Article
Affiliation country:
Germany