Phosphorylated compounds in the head and thoracic tissues of the adult housefly, Musca domestica L., during flight, rest, anoxia and starvation

Abstract

The presence of a -glycerophosphate representing some 20% of the total soluble P of the thoracic tissues of the resting intact adult housefly has been confirmed enzymically. The transition from cyclopropane-induced rest to normal activity was associated with a fall in thoracic [alpha]-glycerophosphate. A further fall on the assumption of full flight was not apparent but the level of inorganic phosphate rose significantly. Anoxia due to drowning caused an accumulation of thoracic [alpha]-glycerophosphate and a slower breakdown of adenosine triphosphate with the formation of inorganic phosphate and possibly adenosine monophosphate. Starvation to the point of prostration caused a fall in head adenosine triphosphate which could be reversed by injection of aqueous glucose. Extended cyclopropane anaesthesia, injected water or acetone were apparently without effect on P distribution. Changes in head and thoracic P compounds could occur independently in the same insect.