Trehalose production in isolated fat body of the american cockroach, Periplaneta americana

Abstract

1. The trehalogenic capacity of incubating fat body tissue may be expressed in terms of the trehalogenic index (Trehalose produced during incubation/Trehalose produced + Glycogen remaining after incubation). 2. Pieces of fat body from the same individual have comparable trehalogenic indexes. 3. The trehalogenic index is relatively independent of pH flux in the incubating medium. 4. The trehalogenic index is elevated by calcium, but not by magnesium, whereas potassium ions tend to depress the trehalogenic index. 5. Aqueous extracts of corpora cardiaca, 10 −4 M octopamine and 10 −4M dopamine increase the trehalogenic index, whereas 10 −4 M tyramine causes the trehalogenic index to decrease.