EUROPEAN JOURNAL OF ENTOMOLOGY

Eur. J. Entomol. 94 (3): 385-391, 1997

Lipid synthesis by ovaries and fat body of Aedes aegypti (Diptera: Culicidae)

ZIEGLER R.

N/A

Synthesis of fatty acids by the ovaries of Aedes aegypti was demonstrated by incubating ovaries in tritiated water. Mostly phospholipids were synthesized, however, in mature oocytes the vast majority of lipids are triacylglycerol. 80% of the fatty acids synthesized in vitro were saturated while in the mature oocytes 70% of the fatty acids are unsaturated. These results suggest that lipids synthesized in the oocytes contribute only a minor portion of the lipid complement of the egg and that most of the oocyte lipids are taken up from external sources. The amount of lipid synthesized in vitro by the ovaries was extremely small, less than 1/1000 of the amount of lipid that accumulates in the oocytes. This result, however, may have been influenced by the in vitro conditions. Fat body, under the same conditions, synthesized less than 1/100 of the amount synthesized in vivo. The rate of lipid synthesis in this in vitro system was low, however, the regulation of lipid synthesis appeared to function. Lipid synthesis in ovaries and fat body was strongly inhibited by Tabanus adipokinetic hormone, whereas four other peptides isolated from A. aegypti did not influence lipid synthesis. In the fat body of sugar-fed mosquitoes, lipid synthesis was twice as great as in blood-fed animals.

Keywords: Lipid synthesis, Aedes aegypti, mosquito, oocytes, fat body, Tabanus adipokinetic hormone 

Accepted: April 25, 1997; Published: July 30, 1997  Show citation