HYPERTREHALOSEMIC FACTORS FROM THE CORPORA CARDIACA OF THE HONEYBEE (APIS-MELLIFERA) AND THE PAPER WASP (POLISTES EXCLAMANS)

Measuring the total carbohydrate concentration in the haemolymph (anth rone-positive material), heterologous injections of honeybee (Apis mel lifera) and paper wasp (Polistes exclamans) corpus cardiacum (CC) extr acts resulted in hyperglycemia in Periplaneta, but homologous injectio ns caused no increase in total blood carbohydrates. However, when indi vidual sugars like glucose, fructose and trehalose were quantified usi ng a high pressure liquid chromatography method, then homologous injec tions of CC extracts showed a distinct hypertrehalosemic effect in bot h hymenopteran species. There was no effect of the extracts on glucose or fructose titers. The decrease of glucose, fructose and trehalose t iters during the time between taking blood samples in honeybees (becau se of starvation) had to be carefully monitored in order to detect the hypertrehalosemic effect of the extracts. Trehalose titers in unfed w asps on the other hand did not diminish during the time between blood sampling. In spite of large lipid stores in the fat body and a high bl ood lipid titer (15 mg/ml) in Polistes, there was a complete lack of h yperlipemic response to homologous injections of CC extracts. There wa s also no evidence of proline utilization as an energy source in eithe r species.