Differential induction of inositol phosphate metabolism by three adipokinetic hormones

Knockdown of the Adipokinetic Hormone Receptor Increases Feeding Frequency in the Two-Spotted Cricket Gryllus bimaculatus

“…In L. migratoria, AKH activates the intracellular production of cAMP (6). By contrast, inositol 1,4,5-trisphosphate is also a possible second messenger mediating AKH stimulation in Pachnoda sinuata and L. migratoria (18,19).…”

Endocrine control of TAG lipase in the fat body of the migratory locust, Locusta migratoria

“…2B) 60 min after injection of analogues of IP 3 and cAMP. These two compounds are known to be involved in the activation of glycogen phosphorylase in locusts (Vroemen et al 1995(Vroemen et al , 1997. For comparison, the activation state of glycogen phosphorylase was measured 15 min after injection of the respective second messengers using a different group of locusts (Fig.…”

“…2C). The second messenger IP 3 , which also accumulates upon action of Locmi-AKH peptides (Vroemen et al 1997), does not display such a dual function. Whereas injection of the analog F-IP 3 activates glycogen phosphorylase, the same dose of F-IP 3 fails to activate the TAG lipase in locust fat body (Fig.…”

“…Levels of cAMP reach their (Vroemen et al, 1995), and IP 3 (Vroemen et al, 1997) in the fat body and octopamine in the haemolymph (Goosey and Candy, 1980); (B) activation of the key enzymes: TAG lipase (this study) and glycogen phosphorylase (Ga¨de, 1981); (C) concentrations of diacylglycerol and trehalose in the haemolymph (Beenakkers et al, 1981). maximum after 1 min (Vroemen et al 1995) and concentrations of IP 3 peak after 5 min (Vroemen et al 1997) upon injection of the three Locmi-AKHs (see also Fig. 4).…”

“…Trehalose released from the fat body does not accumulate in the haemolymph, probably because consumption and mobilization are balanced. The carbohydrate concentration in the haemolymph is, therefore, not useful for observing the hypertrehalosaemic effect (see Ga¨de and Auerswald 2003) but the activation of glycogen phosphorylase in the fat body of locust has been extensively studied (see, for example, Ga¨de 1981;Vroemen et al 1995Vroemen et al , 1997. Only scattered information, however, is available on the action of TAG lipase in the fat body of insects in general.…”