Allatostatin-like immunoreactivity in the abdomen of the locust Schistocerca gregaria

Abstract

A polyclonal antibody against allatostatin 1 (AST-1) of cockroach Diploptera punctata was used to investigate the distribution of AST-like immunoreactivity within the abdomen of the locust, Schistocerca gregaria. In the abdominal ganglia, AST-like immunoreactivity was found in both cell bodies and neuropile. In ganglia 6 and 7, staining was found in serial homologous cell bodies in anterior dorsolateral and dorsomedial, and posterior ventrolateral and ventromedial locations. In the terminal ganglion, the numerous immunoreactive somata were smaller in size than those in the unfused ganglia. The combination of backfill experiments with immunocytochemistry showed that, in abdominal ganglion 7, one neuron of the ventromedian cell body cluster and two of the ventrolateral cluster innervated the oviduct, which itself was covered with a dense mesh of AST-immunoreactive varicosities. Combining electron microscopy with immunohistochemistry revealed AST-like immunoreactivity in dense-core vesicles located in neurohaemal-like terminals lacking structures normally found in synapses. A mesh of AST-immunoreactive varicosities was also found on the muscles of the spermatheca and the spermathecal duct. In addition, a mesh of strongly stained varicosities was present in the distal perisympathetic organs (neurohaemal organs in the abdomen) and on the lateral heart nerves (a putative neurohaemal release zone). These data indicate that AST is an important neuroactive substance that is probably involved in multiple tasks in the control of the locust abdomen.

Allatostatin A-like immunoreactivity in the nervous system and gut of the larval midge, Chironomus riparius (Meigen): Modulation of hindgut motility, rectal K+ transport and implications for exposure to salinity

“…The processes in the ganglia are likely to originate from the neurons in the brain, suggesting that allatostatins act as neurotransmitters relaying information from the brain to other neurons in the ganglia of the ventral nerve cord in larval C. riparius. Similar processes have been found in other insects (Skiebe et al, 2006;Žitňan et al, 1993). At least one of the two pairs of lateral neurons in the terminal ganglion give rise to processes that innervate the hindgut (see Fig.…”

“…The Journal of Experimental Biology (2014) Allatostatin immunoreactivity has been well documented in the nervous systems of insects with AST-IR cell bodies routinely found in the brain and abdominal ganglia (Skiebe et al, 2006;Žitňan et al, 1993;Kreissl et al, 1999;Lange et al, 1993;Hernández-Martínez et al, 2005). In C. riparius larvae, the brain contains at least five paired AST-IR cell bodies at the anterior edge of the frontal lobes (Fig.…”

Structural and Molecular Properties of Insect Type II Motor Axon Terminals

“…For locusts, the same fixation was used as mentioned in the previous chapter. For Drosophila we used fixation in 1% GA + 2% PFA in 0.1 M PBS (pH 7.4) for 3 h at RT; after washing in dH 2 O (3 × 5 min) specimen were post-fixed in 1% OsO 4 in the same buffer for 1 h; rinsed again and dehydrated in ascending ethanol series, 30% 50%, 70%, 2 × 10 min, on a rotor, 96%, 100%, 2 × 15 min; then specimen were impregnated with resin LRWhite I, 4 h and RWhite II, 3 h, on a rotor at RT and polymerized in fresh LRWhite in gelatin capsules at 58°C for 24 h. The fixation protocol of tissue of adult locusts (Schistocerca gregaria) for immunogold-staining was described in Skiebe et al ( 2006 ).…”

Multiple modulators act on the cardiac ganglion of the crab,Cancer borealis

“…The allatostatins (ASTs) consist of a family of peptides present in various insects including cockroaches (Ding et al, 1995;Vilaplana et al, 1999), moths (Audsley and Weaver, 2003;Kramer et al, 1991), locusts (Skiebe et al, 2006;Veelaert et al, 1996a;Veelaert et al, 1996b), mosquitoes (HernandezMartinez et al, 2005) and flies (Duve et al, 1993;Lenz et al, 2001;Williamson et al, 2001). In crustaceans, including C. borealis, AST-like immunoreactivity has been detected in the POs and other structures (Christie et al, 1995;Kilman et al, 1999;Pulver and Marder, 2002;Skiebe, 1999;Skiebe, 2001;Skiebe and Schneider, 1994;Yasuda-Kamatani and Yasuda, 2006).…”