Multiple pathways from three types of sugar receptor sites to metabotropic transduction pathways of the blowfly: Study by the whole cell-clamp experiments

• Published in: Comparative biochemistry and physiology. Part A, Molecular & integrative physiology Molecular & integrative physiology, 2011-09, Vol.160 (1), p.94-99
• Main Authors: Kan, Hideko, Kataoka-Shirasugi, Naoko, Amakawa, Taisaku
• Format: Article
• Language: English
• Subjects: adenylate cyclase; Adenylyl Cyclase Inhibitors; adults; Aminoquinolines - pharmacology; Animals; Calliphoridae; Chemoreceptor Cells - cytology; Chemoreceptor Cells - drug effects; Chemoreceptor Cells - physiology; cyclic AMP; Cyclic AMP - physiology; cyclic GMP; Cyclic GMP - physiology; Dideoxyadenosine - analogs & derivatives; Dideoxyadenosine - pharmacology; Diptera - drug effects; Diptera - physiology; Estrenes - pharmacology; Fly; fructose; Fructose - pharmacology; guanylate cyclase; Guanylate Cyclase - antagonists & inhibitors; Metabotropic; Multiple; Neuron; neurons; Patch-Clamp Techniques; Phormia regina; phospholipase C; Pyrrolidinones - pharmacology; Receptor site; Signal Transduction; sucrose; Sucrose - pharmacology; Taste; Taste - physiology; Transduction; Type C Phospholipases - antagonists & inhibitors; valine; Valine - pharmacology; Whole cell-clamp
• ISSN: 1095-6433; 1531-4332
• DOI: 10.1016/j.cbpa.2011.05.010

Multiple pathways from three types of multiple receptor sites to three types of metabotropic signal transduction pathways were investigated in the whole cell-clamp experiments using isolated labellar sugar receptor neurons (cells) of the adult blowfly, Phormia regina. First, the concentration–response curves of three types of sweet taste components specialized to multiple receptor sites were obtained: sucrose for the pyranose sites (P-sites), fructose for the furanose sites (F-sites), and l-valine for the alkyl sites (R-sites). Next, the effects of inhibitors such as 2′, 5′-dideoxyadenosine on adenylyl cyclase in the cAMP pathway, LY 83583 on guanylyl cyclase in the cGMP pathway, and U-73122 on phospholipase C in the IP 3 pathway were examined. The results showed that all of the inhibitors affected each specific target in the second-messenger transduction pathways. The obtained results verified that the P-site corresponded to the cAMP, the F-site to the cGMP, and the R-site to the IP 3 transduction pathway, and that these three signal pathways did not have crossing points.