Expression of Two Different Cholecystokinin Receptors in Xenopus Oocytes Injected with mRNA from Rabbit Pancreas and Rat Hippocampus.

• Shigeri Yasushi

  Present address: Department of Organic Materials, Osaka National Research Institute, Agency of Industrial Science and Technology, Ministry of International Trade and Industry

• Shinohara Shunji

  Discovery Research Laboratories II. Shionogi and Co., Ltd.

• Murata Shunji

  Discovery Research Laboratories II. Shionogi and Co., Ltd.

• Fujimoto Masafumi

  Shionogi Research Laboratories, Shionogi and Co., Ltd.

• Kawasaki Kazuo

  Discovery Research Laboratories II. Shionogi and Co., Ltd.

Bibliographic Information

Other Title

• Expression of Two Different Cholecystokinin Receptors in Xenopus Oocytes Injected with mRNA from Rabbit Pancreas ana Rat Hippocampus

Abstract

Electrophysiological responses to cholecystokinin (CCK) were studied in Xenopus oocyies injected with mRNA from rabbit pancreas or rat hippocampus. CCK-octapeptide(26-33) (sulfated form) (CCK-8) elicited inward currents in both groups. In oocyies injected with pancreatic mRNA, CCK-8-induced currents were composed of two components, fast and slow. However, in oocytes injected with hippocampal mRNA, fast currents disappeared. The potency ranking of the agonists and the antagonist indicated that the receptors expressed by pancreatic and hippocampal mRNA were CCK_A-and CCK_B-subtypes, respectively. Extracellular application of EGTA had little effect on the CCK_B-mediated response, but attenuated the CCK_A-mediated one. Intracellular injection of EGTA abolished the CCK_B-mediated response, whereas small smooth currents remained in oocyies expressing the CCK_A-receptor. The reversal potentials of the CCK_A-and CCK_B-receptor-mediated responses were consistent with that for Cl^- currents. However, the reversal potential of the small smooth currents in EGTA-loaded oocytes expressing the CCK_A-receptors was close to that for a non-selective cation channel. These results suggest that CCK-8 activates at least two different channels, a Ca²⁺-dependent Cl^- channel and a non-selective cation channel in oocytes expressing the CCK_A-receptor, while the CCK_B-receptor elicits only a Ca²⁺-dependent Cl^- channel.

Journal

• The Japanese Journal of Pharmacology

  The Japanese Journal of Pharmacology 72 (1), 9-15, 1996

  The Japanese Pharmacological Society

Keywords

• Cholecystokinin (CCK)
• <I>Xenopus</I> oocyte
• Electrophysiology
• CCK<SUB>A</SUB>-receptor
• CCK<SUB>B</SUB>-receptor

Details

• CRID: 1390001204286347136
• NII Article ID: 10008675507
• NII Book ID: AA00691188
• DOI: 10.1254/jjp.72.9
• COI: 1:CAS:528:DyaK28Xlsl2gurc%3D
• ISSN: 13473506
• ISSN: 00215198
• PubMed: 8902594
• Web Site: https://api.elsevier.com/content/article/PII:S002151981933940X?httpAccept=text/xml
• Web Site: https://api.elsevier.com/content/article/PII:S002151981933940X?httpAccept=text/plain
• Web Site: https://search.jamas.or.jp/link/ui/1997051191
• Text Lang: en
• Data Source:
  • JaLC
  • Crossref
  • PubMed
  • CiNii Articles
• Abstract License Flag: Disallowed