Abstract
The different murine D2-type dopamine receptors (D(2L), D(2S), D(3L), D(3S), and D4) were expressed in Xenopus laevis oocytes. The D2-type receptors were all similarly and efficiently expressed in Xenopus oocytes and were shown to bind the D2 antagonist [125I]sulpride. They were all shown to activate Cl- influx upon agonist stimulation. Using the diagnostic inhibitor bumetanide, we were able to separate the Na+/K+/2Cl- cotransporter component of the Cl- influx from the total unidirectional Cl- influx. The D(3L) subtype was found to operate exclusively through the bumetanide-insensitive Cl- influx whereas the other D2-type receptors acted on the Na+/K+/2Cl- cotransporter as well. The pertussis toxin sensitivity of the receptor-activated chloride influx via the Na+/K+/2Cl- cotransporter varied between the various D2-type receptors showing that they may couple to different G proteins, and activate different second messenger systems.
Original language | English |
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Pages (from-to) | 191-195 |
Number of pages | 5 |
Journal | FEBS Letters |
Volume | 420 |
Issue number | 2-3 |
DOIs | |
State | Published - 29 Dec 1997 |
Externally published | Yes |
Bibliographical note
Funding Information:We thank Professors Chaim Garty from the Weizmann Institute and Yoram Oron from Tel Aviv University for helpful discussions and critical suggestions. We are grateful to Dr. Yael Loewenstein, The Hebrew University of Jerusalem, for providing oocytes for preliminary experiments. This work was supported by grants from the United States-Israel Binational Science Foundation, the Ernst and Anne Chain Research Programme, and the Leo and Julia Forchheimer Center for Molecular Genetics at the Weizmann Institute of Science (to S.F.). B.S.J. was the recipient of research fellowships from the Danish Natural Science Research Council, the Novo-Nordisk Foundation and the Danish Friends of the Weizmann Institute of Science.
Keywords
- Bumetanide
- Dopamine
- Murine D2 dopamine receptor (D, D, D)
- Na/K/2Cl cotransporter
- Xenopus oocyte