Skip to main content
. 2000 Feb 15;97(4):1829–1834. doi: 10.1073/pnas.97.4.1829

Figure 2.

Figure 2

Coupling specificity of Ap oa1. (A) Dose-response curve of agonists of Ap oa1 on cAMP production in a HEK 293 cell line stably expressing Ap oa1. Neurotransmitters, OA, tyramine, and dopamine are tested at various concentrations in the presence of 500 μM 3-isobutyl-1-methylxanthine. Data are expressed as percentage of maximum response of cAMP production. (B) Dose-response curve of production of inositol phosphates (IPs) by Ap oa1 with OA (filled circle) and by cardiac m3 mAChR with acetylcholine (open circle) in HEK 293 cells heterologously expressing the receptors. Data are expressed as percentage of maximum response of IPs production. (C) The coupling specificity of Ap oa1 examined in Xenopus oocyte. Current tracings from three representative oocytes of voltage-clamp experiments. Either Ap oa1 or β2-adrenergic receptor cRNA (2.5 ng) were coinjected into oocytes with 5 ng CFTR cRNA and 0.1 ng mouse 5-HT2c cRNA. Lym oa1 (2.5 ng) cRNA was also coinjected with 5 ng CFTR cRNA. OA (100 nM), 100 nM 5-HT, and 1 μM isoproterenol (ISO) were used to induce currents from each oocyte. OA (1 μM) was used in stimulating Lym oa1 (EC50 = ≈5 μM). Drugs were applied to the bath solution (arrows) for 30 s and washed out. Holding potential was −60 mV.