Selective coupling with K+ currents of muscarinic acetylcholine receptor subtypes in NG108-15 cells

Abstract

The primary structures of two muscarinic acetylcholine receptor (mAChR) species, designated as mAChR I and mAChR II, have been elucidated by cloning and sequence analysis of DNAs complementary to the porcine cerebral and cardiac messenger RNAs, respectively. mAChR I and mAChR II expressed in Xenopus oocytes differ from each other both in acetylcholine-induced response and in antagonist binding properties. These results, together with the differential tissue location of the two mAChR mRNAs, have indicated that pharmacologically distinguishable subtypes of the mAChR represent distinct gene products. The primary structures of two additional mammalian mAChR species, designated as mAChR III and mAChR IV, have subsequently been deduced from the nucleotide sequences of the cloned cDNAs or genomic DNAs. We report here that mAChR I and mAChR III expressed in NG108-15 neuroblastoma-glioma hybrid cells, but not mAChR II and mAChR IV, efficiently mediate phosphoinositide hydrolysis, activation of a Ca2+-dependent K+ current and inhibition of the M-current, a voltage-dependent K+ current sensitive to muscarinic agonists.

Streptozotocin, an inducer of NAD+ decrease, attenuates M‐potassium current inhibition by ATP, bradykinin, angiotensin II, endothelin 1 and acetylcholine in NG108‐15 cells

“…Bath perfusion with the maximum dose of five different agonists (100/IM ATE 10 nM bradykinin, 100 nM angiotensin II, 100 nM endothelin 1 and 10]tM ACh) of NGPM1-27 cells, voltage-clamped at a depolarized membrane potential of -20 mV, produced a steady inward current ranging from 0.2 to 1.5 nA as previously described in this cell line [9,11,18] and in the parental NG108-15 cells [7,10,15]. Fig.…”

“…Thus, it is likely that the partial blockade of M-current inhibition induced by the four different agonists is closely related to the cellular NAD + level as suggested for ml mAChRs. It is likely that slow M-current inhibition is mediated by a diffusible second messenger(s) [5,9,10,19]. As has been proposed, suppression of M-current by angiotensin II seems to share a common signalling pathway with suppression by muscarinic agonists [19].…”

“…NGPMI 27 cells, a subclone of ml-mAChR-transformed NG108 15 cells [9], were used. Cells were maintained in culture and differentiated with 0.25 mM dibutyryl cAMP for 12-21 days as described previously [10].…”

Functional expression of the calcium release channel from skeletal muscle ryanodine receptor cDNA

“…pRRSl1 was constructed as follows (see [12] for cDNA clones and nucleotide numbers identifying restriction endonuclease sites (6467) fragment from pRRSlc, the XhoI(6467)/&mHI(lO983) fragment from pRRS2M and the 4.3-kb BumHI(10983)/XbaI(vector) fragment from pRRS3 were ligated with the XbaI/NindIII fragment from pSP64 (Promega) to yield pRRSl0. The 15.3-kb Hind111 fragment containing the entire protein-coding sequence from pRRSl0 was cloned into theHind site of pKNH [15] to yield pRRSl1. CHO cells were transfected with fit&cleaved pRRSl1 and G418-resistant clones were screened by RNA blotting analysis as in [12].…”

Involvement of protein tyrosine phosphatases in activation of the trimeric G protein Gq/11

“…We then examined the IP 3 -Ca 2+ signaling through other G q/11 protein-coupled receptors, M1 and M3 mAChRs (Fukuda et al, 1988). As shown in Figure 2b, agonist (carbachol)-induced IP 3 formation was almost completely abolished by the presence of the PTP inhibitor vanadate in M1 or M3 mAChRsexpressing CHO cells.…”