Modulation of Bradykinin-Induced Inositol Trisphosphate Release in a Novel Neuroblastoma X Dorsal Root Ganglion Sensory Neuron Cell Line (F-11) |
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Authors: | Paul C Francel Richard J Miller Glyn Dawson† |
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Institution: | Department of Pharmacological and Physiological Sciences, University of Chicago, Chicago, Illinois, U.S.A.;Department of Biochemistry, University of Chicago, Chicago, Illinois, U.S.A.;Department of Pediatrics, Joseph P. Kennedy, Jr. Mental Retardation Research Center, University of Chicago, Chicago, Illinois, U.S.A. |
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Abstract: | In the mouse neuroblastoma x dorsal root ganglion hybrid cell line F-11, bradykinin receptor stimulation induced the release of inositol-1,4,5-trisphosphate (IP3) and inositol-1,4-bisphosphate (IP2). Maximal stimulation of 2-3H]IP3 and 2-3H]IP2 release by bradykinin in the absence of LiCl occurred at 7 (or less) and 15 s, respectively, with average levels of 5.7-(IP3) and 3.4-(IP2) fold of control values. The EC50 for bradykinin was 33 +/- 5 nM. IP3 and IP2 concentrations returned to basal levels approximately 1 min after bradykinin addition. Bradykinin-induced IP3 release was blocked by several novel bradykinin analogues. In particular, D-Arg0]-Hyp3-Thi5,8-D-Phe7]-bradykinin Hyp, hydroxyproline; Thi, beta-(2-thienyl)-L-alanine] blocked IP3 production in a dose-dependent fashion. Several of these analogues alone showed little or no agonist activity. The bradykinin receptor may be coupled to phospholipase C via a GTP-sensitive protein (Gi or Go), as preincubation for 18-20 h with pertussis toxin decreased IP3 concentrations by 45%. Bradykinin is also known to modulate the concentrations of other second messengers in neurons, increasing the concentrations of Ca2+, diacylglycerol (DG), and cyclic GMP and decreasing the concentration of cyclic AMP. These second messengers modulated bradykinin-dependent IP3 release to varying degrees. A23187, a Ca2+ ionophore, produced a 37% decrease in IP3 concentration. 12-O-Tetradecanoylphorbol-13-acetate, which mimics the effects of DG and activates protein kinase C, inhibited IP3 release by 80%. Dibutyryl cyclic GMP produced little or no inhibition of IP3. D-Ala2,D-Leu5]Enkephalin (DADLE), an opioid peptide that decreases cyclic AMP concentrations, likewise had no effect.(ABSTRACT TRUNCATED AT 250 WORDS) |
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Keywords: | Bradykinin Inositol trisphosphate Bradykinin antagonists Dorsal root ganglion |
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