Abstract |
Preincubation of murine neuroblastoma cells (clone N1E-115) with terbium chloride resulted in a significant potentiation of carbachol-mediated increase in cyclic GMP formation. This effect was accompanied by a shift of the peak response from 30 s to 120 s and a 6-fold decrease in carbachol concentration producing half-maximal responses, in addition to a significant increase in the Hill coefficient. Terbium ions also caused a significant decrease in the affinity and an increase in the maximum binding of [3H] quinuclidinyl benzilate to muscarinic receptors, the change in affinity being mainly due to a decrease in the association rate. Preincubation of cells with 1 mM carbachol for 4 h (the desensitized state of the muscarinic receptor) resulted in a decrease in the ability of terbium to alter [3H] quinuclidinyl benzilate binding. The effects of terbium reported here might be due to its affecting muscarinic receptor-effector coupling, which is considered to be lost upon receptor desensitization.
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Authors | E E El-Fakahany, M Pfenning, E Richelson |
Journal | Journal of neurochemistry
(J Neurochem)
Vol. 42
Issue 3
Pg. 863-9
(Mar 1984)
ISSN: 0022-3042 [Print] England |
PMID | 6319610
(Publication Type: Journal Article)
|
Chemical References |
- Receptors, Muscarinic
- Terbium
- Quinuclidinyl Benzilate
- Cyclic GMP
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Topics |
- Animals
- Cell Line
- Cyclic GMP
(metabolism)
- Kinetics
- Mice
- Neuroblastoma
(metabolism)
- Quinuclidinyl Benzilate
(metabolism)
- Receptors, Muscarinic
(drug effects, metabolism)
- Terbium
(pharmacology)
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