Dissociation of alpha-adrenergic and cholinergic stimulated inositol trisphosphate-dependent calcium mobilization at the "post-receptor" level.
Carbachol stimulated inositol trisphosphate (IP3) production and subsequent calcium mobilization in parotid cells are almost completely inhibited by neomycin. In contrast epinephrine stimulated IP3 production and calcium mobilization are much less sensitive to such inhibition. Since neomycin exerts its effects primarily at the level of inositol phosphate production and action, cholinergic and alpha adrenergic stimulation of IP3 dependent calcium mobilization may proceed through different "post-receptor" signal transduction mechanisms in parotid cells.
Kowatch
M A
MA
Gerontology Research Center, National Institute on Aging, Baltimore, MD 21224.
Roth
G S
GS
D000818:Animals; D001667:Binding, Competitive; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels; D002217:Carbachol / Q000494:pharmacology; D004837:Epinephrine / Q000494:pharmacology; D015544:Inositol 1,4,5-Trisphosphate; D053496:Inositol 1,4,5-Trisphosphate Receptors; D007295:Inositol Phosphates / Q000096:biosynthesis / Q000378:metabolism / Q000502:physiology*; D008297:Male; D009355:Neomycin / Q000494:pharmacology; D010277:Parasympathomimetics / Q000494:pharmacology*; D010306:Parotid Gland / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000187:drug effects / Q000378:metabolism*; D018160:Receptors, Cytoplasmic and Nuclear; D015398:Signal Transduction / Q000187:drug effects; D013403:Sugar Phosphates / Q000502:physiology*; D013566:Sympathomimetics / Q000494:pharmacology*
D015220:Calcium Channels; D053496:Inositol 1,4,5-Trisphosphate Receptors; D007295:Inositol Phosphates; D010277:Parasympathomimetics; D011956:Receptors, Cell Surface; D018160:Receptors, Cytoplasmic and Nuclear; D013403:Sugar Phosphates; D013566:Sympathomimetics; D015544:Inositol 1,4,5-Trisphosphate; D002217:Carbachol; D009355:Neomycin; D002118:Calcium; D004837:Epinephrine