title: Reaction of neurons to alkaloid agonists of opioid receptors during modulation of phosphodiesterases.
abstract: We studied the effect of ultralow doses of theophylline and morphine, modulators of receptors and intracellular signal systems, on ion permeability of membranes. Theophylline and morphine in ultralow doses blocked the neuronal responses to these agents applied in physiological concentrations. Theophylline in ultralow doses attenuated, but did not completely block neuronal reaction to morphine. These findings suggest that ultralow doses of various substances producing no appreciable physiological changes can activate mechanisms providing optimum response to strong factors.
authors.affiliation: Materia Medica Holding Research-and-Production Company, Moscow.
authors.forename: O I
authors.initials: OI
authors.lastname: Epstein
authors.forename: M B
authors.initials: MB
authors.lastname: Shtark
authors.forename: T A
authors.initials: TA
authors.lastname: Zapara
authors.forename: O G
authors.initials: OG
authors.lastname: Simonova
authors.forename: A S
authors.initials: AS
authors.lastname: Ratushnyak
mesh_terms: D000470:Alkaloids / Q000494:pharmacology*; D000818:Animals; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D008195:Lymnaea; D008564:Membrane Potentials / Q000187:drug effects; D008954:Models, Biological; D009020:Morphine / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects* / Q000201:enzymology*; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism*; D011957:Receptors, Opioid / Q000819:agonists*; D015398:Signal Transduction / Q000187:drug effects; D013806:Theophylline / Q000494:pharmacology
chemical_list: D000470:Alkaloids; D011957:Receptors, Opioid; D009020:Morphine; D013806:Theophylline; D010727:Phosphoric Diester Hydrolases