title: Atrial Natriuretic Peptide Inhibits Spontaneous Contractile Activity of Lymph Nodes.
abstract: Atrial natriuretic peptide dose-dependently inhibited spontaneous phase and tonic activity of smooth muscle strips from the capsule of isolated bovine mesenteric lymph nodes. Pretreatment with L-NAME, diclofenac, and methylene blue had practically no effect on the peptide-induced relaxation responses. In contrast, glibenclamide significantly reduced the inhibitory effect of atrial natriuretic peptide. We suppose that the NO-dependent and cyclooxygenase signaling pathways are not involved in implementation of the inhibitory effects of atrial natriuretic peptide. ATP-sensitive K(+)-channels of the smooth muscle cell membrane are the last component in the signaling pathway leading to relaxation of smooth muscles of the lymph node capsule caused by atrial natriuretic peptide; activation of these channels leads to membrane hyperpolarization and smooth muscle relaxation.
authors.affiliation: I. P. Pavlov Institute of Physiology of Russian Academy of Sciences, St. Petersburg, Russia. gilobov@yandex.ru.
authors.forename: G I
authors.initials: GI
authors.lastname: Lobov
authors.affiliation: I. P. Pavlov Institute of Physiology of Russian Academy of Sciences, St. Petersburg, Russia.
authors.forename: M N
authors.initials: MN
authors.lastname: Pan'kova
mesh_terms: D000818:Animals; D009320:Atrial Natriuretic Factor / Q000494:pharmacology / Q000502:physiology*; D002417:Cattle; D008198:Lymph Nodes / Q000502:physiology*; D009119:Muscle Contraction; D009130:Muscle, Smooth
chemical_list: D009320:Atrial Natriuretic Factor
keywords: atrial natriuretic peptide; contractile activity; lymph node capsule; smooth muscle