title: Adenosine effects upon the spontaneous quantal transmitter release at the frog neuromuscular junction in the presence of protein kinase C-blocking and -activating agents.
abstract: This paper gives experimental evidence involving protein kinase C (PKC) in the inhibitory effects of adenosine (ADO) upon the spontaneous transmitter release at the frog neuromuscular junction. In the presence of two PKC inhibitors--polymyxin B (5 x 10(-6) mol/l) and H-7 (10(-5) mol/l), both adenosine (5 x 10(-5) mol/l) and its stable analogue 1-PIA (5 x 10(-8) mol/l), significantly increased the rate of the spontaneous release of acetylcholine quanta. Even when PKC was activated with OAG (5 x 10(-6) mol/l) or TPA (162 x 10(-9) mol/l) and quantal release was increased greatly, ADO still inhibited release. ADO deaminase increased the PKC-induced activation of the transmitter release significantly.
authors.affiliation: Department of Physiology, Institute of Medicine and Pharmacy, Iaşi, Romania.
authors.forename: D D
authors.initials: DD
authors.lastname: Brănişteanu
authors.forename: D D
authors.initials: DD
authors.lastname: Brănişteanu
authors.forename: A
authors.initials: A
authors.lastname: Covic
authors.forename: E
authors.initials: E
authors.lastname: Brailoiu
authors.forename: D N
authors.initials: DN
authors.lastname: Serban
authors.forename: I D
authors.initials: ID
authors.lastname: Haulica
mesh_terms: D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D000109:Acetylcholine / Q000378:metabolism* / Q000502:physiology; D000241:Adenosine / Q000494:pharmacology*; D000818:Animals; D004075:Diglycerides / Q000494:pharmacology*; D005989:Glycerides / Q000494:pharmacology*; D066298:In Vitro Techniques; D007546:Isoquinolines / Q000494:pharmacology; D009469:Neuromuscular Junction / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D010879:Piperazines / Q000494:pharmacology; D011112:Polymyxin B / Q000494:pharmacology*; D011113:Polymyxins / Q000494:pharmacology*; D011480:Protease Inhibitors / Q000494:pharmacology; D011493:Protein Kinase C / Q000378:metabolism / Q000502:physiology*; D011895:Rana ridibunda
chemical_list: D004075:Diglycerides; D005989:Glycerides; D007546:Isoquinolines; D010879:Piperazines; D011113:Polymyxins; D011480:Protease Inhibitors; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; C038237:1-oleoyl-2-acetylglycerol; D011493:Protein Kinase C; D011112:Polymyxin B; D000241:Adenosine; D000109:Acetylcholine