title: Pyridostigmine prevents haemodynamic alterations but does not affect their nycthemeral oscillations in infarcted mice.
abstract: The increase in acetylcholine yielded by pyridostigmine (PYR), an acetylcholinesterase inhibitor, was evaluated for its effect on the haemodynamic responses-mean arterial pressure (MAP) and heart rate (HR)-and their nycthemeral oscillation in mice before and one week after myocardial infarction (MI). Mice were anesthetized (isoflurane), and a telemetry transmitter was implanted into the carotid artery. After 5 days of recovery, the MAP and HR were recorded for 48 h (10 s every 10 min). Following this procedure, mice were submitted to surgery for sham or coronary artery ligation and received drinking water (VEHICLE) with or without PYR. Five days after surgery, the haemodynamic recordings were recommenced. Sham surgery combined with VEHICLE did not affect basal MAP and HR; nevertheless, these haemodynamic parameters were higher during the night, before and after surgery. MI combined with VEHICLE displayed decreased MAP and increased HR; these haemodynamic parameters were also higher during the night, before and after surgery. Sham surgery combined with PYR displayed similar results for MAP as sham combined with VEHICLE; however, PYR produced bradycardia. Nevertheless, MI combined with PYR exhibited no change in MAP and HR, but these haemodynamic parameters were also higher during the night, before and after surgery. Therefore, MI decreased MAP and increased HR, while PYR prevented these alterations. Neither MI nor PYR affected nycthemeral oscillations of MAP and HR. These findings indicate that the increase in acetylcholine yielded by PYR protected the haemodynamic alterations caused by MI in mice, without affecting the nycthemeral haemodynamic oscillations.
authors.affiliation: Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Wesley G
authors.initials: WG
authors.lastname: Corrêa
authors.affiliation: Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Marina T
authors.initials: MT
authors.lastname: Durand
authors.affiliation: Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Christiane
authors.initials: C
authors.lastname: Becari
authors.affiliation: Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Geisa C S V
authors.initials: GC
authors.lastname: Tezini
authors.affiliation: Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS, USA.
authors.forename: Jussara M
authors.initials: JM
authors.lastname: do Carmo
authors.affiliation: Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Mauro
authors.initials: M
authors.lastname: de Oliveira
authors.affiliation: Department of Pathology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Cibele M
authors.initials: CM
authors.lastname: Prado
authors.affiliation: Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Rubens
authors.initials: R
authors.lastname: Fazan
authors.affiliation: Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil. Electronic address: hcsalgado@fmrp.usp.br.
authors.forename: Helio C
authors.initials: HC
authors.lastname: Salgado
mesh_terms: D000818:Animals; D062186:Arterial Pressure / Q000187:drug effects; D002800:Cholinesterase Inhibitors / Q000008:administration & dosage*; D002940:Circadian Rhythm / Q000187:drug effects / Q000502:physiology*; D004195:Disease Models, Animal; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009203:Myocardial Infarction / Q000188:drug therapy*; D009206:Myocardium / Q000473:pathology; D011729:Pyridostigmine Bromide / Q000008:administration & dosage*; D013686:Telemetry
chemical_list: D002800:Cholinesterase Inhibitors; D011729:Pyridostigmine Bromide
keywords: Arterial pressure; Heart rate; Mice; Myocardial infarction; Nycthemeral haemodynamic oscillations; Parasympathetic nervous system; Pyridostigmine