title: Changes in parasympathetic system in medulla oblongata in male pigs in the course of tachycardia-induced cardiomyopathy.
abstract: BACKGROUND
  Autonomic imbalance constituting a fundamental feature of heart failure (HF) has been assessed mainly at the periphery. Changes in the functioning of autonomic centers in the brain remain unclear. We investigated the molecular elements of parasympathetic system, i.e. α7 nicotinic acetylcholine receptor (α7nAChR) and enzymes metabolizing acetylcholine (acetylcholinesterase, AChE, choline acetyltransferase, ChAT) in medulla oblongata (MO) of male pigs with chronic tachycardia-induced cardiomyopathy.
  
  
  METHODS
  The mRNA levels of AChE, ChAT, α7nAChR and X-box binding protein 1 (spliced form, XBP1s) in MO were analyzed using qPCR, AChE and ChAT activities using spectrophotometry, proteasome activity using fluorometry, and the protein level of α7nAChR using Western blotting.
  
  
  RESULTS
  The development of systolic HF was accompanied by an increase in circulating catecholamines, a decrease in the AChE and α7nAChR mRNA in MO, an increase in AChE activity (all p<0.05), and no change in either the mRNA or activity of ChAT. Both circulating catecholamine levels and AChE activity were inversely related to systolic function of left myocardial ventricle (p<0.05). The level of α7nAChR protein in MO and its cytoplasmatic fraction were higher in pigs with moderate and severe HF as compared to the other animals (p<0.01). There was no difference in proteasome activity in MO between diseased and healthy animals, whereas the XBP1s mRNA decreased during HF progression (p<0.05).
  
  
  CONCLUSIONS
  Molecular elements of parasympathetic system are changed within the medulla oblongata during the progression of systolic non-ischemic heart failure in male pigs, indicating a functional link between MO and heart in HF.
authors.affiliation: Regional Specialist Hospital in Wroclaw, Research and Development Centre, Wroclaw, Poland; Department of Heart Diseases, Wroclaw Medical University, Wroclaw, Poland.
authors.forename: Alicja
authors.initials: A
authors.lastname: Tomaszek
authors.forename: Liliana
authors.initials: L
authors.lastname: Kiczak
authors.forename: Jacek
authors.initials: J
authors.lastname: Bania
authors.forename: Paweł
authors.initials: P
authors.lastname: Krupa
authors.forename: Urszula
authors.initials: U
authors.lastname: Pasławska
authors.forename: Maciej
authors.initials: M
authors.lastname: Zacharski
authors.forename: Adrian
authors.initials: A
authors.lastname: Janiszewski
authors.forename: Tadeusz
authors.initials: T
authors.lastname: Stefaniak
authors.forename: Dorota
authors.initials: D
authors.lastname: Zyśko
authors.forename: Hossein
authors.initials: H
authors.lastname: Ardehali
authors.forename: Ewa A
authors.initials: EA
authors.lastname: Jankowska
authors.forename: Piotr
authors.initials: P
authors.lastname: Ponikowski
mesh_terms: D000818:Animals; D009202:Cardiomyopathies / Q000097:blood* / Q000209:etiology / Q000503:physiopathology; D002395:Catecholamines / Q000097:blood; D018450:Disease Progression; D008297:Male; D008526:Medulla Oblongata / Q000378:metabolism*; D010275:Parasympathetic Nervous System / Q000378:metabolism*; D011897:Random Allocation; D013552:Swine; D013610:Tachycardia / Q000097:blood* / Q000150:complications / Q000503:physiopathology
chemical_list: D002395:Catecholamines
keywords: Acetylcholinesterase; Choline acetyltransferase; Medulla oblongata; Parasympathetic system; Pigs; Tachyarrhythmic experimental model of heart failure; α7 acetylcholine nicotinic receptor