Open AccessCompensatory recovery of vagal control of hemodynamics after unilateral vagotomy
Author(s) -
Chen Ln,
Zang Wj,
Yu Xj,
Jing Liu,
Li Dl,
Kong Ss,
Jian Lü,
Xu Xl
Publication year - 2008
Publication title -
physiological research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.647
H-Index - 70
eISSN - 1802-9973
pISSN - 0862-8408
DOI - 10.33549/physiolres.931095
Subject(s) - vagotomy , vagus nerve , contractility , ventricle , medicine , hemodynamics , baroreflex , denervation , anesthesia , cardiology , endocrinology , heart rate , blood pressure , stimulation
This study investigated whether each part of the heart is evenlyinnervated by the left or right vagus and observed themechanism of compensatory recovery after unilateral cervicalvagotomy. HR, BP, LVSP and ±dp/dt max all decreased one weekafter left vagotomy, whereas only BP and -dp/dt max decreasedone week after right vagotomy. Western blot analyses revealedthat the expression of M2 receptors in the left atrium and leftventricle was upregulated after subacute (1 week) left/rightvagotomy. However, significantly more cholinesterase-positivenerves in LV and RV were seen one week after unilateralvagotomy compared to the sham-operated group. In addition,baroreflex sensitivity was increased after subacute rightvagotomy. The decreasing effects of ACh (0.5 μg/kg) on LVSPand ±dp/dt max (but not on HR and BP) were facilitated bysubacute unilateral vagotomy. Our present experiments indicatethat 1) the working myocardium is innervated bilaterally by thevagus, 2) ventricular contractility is influenced more bydenervation of the left than the right vagus and 3) up-regulationof M2 muscarinic receptors in the left heart, increase ofcholinergic nerves, and high baroreflex sensitivity could beinvolved in the mechanism of compensatory hemodynamicrecovery via contralateral vagus overactivity, thereby amplifyingcontralateral vagal activity and decreasing cardiac contractility.