Innervation of the human cardiac conduction system. A quantitative immunohistochemical and histochemical study

S J Crick, J Wharton, M N Sheppard, D Royston, M H Yacoub, R H Anderson, J M Polak
1994 Circulation  
Cardiac conduction is influenced by peptidergic mechanisms as well as classic neurotransmitters. The distribution of peptide-containing nerves has not been well defined. Methods and Results Immunofluorescence and histochemical techniques were used to visualize the innervation of the human conduction system and to distinguish nerve subpopulations according to their peptide and enzyme content. Nerve fibers and fascicles displaying immunoreactivity for protein gene product 9.5 (PGP 9.5) were more
more » ... umerous in the sinus and atrioventricular nodes than in the penetrating bundle, bundle branches, and adjacent myocardium. The relative density of innervation was greater in the central region of the sinus node than in the peripheral regions. Nerve densities were also higher in the transitional region of the atrioventricular node compared with its compact region. Acetylcholinesterase (AChE)-positive nerves were the main subtype identified in the sinus and atrioventricular nodes, representing half to two thirds of the stained area occu-
doi:10.1161/01.cir.89.4.1697 pmid:7908612 fatcat:pt5ywoawyrhq7j4q5pvenmoleq