A functional study of distribution of cardiac sympathetic nerves

Abstract

In dogs with unilaterally sympathectomized hearts, the remaining intact stellate ganglion was electrically stimulated 14–58 days following sympathectomy. Pressures were simultaneously recorded from all four chambers of the heart and the resulting responses compared with those observed in similarly stimulated but nonsympathectomized animals. Augmentor responses were markedly decreased in some animals but relatively unchanged in others, and it is evident that considerable variation exists in the distribution of sympathetic fibers in different animals. A common finding was markedly delayed augmentation in which responses were practically absent during the initial periods of stimulation. Chronotropic responses appeared to be largely dependent upon intact connections via the right sympathetic nerves. It may be concluded that the sympathetic cardiac nerves from the right side go primarily to the atria and nodal tissue, with a variable supply to the ventricles. In some animals the latter supply is very large while in others it is minimal. The left sympathetic cardiac nerves furnish the major supply to the ventricles, with variable but generally lesser distribution to the atria.

Cardiac Sympathetic Nerves in Rats: Anatomical and Functional Features

“…When the right (stellate) CN in rats was stimulated, a chronotropic rather than inotropic effect was remarkably elicited, while stimulation of the left stellate CN or the thoracic CNs yielded only a marked inotropic action. Such differential effects of the electrical stimulation of the CNs of the right and left sides are much the same as those reported in dogs (LEVY et al, 1966;RANDALL et al, 1957RANDALL et al, , 1963 and may depend on different numbers of fiber populations innervating the pacemaker region and myocardium (ARMouR and RANDALL, 1975;RANDALL et' al., 1972).…”

“…In addition, one or two thoracic CNs were usually found to originate from the left second and/or third thoracic ganglia and to travel to the base of the heart. The presence of such thoracic CNs in cats, dogs and humans was reported by some investigators (MCKIBBEN and GETTY, 1968a, b;NONIDEZ, 1939;SACCOMANO et al, 1947) but was ruled out by others (MIZERES, 1955(MIZERES, , 1958RANDALL et al, 1972). Furthermore, a branch, which corresponds to Mizeres' innominate CN or cervical CNs found in dogs on the right and left, respectively (MIZERES, 1955(MIZERES, , 1958, was not evident in rats.…”

Autonomic Innervation of the Heart

“…The innominate, ventromedial, and ventrolateral nerves are the principal sympathetic cardiac nerves on the left. All of the nerves, except for the stellate cardiac nerves, are mixed, containing both sympathetic and parasympathetic components (21).…”

Gross anatomical study of the sympathetic cardiac nerves in the house musk shrew (Suncus murinus)

“…In addition, many comparative anatomical studies have been carried out on autonomic cardiac innervation in various vertebrate species, such as the calf (Shaner, 1930), rat (Gómez, 1958;Burkholder et al, 1992;Batulevičius et al, 2004), chick (Kuratani and Tanaka, 1990;Verberne et al, 1998Verberne et al, , 1999, musk shrew (Tanaka et al, 1998), guinea pig (Batulevičius et al, 2005), dog (Randall and Rohse, 1956;Itoh, 1960;Randall et al, 1963Randall et al, , 1968Randall et al, , 1972Randall et al, , 1989Szentivanyi et al, 1967;Randall, 1975, 1985;Norris and Randall, 1977;Rinkema et al, 1982;Armour, 1984, 1989;Brandys et al, 1986;Ardell et al, 1988;Armour, 1988;Gagliardi et al, 1988;Brugnaro et al, 2003), cat (Phillips et al, 1986), and primates (Riegele, 1926;Randall et al, 1971;Billman et al, 1989;Kawashima et al, 2001. Especially, Randall (1975, 1985) contributed to our knowledge of cardiac function using methods such as retrograde tracing and electrophysiology in dogs.…”