A comparative study on the innervation and the vascularization of the bulbus arteriosus in teleost fish.
The structure of the bulbus arteriosus of a wide range of teleost fish is described with particular reference to the vascularization and innervation. The adventitia of the organ consists of blood vessels and large nerve bundles in a collagen matrix. The nerve bundles contain monoamines, and fluorescence studies show small terminal bundles penetrating the muscular media; this is confirmed by electron microscopy. The media consists of an extensive elastic tissue matrix with a spiral arrangement of smooth muscle cells joined end to end by desmosomes and presumed electronic junctions. The muscles cells are innervated only at the adventitia/media boundary and the significance of this innervation is discussed. It is proposed that there is a correlation between the degree of vascularization and innervation and the activity of a particular species of fish.
D000818:Animals; D001369:Axons; D001808:Blood Vessels; D003326:Coronary Circulation; D005399:Fishes; D006321:Heart / Q000294:innervation*; D008856:Microscopy, Fluorescence; D009130:Muscle, Smooth