Development of the Adrenergic Innervation in the Myocardium and Coronary Arteries of the Dog

Autor: B. Hartmannová, J Vašků, M Gerová, S. Doležel
Rok vydání: 1990
Předmět:
Zdroj: Cells Tissues Organs. 139:191-200
ISSN: 1422-6421
1422-6405
DOI: 10.1159/000146997
Popis: The development of the adrenergic cardiac innervation was studied in premature dog fetuses, puppies and adult dogs by means of the formalin-induced fluorescence technique. A point-counting technique was used to evaluate the density of innervation. Two types of fluorescent profiles can be observed in the heart during development: (1) sprouting axons, and (2) beaded terminals. The axonal fluorescence disappears in adult neurons. A different morphology and a different time course of development enable to study separately the innervation of the myocardium (cardiomotor innervation) and that of the vessels (vasomotor innervation). The late prenatal innervation is very poor (0.1 hit). The first but very scant cardiomotor terminals appear in this period. A mature cardiomotor innervation is found in 4-month-old puppies [1.5 ± 0.3 (SD) hits]. The vasomotor innervation is shifted to the right. The development of beaded vascular terminals begins and matures 1–2 weeks later. The growing fluorescent axons reveal that the myocardium is supplied by axons of the cardiac plexus and of the perivascular nerves; the vascular wall on the other hand is supplied by the perivascular nerves only. The developmental, spatial and morphological differences in innervation suggest that two different types of neurons exist in the sympathetic ganglia: (1) neurons innervating the vessels (coronaromotor neurons), and (2) neurons innervating the myocardium (cardiomotor neurons).
Databáze: OpenAIRE