Ganglionic and non-ganglionic neurons in frog heart: do they differ?

  • Darius Batulevičius Institute of Anatomy, Faculty of Medicine, Lithuanian University of Health Sciences, Kaunas
  • Gertrūda Skripkienė Institute of Anatomy, Faculty of Medicine, Lithuanian University of Health Sciences, Kaunas
  • Greta Graužinytė Institute of Anatomy, Faculty of Medicine, Lithuanian University of Health Sciences, Kaunas
  • Augustina Grigaitė Institute of Anatomy, Faculty of Medicine, Lithuanian University of Health Sciences, Kaunas
  • Valdas Skripka Institute of Anatomy, Faculty of Medicine, Lithuanian University of Health Sciences, Kaunas
Keywords: axon, dendrites, soma, heart, autonomic, ganglion

Abstract

This study was designed to compare the morphology of neurons in relation to their distance from the major nerve trunks in the heart of the frog Rana temporaria. Seventy-nine intracardiac neurons were labelled intracellularly with fluorescent markers Lucifer Yellow CH and Alexa Fluor 568. The neurons located on the extensions of the vagus nerve were considered as ganglionic, while neurons spread loosely at further distance from these extensions were considered as non-ganglionic. The mean area of the soma in ganglionic neurons was about 25% larger than in non-ganglionic neurons. Ganglionic neurons had a higher soma area/nucleus area ratio than non-ganglionic neurons. Although both the total number and the total length of dendrite-like processes was similar between the two groups, ganglionic neurons had significantly fewer dendrite-like processes from the soma (1.5±0.3 vs. 3.9±1.0; P<0.05) and shorter total length of these processes from the soma (63±18 μm vs. 178±51 μm; P<0.05). In conclusion, ganglionic and non-ganglionic frog intracardiac neurons exhibit substantial morphological differences. We hypothesize that these differences may indicate different projections or variations in the number of their preganglionic inputs.
Published
2017-09-18
Section
Articles