Adrenalin in Annelids

Abstract

1. The sympathetic nervous system and the adjuvant adrenalin-secreting system are found in their earliest form in the annelid kingdom, and consist of cells situated in the central nervous system which are the common ancestors of both, and which are both secretory and nervous in function. 2. These cells are developed in the annelid kingdom parallel with the development of a contractile vascular system, which possesses muscles comparable in physiological actions with the muscle of the vertebrate heart. 3. This vascular muscle is regulated by the processes of the common ancestral cells as well as by their secretory activity. 4. In the primitive form contractile rhythm is an intrinsic property of cardiac muscle; its nerve supply regulates the rhythm, it does not initiate it. The beat is therefore myogenic, not neurogenic. 5. The contractile vascular system of annelids is mainly branchial in function. The vertebrate heart has been derived from it by the growing around of the lateral body folds to form a new ventral surface.

Chemical and Ultrastructural Identification of 5-Hydroxytryptamine in an Identified Neuron

“…Of particular interest for the present study is the fact that two of the chromaffin cells in each ganglion are very large and easily recognized, these being the two "kolossale Ganglienzellen" or colossal cells first described by Retzius (1891) . Biedl (1910) and Gaskell (1919) both claimed to show adrenaline (epinephrine) in the ganglia by bioassays, and on this basis Gaskell (1914 ;1919) speculated that adrenaline was the chromaffin substance in the six chromaffin cells .…”

Endoreplication: A Molecular Trick during Animal Neuron Evolution

“…Invertebrates: The Case of Gastropod Molluscs Giant neurons are scattered across several invertebrate species, starting with nematodes and annelids (for a review see Bullock and Horridge 1965), but only in a few cases has the large neuronal size been specifically associated with an increased amount of DNA. A couple of very large neurons (100-120 m), the serotonergic Retzius cells of the leech Hirudo medicinalis, are probably the first examples of electrophysiologically and biochemically well-characterized giant neurons (Gaskell 1919;Coggeshall 1972). Large-sized neurons are also present in arthropodssuch as Diptera, Odonata, Chelicerata, and Arachnoidea-possessing giant cells that have been identified as motor elements (Bullock and Horridge 1965), but this does not constitute a rule among invertebrates.…”

Leeches (Hirudinea) their structure, physiology, ecology and embryology / by K.H. Mann. With an appendix on the systematics of marine leeches, by E. W. Knight-Jones.

“…Gnathobdellid leeches are clearly exceptional in this respect, and this is further evidence that their circulatory system is not homologous with the blood system of other annelids. The source of the adrenalin in leeches appears to be the ganglia of the ventral nerve cord, for Gaskell (1919) demonstrated the chromaffin staining reaction in certain cells of the ventral ganglia and identified adrenalin in ganglion extract. Perez (1942) confirmed this result, although he thought that the adrenalin was more localized in its distribution than Gaskell had suggested.…”

“…Herter (1936) found that in Erpohdella^where it is sometimes possible to observe the lateral sinuses by transparency, the rate of pumping varied from 3-7 per min at 17°C to 17-1 per min at 27°C. The mechanism controlling pumping was studied in Hirudo by Gaskell (1919). From each segmental gangHon two nerves run out on each side and send branches to the walls of the lateral sinus.…”