Adrenergic Nerves and Monoamine‐containing Cells in the Mammalian Endocrine Pancreas:a Comparative Study

Autonomic regulation of islet hormone secretion - Implications for health and disease

“…An extensive adrenergic innervation of the islets was later shown by fluorescence microscopy. A rich supply of nerve endings containing amine in close connection with the islet endocrine cells was made visible in several species [6]. Furthermore, islet innervation of adrenergic nerves has also been supported by the localisation in islets of labelled noradrenaline or 5-hydroxytryptophan from intact animals that had been given these neurotransmitters in vivo [3].…”

“…Sometimes more than three nerve terminals were found to approach a single endocrine cell [3,4]. The nature of these islet nerves was studied using histochemical and fluorescene staining techniques during the 1950 s and 1960 s. These techniques revealed localisation of cholinesterase to some of the islet nerves and catecholamines to other nerves, indicating that both cholinergic and adrenergic nerves innervate the islets [5,6]. In general, the nerve fibres enter the islets along the vessels and form either a peri-insular network in the mantle zone of the islet or pass directly to an islet endocrine cell.…”

Thyrotropin-releasing Hormone in the Pancreas and Brain of the Rat Is Regulated by Central Noradrenergic and Dopaminergic Pathways

“…This selective reduction in pancreatic NE by guanethidine can be accounted for by the anatomical distribution of the catecholamines within the pancreas. NE is predominantly found within the adrenergic nerves that innervate the pancreas (35), and the destruction of the ganglia supplying these nerves would be expected to be accompanied by a lowering of NE concentrations. On the other hand, the predominant location of DA is within the islets themselves, where presumably it would escape the effects of guanethidine.…”

Further Studies on 5‐hydroxytryptamine Transport in Pancreatic Islets and Isolated Β‐cells

“…To obtain a crude preparation of thrombocytes centrifugation at 100 -200 g for 15 -20 min is necessary (see Murphy, Colbum, Davis & Bunney, 1969), while to obtain an enriched fraction of nerve endings usually even higher speeds are necessary (see Franke & Uebelhack, 1978). Nerve terminals capable of accumulating 5-HT are also normally rare in mice (Falck & Hellman, 1963, Cegrell, 1968. Table 1 shows values for the labelled 5-HT (0.2 or 100 ,uM) uptake by suspended /-cells calculated as mmol/kg dry weight of cells.…”