Krumschnabel 2001 Gen Comp Endocrinol
| Krumschnabel G, Manzl C, Schwarzbaum PJ (2001) Metabolic responses to epinephrine stimulation in goldfish hepatocytes: evidence for the presence of alpha-adrenoceptors. Gen Comp Endocrinol 121:205-213. |
Krumschnabel G, Manzl C, Schwarzbaum PJ (2001) Gen Comp Endocrinol
Abstract: The effect of epinephrine on various aspects of cellular metabolism was studied in hepatocytes from the goldfish Carassius auratus. Epinephrine increased cytosolic free calcium ([Ca2+](i)) from a baseline value of 108 +/- 22 nM to a peak value of 577 +/- 127 nM in suspensions of hepatocytes. Responses of single cells ranged from a single spike (66% of hepatocytes) to variable oscillatory patterns (34%). The increase in [Ca(2+)](i) was independent of the presence of extracellular Ca2+ and was prevented by the alpha-adrenergic antagonist phentolamine. Cellular glucose release induced by epinephrine (1.7- to 3.2-fold) was significantly reduced in Ca2+-depleted cells and in the presence of phentolamine, providing evidence for the co-occurrence of alpha-adrenoceptors and a Ca2+-independent, presumably beta-adrenergic, system in these cells. Furthermore, epinephrine stimulated oxygen consumption in a Ca2+-dependent manner, which was not due to stimulated Na(+) pump activity. An increased rate of acid secretion of 50%, evoked by epinephrine, appears to be mediated by enhanced Na(+)/H(+) exchange but did not result in intracellular alkalization • Keywords: epinephrine, goldfish, cytosolic calcium concentration, alpha-adrenoceptor, glucose release
• O2k-Network Lab: AT Innsbruck Oroboros
Labels:
Organism: Fishes
Tissue;cell: Liver
Preparation: Intact cells
Coupling state: ROUTINE
HRR: Oxygraph-2k
