HORMONAL RESPONSE OF PRIMARY HEPATOCYTES OF THE CLAWED TOAD, XENOPUS-LAEVIS

Freshly isolated hepatocytes of the clawed toad, Xenopus laevis, were cultured for at least 3 days. The viability of the cells was characterized using staining and biochemical methods. In particular, the glucose and glycogen balance was tested. After culture for 16-20 hrs, the cells were subjected to hormonal treatment. Both adrenaline and arginine vasotocin stimulated the release of glucose in a dose dependent manner. 10-(6) M concentrations were strongly effective. The determination of the glycogen balance made it clear that the glucose release is mainly due to glycogenolysis. Using receptor antagonists and agonists, it has been shown that the effect of adrenaline is clearly mediated by beta-type receptors. Arginine vasotocin stimulated glycogenolysis via a type of receptor which is similar to the V-2-receptor of mammals. This means that cAMP is involved in the response to both types of hormones which is in contrast to that which is known about the effect of nonapeptides on the liver of mammals.