Adenylyl cyclase cascade, involvement

Stimulation of glycogen breakdown involves consumption of molecules of ATP at three different steps in the hormone-sensitive adenylyl cyclase cascade (Figure 15.19). Note that the cascade mechanism is a means of chemical amplification, because the binding of just a few molecules of epinephrine or glucagon results in the synthesis of many molecules of cyclic / MP, which, through the action of c/ MP-dependent protein kinase, can activate many more molecules of phosphorylase kinase and even more molecules of phosphorylase. For example, an extracellular level of 10 to 10 M epinephrine prompts the for-... 

Adenylyl cyclase in learning and memory. The cAMP-signal transduction cascade has been demonstrated to play a role critical to the formation of long-term memory in both cellular models and in animals. The specific adenylyl cyclases involved are being identified by current research. In AC1 mutant mice there is a partial disruption of long-term potentiation (LTP), a cellular model of... 

Functional evidence also suggests that the adenylyl cyclase second messenger cascade in the cerebellum may be involved in cannabinoid withdrawal. An intrac-erebellar infusion of the cAMP blocker Rp-8Br-cAMPs reduced several behavioral... 

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