CAMP signaling

Tabakoff B, Nelson E, Yoshimura M et al (2001) Phosphorylation cascades control the actions of ethanol on cell cAMP signalling. J Biomed Sci 8 44—51... 

Gao and Yamaguchi, 1999b Mouse bone marrow cells cultured for 7 d with bone resorbing factors (PTH, PGE2, EPS) +/- genistein osteoclast formation assessed by TRAP enzyme Genistein (10 Yi0 M) inhibited osteoclast formation. Mechanism may involve cAMP signalling. 

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... 

Cooper, D., Mons, N. and Karpen, J. W. Adenylyl cyclases and the interaction between calcium and cAMP signaling. Nature 374 421-424,1995. 

Abnormalities in G protein subunits/cAMP signaling pathway have been observed in bipolar disorder 897... 

The three best-known examples of biochemical oscillations were found during the decade 1965-1975 [40,41]. These include the peroxidase reaction, glycolytic oscillations in yeast and muscle, and the pulsatile release of cAMP signals in Dictyostelium amoebae (see Section V). Another decade passed before the development of Ca " " fluorescent probes led to the discovery of oscillations in intracellular Ca +. Oscillations in cytosolic Ca " " have since been found in a variety of cells where they can arise spontaneously, or after stimulation by hormones or neurotransmitters. Their period can range from seconds to minutes, depending on the cell type [56]. The oscillations are often accompanied by propagation of intracellular or intercellular Ca " " waves. The importance of Ca + oscillations and waves stems from the major role played by this ion in the control of many key cellular processes—for example, gene expression or neurotransmitter secretion. 

Theoretical models shed light on additional aspects of pulsatile cAMP signaling in Dictyostelium. First, like Ca + spikes, cAMP pulses are frequency encoded. Only pulses delivered at 5-min intervals are capable of accelerating slime mold development after starvation. Simulations indicate that frequency encoding is based on reversible receptor desensitization [76]. The kinetics of receptor resensitization dictates the interval between successive pulses required for a maximum relay response [78]. Second, cAMP oscillations in... 

Studies of peripheral NE receptor function have also shown alterations in a2 receptor and cyclic adenosine 39,59-monophosphate (cAMP) function in patients with PTSD. Decreases in platelet adrenergic a2-receptor number (Perry et al. 1987), platelet basal adenosine, isoproterenol, forskohn-stimulated cAMP signal transduction (Lerer et al. 1987), and basal platelet monoamine oxidase (MAO) activity (Davidson et al. 1985) have been found in PTSD. These findings may reflect chronic high levels of NE release which lead to compensatory receptor down-regulation and decreased responsiveness. 

Fiouslay, M.D. and Milligan, G. Tailoring cAMP-signalling responses through isoform multiplicity (1997) Trends Biochem Sci. 22, 217-224... 

The current state of Ser/Thr phosphorylation of a protein is determined by the relative activity of Ser/Thr-specific protein kinase and protein phosphatase. It is therefore imderstandable that the cell has had to develop special mechanisms to balance the two activities with one another, and, when needed, to allow kinase or phosphatase activity to dominate. One of the best investigated examples of coordinated activity of protein kinases and protein phosphatases is the regulation of glycogen metabolism in skeletal muscle. Glycogen metabolism is an example of how two different signals, namely a cAMP signal and a Ca signal meet in one metabolic pathway and control the activity of one and the same enzyme. 

The calcium-phosphoinositide and cAMP signaling pathways oppose one another in some cells and are complementary in others. For example, vasopressor agents that contract smooth muscle act by IP3-mediated mobilization of Ca2+, whereas agents that relax smooth muscle often act by elevation of cAMP. In contrast, cAMP and phosphoinositide second messengers act together to stimulate glucose release from the liver. 

Cooper DMF, Mons N, Karpen JW (1995) Adenylyl cyclases and the interaction between calcium and cAMP signaling. Nature 374(6521) 421—424 Cowen DS, Molinoff PB, Manning DR (1997) 5HT1A receptor mediated increases in receptor expression and activation of nuclear factor-KB in transfected Chinese hamster ovarycells. Mol Pharmacol 52(2) 221-226... 

---