Cyclic adenosine monophosphate assay

Guerrant RL, Brunton LL, Schnaitman RC, Rebhun LI, Gilman AG Cyclic adenosine monophosphate and alteration of Chinese hamster ovary cell morphology A rapid, sensitive in vitro assay for the entertoxins of Vibrio cholerae and Escherichia coli. Infect Immun 1974 10 320-327. 

Pennington (PI) and Uberti (U1) first introduced the technique of liquid chromatographic enzyme assays by using the ion-exchange mode of HPLC in their analyses of 3, 5 -cyclic adenosine monophosphate phosphodiesterase and adenosine deaminase, respectively. Since that time, a number of liquid chromatographic enzyme assays have been developed. 

The measurement of TSH was originally based on bioassays such as the stimulation of colloid droplet formation in the guinea pig thyroid gland and the release of labeled thyroidal iodide into mouse blood. These early in vivo bioassays, however, were of limited sensitivity and precision and were not applicable to the measurement of TSH in unfractionated serum. Most TSH bioassays have involved the in vitro stimulation of thyroid cyclic adenosine monophosphate (cAMP) or adenylate cyclase activity. The rat FRTL-5 thyroid cell line is an example of a particularly convenient and precise assay system. Unfortunately, such methods require purification and concentration of TSH from serum before assay. Sensitive detection of TSH in unfractionated serum is possible using a cytochemical bioassay, but this procedure is technically difficult and time-consuming. At present, immunoassay is the procedure of choice for the measurement of serum TSH in the clinical laboratory. 

Fig. 4 Assays for G-protein-coupled receptors. The two main ciasses are binding and functional assays. Binding assays detect compounds that are ligands of the receptor. Functional assays probe the signaling of the receptor within the cell. Gs/i and Gq/i, G-proteins PLC, phospholipase C AC, adenylyl cyclase DAG, diacylglycerol cAMP, cyclic adenosine monophosphate PKC, protein kinase C PKA, protein kinase A (PKA) lns(l,4,5)P3, inositol phosphates P-CREB, phosphorylated cAMP response element binding protein CRE, cAMP regulatory element.

The cyclic adenosine monophosphate (cAMP) assay, in which the ability to inhibit forskolin-induced cAMP production is measured. 

OTHER TECHNIQUES A number of other techniques have been used to determine specific organic phosphorus compounds in the environment, including a firefly luciferase assay for adenosine di- and triphosphate (Kaplan and Bott, 1985), a protein assay for cyclic adenosine monophosphate (Francko and Wetzel, 1982) and cetryltrimethylammonium bromide precipitation of dissolved RNA and DNA in marine and freshwaters (Karl and Bailiff, 1989). However, none of these are regularly used in studies of organic phosphorus dynamics in aquatic ecosystems. 

A polyacrylamide-boronate affinity gel, Affi-gel 601 , has been used for the separation of cyclic adenosine monophosphate, cyclic guanosine monophosphate, and cyclic cytidine monophosphate from their corresponding 5-nucleotides and nucleosides. A simple direct assay of 3 5 -cyclic nucleotide phosphodiesterase activity has been developed, based on the use of the gel. 

Bressan, R. A. Ross, C. W. Attempts to detect cyclic adenosine 3 5 -monophosphate in higher plants by three assay methods. Plant Physiol., 1976, 57, 29-37. 

Cyclic 3 ,5 -adenosine monophosphate phosphodiesterase (EC 3.1.4.17) activity, assayed in rat pineal organ cultures at 1 p,M substrate concentration, was significantly increased 4 h after choleragen exposure and was maximally activated (170 percent of control) after 6 h, thereafter declining to basal levels (Minneman and Iversen 1976). 

Wandelt et al. [87] have reported the application of a FILA for nucleotide monitoring. The assays were based on the fluorescence quenching of 3-diphenyl-6-vinyl-1 //-pyrazole 3.4-/ quinoline (PAQ), by guanosine 30,50-cyclic monophosphate (cGMP), adenosine 30,50-cyclic monophosphate (cAMP), and cytidine 30,50-cyclic monophosphate (cCMP). Although no analytical characterization of the polymers was reported, the authors carried out a rebinding study to ascertain the applicability of the MIPs for such application. 

A more recent cell-based in vitro assay involves the use of the microphysiometer, a sensitive extracellular pH sensor, which has been used to measure luminal (or apical) secretion and basolateral release of OH- as well as liberation of acidic metabolites in rabbit gastric glands. Adenosine 3, 5 -cyclic monophosphate stimulation produced a biphasic change... 

P.B., and Chau, V. (1981) Fluoromet-ric assay for adenosine 3, 5 -cyclic monophosphate-dependent protein kinase and phosphoprotein phosphatase activities. Proc. Nad. Acad. Sci. U.S.A., 78, 6048-6050. 

The poly(ADP-ribose) glycohydrolase has been pmified from a number of sources 84, 171). It is an exoglycohydrolase, localized in the nucleus 31, 136), and is readily inhibited by NAD, ADP-ribose, adenosine 3, 5 -cyclic monophosphate, p-chloromercuribenzoate, and, in some cases, DNA 135, 136). The enzyme, in the presence of added nicotinamide, did not catalyze the synthesis of NAD it did not hydrolyze the ribose to ribose linkage of iso-ADP-ribose or the terminal ADP-ribose to histone bond 31,84,171). [An assay for the enzjrme has... 

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