scholarly journals Studies on the specificity of immunohistochemical techniques for cyclic AMP and cyclic GMP.

1979 ◽  
Vol 27 (5) ◽  
pp. 913-923 ◽  
Author(s):  
E M Rosenberg ◽  
G LaVallee ◽  
P Weber ◽  
S M Tucci

Immunohistochemical studies employing antibodies against cyclic nucleotides indicate that cyclic AMP and cyclic GMP are localized to distinct subcellular sites. These antibodies, however, cross-react weakly with noncyclic nucleotides (eg. ATP, GTP), and therefore we investigated the speficity of the immunohistochemical technique. Slides of fetal nuclei exposed to gaseous nitrous acid demonstrated reduced immunofluorescence. The slides were then incubated with cyclic and noncyclic nucleotides, and restoration of distinct cyclic AMP and cyclic GMP staining pattern was achieved only with appropriate cyclic nucleotides. Antibodies that were used have a greater affinity for acetylated derivatives of cyclic nucleotides. By using a gas phase technique, tissue slices were acetylated and immunohistochemical staining intensity was compared with the effect of acetylation on antibody affinity for various nucleotides. Acetylation greatly increased affinity of cyclic AMP antibody for cyclic AMP but not other nucleotides, and greatly intensified cyclic AMP staining. Acetylation moderately increased affinity of cyclic GMP antibody for cyclic GMP, and moderately intensified cyclic GMP staining. Conclusion: Both nitrous acid and acetylation studies support the specificity of the immunohistochemical method for cyclic nucleotides.

1979 ◽  
Vol 57 (6) ◽  
pp. 541-546 ◽  
Author(s):  
H. L. Cailla ◽  
H. Sarles ◽  
M. V. Singer

The secretion of cyclic AMP, cyclic GMP, protein, calcium, and bicarbonate in the pancreatic juice of three nonanesthetized dogs with chronic gastric and duodenal Thomas cannulae has been studied. Intravenous infusions of increasing doses of cholecystokinin–pancreozymin (CCK) (1.5, 3, 6, 12, 24 Crick Harper-Raper (CHR) U kg−1 h−1) were administered together with a continuous submaximal dose of secretin (1 clinical unit (CU) kg−1 h−1). Doubling CCK doses every 45 min induced a parallel increase in the output of both cyclic nucleotides. Cyclic AMP output peaked at between 15 and 30 min for 3 and 6 U kg−1 h−1 of CCK and later for 12 and 24 U kg−1 h−1 of CCK whereas cyclic GMP output increased more constantly. Calcium output followed a pattern similar to that of cyclic GMP secretion. Flow rate and protein output attained their peaks at between 30 and 45 min. A strong linear correlation was found between the quantities of cyclic AMP, cyclic GMP, and the quantities of protein secreted in response to each CCK dose. This study demonstrates the presence of cyclic GMP in the canine pancreatic juice and the dose-dependent stimulation of the secretion of cyclic GMP and cyclic AMP by CCK in the presence of secretin.


1973 ◽  
Vol 59 (3) ◽  
pp. 595-606
Author(s):  
M. J. BERRIDGE

1. The nature of the cyclic AMP-receptor interaction was analysed by testing a range of cyclic nucleotides on the isolated salivary glands of adult blowflies. 2. All compounds containing modifications in the region of ribose or the phosphate ring were inactive. One compound, adenosine 3',5'-phosphorothioate, appeared to compete with cyclic AMP. 3. A number of nucleotides with alterations restricted to the base region of the molecule could stimulate secretion equally as well as cyclic AMP. 4. These observations indicate that during the action of cyclic AMP the phosphate ring and ribose sugar are critical whereas the adenine ring plays a relatively unspecific role.


Author(s):  
John W. Phillis

SUMMARY:On the basis of the information presented in this review, it is difficult to reach any firm decision regarding the role of cyclic AMP (or cyclic GMP) in synaptic transmission in the brain. While it is clear that cyclic nucleotide levels can be altered by the exposure of neural tissues to various neurotransmitters, it would be premature to claim that these nucleotides are, or are not, essential to the transmission process in the pre- or postsynaptic components of the synapse. In future experiments with cyclic AMP it will be necessary to consider more critically whether the extracellularly applied nucleotide merely provides a source of adenosine and is thus activating an extracellularly located adenosine receptor, or whether it is actually reaching the hypothetical sites at which it might act as a second messenger. The application of cyclic AMP by intracellular injection techniques should minimize this particular problem, although possibly at the expense of new difficulties. Prior blockade of the adenosine receptor with agents such as theophylline or adenine xylofuranoside may also assist in the categorization of responses to extracellularly applied cyclic AMP as being a result either of activation of the adenosine receptor or of some other mechanism. Ultimately, the development of highly specific inhibitors for adenylate cyclase should provide a firm basis from which to draw conclusions about the role of cyclic AMP in synaptic transmission. Similar considerations apply to the actions of cyclic GMP and the role of its synthesizing enzyme, guanylale cyclase.The use of phosphodiesterase inhibitors in studies on cyclic nucleotides must also be approached with caution. The diverse actions of many of these compounds, which include calcium mobilization and block of adenosine uptake, could account for many of the results that have been reported in the literature.


1973 ◽  
Vol 138 (2) ◽  
pp. 381-393 ◽  
Author(s):  
Terry B. Strom ◽  
Charles B. Carpenter ◽  
Marvin R. Garovoy ◽  
K. Frank Austen ◽  
John P. Merrill ◽  
...  

The capacity of allosensitized thymus-derived lymphocytes to destroy target cells bearing donor alloantigens is modulated by the cellular levels of cyclic AMP and cyclic GMP. Increases in the cyclic AMP levels of attacking lymphocytes by stimulation with prostaglandin E1, isoproterenol, and cholera toxin inhibit lymphocyte-mediated cytotoxicity; whereas, depletion of cyclic AMP with imidazole enhances cytotoxicity. The augmentation of cytotoxicity produced by cholinergic stimulation with carbamylcholine is not associated with alterations in cyclic AMP levels and is duplicated by 8-bromo-cyclic GMP. The effects of activators of adenylate cyclase, cholinomimetic agents, and 8-bromocyclic GMP are upon the attacking and not the target cells and occur at the time of initial interaction of attacking and target cells. Indeed, the level of cyclic nucleotide (cyclic AMP and cyclic GMP) at the time of initial cell-to-cell interaction determines the extent of cytotoxicity.


1975 ◽  
Vol 152 (3) ◽  
pp. 583-592 ◽  
Author(s):  
J Mowbray ◽  
J A Davies ◽  
D J Bates ◽  
C J Jones

Perfused rat heart incorporated L-[14C]tyrosine into protein at a constant rate for up to 75 min. A purified bovine growth-hormone preparation (1 mug/ml) stimulated the incorporation to a new constant rate that was more than three times the control rate by 10 min after hormone addition to perfusate. The hormone, however, did not alter the intracellular tracer amino acid pool, and the relationship of this to the aminoacyl-tRNA precursor pool is discussed. It is concluded that the increased incorporation largely reflected a rapid increase in protein synthesis at the ribosomes. Measurements of cyclic nucleotide contents during the perfusion showed that these appeared to vary in a systematic way during the perfusion. This strands in contrast with the constant values given by several other parameters measured in this preparation. Futher, the cyclic nucleotide variation seems to be independent of external effectors. The steady-state performance of the heart correlates more closely the [cyclic AMP]/[cyclic GMP] ratio than with the content of the individual cyclic nucleotides. At 10 min after the addition of growth hormone a slight decrese in cyclic AMP content and a large decrease in cyclic GMP were found, suggesting that the hormone's effect in stimulating protein synthesis may be mediated by a decrease in cyclic nucleotide concentrations or an increase in the [cyclic AMP]/[cyclic |p] ratio. The findings are also consistent with an intracellularly directed role for these nucleotides, and the possibility that the cyclic nucleotide changes are an indirect result of growth-hormone action is discussed.


1980 ◽  
Vol 87 (2) ◽  
pp. 336-345 ◽  
Author(s):  
C L Browne ◽  
A H Lockwood ◽  
J L Su ◽  
J A Beavo ◽  
A L Steiner

Cyclic nucleotides and cyclic nucleotide-dependent protein kinases have been implicated in the regulation of cell motility and division, processes that depend on the cell cytoskeleton. To determine whether cyclic nucleotides or their kinases are physically associated with the cytoskeleton during cell division, fluorescently labeled antibodies directed against cyclic AMP, cyclic GMP, and the cyclic nucleotide-dpendent protein kinases were used to localize these molecules in mitotic PtK1 cells. Both the cyclic GMP-dependent protein kinase and the type II regulatory subunit of the cyclic AMP-dependent protein kinase were localized on the mitotic spindle. Throughout mitosis, their distribution closely resembled that of tubulin. Antibodies to cyclic AMP, cyclic GMP, and the type I regulatory and catalytic subunits of the cyclic AMP-dependent protein kinase did not label the mitotic apparatus. The association between specific components of the cyclic neucleotide system and the mitotic spindle suggests that cyclic nucleotide-dependent phosphorylation of spindle proteins, such as those of microtubules, may play a fundamental role in the regulation of spindle assembly and chromosome motion.


1981 ◽  
Author(s):  
B Kiersnowska-Rogowska ◽  
M Bielawiec ◽  
F Rogowski ◽  
A Bodzenta ◽  
J Giedrojć

The aim of the work was to study plasma cyclic nucleotides level /cyclic-AMP and cyclic-GMP/ and platelet-leukocyte aggregates in patients with obliterative arteriosclerosis of the lower limbs. The following parameters were investigated: cyclic-AMP and GMP radioimmunochemically by the use of a cyclic-AMP and cyclic-GMP assay kit, platelet leukocyte aggregates by the method of Silbergleit in our modification.The remainder were hospital deaths, five within the first 48 hours, 8 between 2-14 days, and 4 between 14 and 94 days. Five cases showed subendocardial infarction (SI). Four of these occuring out of hospital. The remaining 18 cases were transmural infarctions (TI). Sixteen of 17 hospital deaths exhibited TI.Significant decrease in cyclic-AMP level was found in arteriosclerotic patients in comparison to the control group. No significant changes in cyclic-GMP level were observed. The number of platelet-leukocyte aggregates was significantly higher in these patients.The influence of Hydroxy-ethyl-rutosides /HR/ on investigated parameters was also studie.The significant decrease in the level of cyclic-GMP in plasma was observed in patients after intravenously injection of 1000 mg of HR whereas no changes were found in cyclic-AMP level. The significant decrease in the number of platelet-leukocytes aggregates in the blood obtained after HR injection was also observed.Our results have shown the disturbances of plasma cyclic nucleotides balance and function of platelets and leukocyte in arteriosclerotic patients. This study also suggests that HR may be a modulating agent of these parameters.


1975 ◽  
Vol 79 (1) ◽  
pp. 66-75 ◽  
Author(s):  
J. A. Fernandez-Pol ◽  
Marguerite T. Hays

ABSTRACT The effects of triiodothyronine (T3) on plasma and tissue levels (liver, adipose tissue, muscle) of adenosine 3′,5′-monophosphate (cyclic AMP) and guanosine 3′,5′-monophosphate (cyclic GMP) were determined in Mongrel dogs. Plasma cyclic AMP increased to a mean plateau value 165 % greater than control values in response to a single intravenous injection of T3 (100–200 μg/kg body weight). This treatment resulted in no increase in plasma cyclic GMP. In liver, cyclic AMP concentration decreased 54 %, while cyclic GMP increased 137 %. Adipose tissue cyclic AMP levels decreased in control animals during the experimental procedure. On the other hand, animals given T3 had stable or (in one case) increasing adipose tissue cyclic AMP levels. Hence, T3, actually maintained higher levels than that expected, in comparison to the control. Cyclic GMP levels in adipose tissue were not affected by T3. Cyclic AMP and cyclic GMP were unchanged in muscle. In all cases, a time lag occurred (30–40 min) between administration of T3 and subsequent alterations in cyclic nucleotide levels. It was concluded that T3 is capable of altering concentrations of cyclic AMP and cyclic GMP in vivo and that cyclic AMP and cyclic GMP patterns of response are completely different. In liver, a converse relation of the two nucleotides is present. These findings are compatible with the hypothesis that some of T3's action may be explained by its effects upon either cyclic AMP or cyclic GMP.


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