scholarly journals Distribution of 3':5'-cyclic AMP and 3':5'-cyclic GMP in rabbit retina in vivo: selective effects of dark and light adaptation and ischemia.

1976 ◽  
Vol 73 (12) ◽  
pp. 4442-4445 ◽  
Author(s):  
H. T. Orr ◽  
O. H. Lowry ◽  
A. I. Cohen ◽  
J. A. Ferrendelli
Keyword(s):  
Cyclic Amp ◽  
Cyclic Gmp ◽  
Light Adaptation ◽  
Rabbit Retina ◽  
Selective Effects

Possible role of cyclic GMP in stimulus-secretion coupling by salt gland of the duck

1979 ◽  
Vol 237 (5) ◽  
pp. C200-C204 ◽  
Author(s):  
D. J. Stewart ◽  
J. Sax ◽  
R. Funk ◽  
A. K. Sen
Keyword(s):  
Cyclic Amp ◽  
Guanylate Cyclase ◽  
Cyclic Gmp ◽  
Salt Gland ◽  
Domestic Ducks ◽  
Stimulus Secretion Coupling ◽  
Stimulation Of

Stimulation of salt galnd secretion in domestic ducks in vivo increased the cyclic GMP concentration of the tissue, but had no effect on cyclic AMP levels. Methacholine, which is known to stimulate sodium transport by the glands both in vivo and in vitro, stimulated ouabain-sensitive respiration in salt gland slices. Cyclic GMP stimulated ouabain-sensitive respiration to the same extent as methacholine. Guanylate cyclase stimulators, hydroxylamine and sodium azide, also stimulated ouabain-sensitive respiration. The stimulation of ouabain-sensitive respiration by methacholine was blocked either by atropine or by removal of calcium from the incubation medium. The stimulation of ouabain-sensitive respiration by cyclic GMP still occurred in the absence of calcium. The above observations seem to indicate that cyclic GMP acts as a tertiary link in the process of stimulus-secretion coupling in the tissue.

ALTERATIONS IN CYCLIC NUCLEOTIDES IN DOGS AFTER TRIIODOTHYRONINE

1975 ◽  
Vol 79 (1) ◽  
pp. 66-75 ◽  
Author(s):  
J. A. Fernandez-Pol ◽  
Marguerite T. Hays
Keyword(s):  
Adipose Tissue ◽  
Cyclic Amp ◽  
Cyclic Gmp ◽  
Cyclic Nucleotides ◽  
Time Lag ◽  
The Other ◽  
Experimental Procedure ◽  
Single Intravenous Injection ◽  
Converse Relation

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.

Cyclic Nucleotides in Epileptic Brain: Effects of Pentylenetetrazol on Regional Cyclic AMP and Cyclic GMP Levels In Vivo

Epilepsia ◽  
1977 ◽  
Vol 18 (4) ◽  
pp. 525-531 ◽  
Author(s):  
James A. Ferrendelli ◽  
Dorothy A. Kinscherf
Keyword(s):  
Cyclic Amp ◽  
Cyclic Gmp ◽  
Cyclic Nucleotides

Pyrophosphate-induced inflammation: An in vivo study of the interrelationship of intracellular cyclic AMP and cyclic GMP

1976 ◽  
Vol 6 (4) ◽  
pp. 476-478 ◽  
Author(s):  
D. A. Deporter ◽  
P. Dieppe ◽  
D. A. Willoughby
Keyword(s):  
Cyclic Amp ◽  
Cyclic Gmp ◽  
In Vivo Study

scholarly journals Purification and kinetic properties of two soluble forms of calmodulin-dependent cyclic nucleotide phosphodiesterase from rat pancreas

1983 ◽  
Vol 211 (2) ◽  
pp. 341-347 ◽  
Author(s):  
A Vandermeers ◽  
M C Vandermeers-Piret ◽  
J Rathe ◽  
J Christophe
Keyword(s):  
Cyclic Amp ◽  
Affinity Chromatography ◽  
Cyclic Gmp ◽  
High Performance ◽  
Minor Component ◽  
Fold Increase ◽  
Kinetic Properties ◽  
Maximal Velocity ◽  
Rat Pancreas

The calmodulin-dependent cyclic AMP phosphodiesterase and cyclic GMP phosphodiesterase (EC 3.1.4.17) activity of rat pancreas was purified 280-fold by affinity chromatography on calmodulin-Sepharose 4B. It then accounted for 15% of the total cytosol cyclic GMP nucleotide phosphodiesterase activity, in the presence of Ca2+, and represented a minor component of proteins specifically adsorbed by the column. This activity was resolved on a DEAE-Sephacel column into two fractions, termed PI and PII, on the basis of their order of emergence. After this step, PI and PII were purified 5650- and 3700-fold respectively. The molecular weight of PI was 175 000 and that of PII was 116 000, by polyacrylamide-gradient-gel electrophoresis. Both forms of phosphodiesterase could hydrolyse cyclic AMP and cyclic GMP, although PII displayed a higher affinity toward cyclic GMP than toward cyclic AMP. PI and PII exhibited negative homotropic kinetics in the absence of calmodulin. Upon addition of calmodulin, both enzymes displayed Michaelis-Menten kinetics and a 5-9-fold increase in maximal velocity, at physiological concentrations of cyclic GMP and cyclic AMP. When a pancreatic extract freshly purified by affinity chromatography was immediately analysed by high-performance gel-permeation chromatography on a TSK gel G3000 SW column, PII represented as much as 78% of the eluted activity. This percentage decreased to 52% when the sample was stored at 0 degrees C for 20 h before analysis, suggesting that PII, possibly predominant in vivo, was converted into the heavier PI form upon storage.

MODIFICATION OF MYOMETRIAL ACTIVITY IN VIVO BY ADMINISTRATION OF CYCLIC NUCLEOTIDES AND THEOPHYLLINE TO THE PREGNANT RAT

1975 ◽  
Vol 66 (3) ◽  
pp. 339-347 ◽  
Author(s):  
J. W. BUCKLE ◽  
P. W. NATHANIELSZ
Keyword(s):  
Cyclic Amp ◽  
Cyclic Gmp ◽  
Cyclic Nucleotides ◽  
Dibutyryl Cyclic Amp ◽  
Short Term ◽  
Pregnant Rats ◽  
Pregnant Rat ◽  
Uterine Activity ◽  
Prostaglandin F

SUMMARY Myometrial activity was recorded in vivo in unrestrained pregnant rats from day 19 of gestation using radiotelemetry. The effects of short-term infusions of theophylline, dibutyryl cyclic AMP and 8-bromo-cyclic GMP were investigated. All three compounds caused a decrease in oxytocin-induced, prostaglandin F2α-induced and spontaneous uterine activity. After cessation of the infusion of these compounds uterine activity returned to near pre-infusion levels within approximately 15 min in most animals. The possible roles of cyclic nucleotides in the control of myometrial contraction are discussed in the light of these observations.

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