Changes in Plasma Cyclic AMP and Cyclic GMP during Spontaneous Labor and Labor Induced by Oxytocin, Prostaglandin F2α and Prostaglandin E2

1988 ◽  
Vol 26 (1) ◽  
pp. 21-28 ◽  
Author(s):  
Ichiro Nagata ◽  
Kenichi Furuya ◽  
Eiji Imaizumi ◽  
Katsuyoshi Seki ◽  
Noriko Makimura ◽  
...  
Keyword(s):  
Cyclic Amp ◽  
Cyclic Gmp ◽  
Prostaglandin E ◽  
Prostaglandin F

Follicle-stimulating hormone-induced prostaglandin E formation in isolated rat ovarian theca

1983 ◽  
Vol 97 (1) ◽  
pp. 43-49 ◽  
Author(s):  
U. Zor ◽  
B. Strulovici ◽  
R. Braw ◽  
H. R. Lindner ◽  
A. Tsafriri
Keyword(s):  
Cyclic Amp ◽  
Cyclic Gmp ◽  
Follicle Stimulating Hormone ◽  
Fold Increase ◽  
Prostaglandin E ◽  
Β Subunit ◽  
Biochemical Effects ◽  
Isolated Rat ◽  
Stimulating Hormone

The aim of this study was to search for direct biochemical effects of highly purified FSH on isolated ovarian follicular theca in vitro. Granulosa cells (GC; approximately 1 × 105 cells per follicle) were flushed from isolated follicles of pro-oestrous rats. The remaining theca layer and the isolated GC were incubated with highly purified ovine FSH. Prostaglandin E (PGE) accumulation was measured by radioimmunoassay. Follicle-stimulating hormone induced a 15-fold increase in PGE accumulation over the basal level in the follicular theca, the stimulated rate exceeding threefold that observed in the GC fraction derived from the same follicle. Follicle-stimulating hormone caused no significant increase in cyclic AMP level or steroidogenesis in the theca layer, but was active on these parameters in the GC. In contrast, LH increased the accumulation of cyclic AMP, progesterone and testosterone, as well as of PGE, in follicular theca. Exogenous 8-bromo cyclic AMP or cyclic GMP also stimulated PGE production in follicular theca or GC, but FSH was without any effect on the level of endogenous cyclic GMP in GC or follicular theca. Antibodies to FSH prevented the effect of FSH (but not that of LH) on PGE formation by follicular theca and GC, while antibodies to the β-subunit of LH blocked the effect of LH but not of FSH. We conclude that highly purified FSH has a stimulatory effect on PGE formation by the follicular theca.

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.

scholarly journals Cardiac effects of prostaglandins E1 and F1α

1981 ◽  
Vol 59 (5) ◽  
pp. 473-478 ◽  
Author(s):  
Rao V. S. V. Vadlamudi ◽  
John H. McNheill
Keyword(s):  
Cyclic Amp ◽  
Cyclic Nucleotide ◽  
Left Atrial ◽  
Contractile Force ◽  
Right Atrial ◽  
Prostaglandin E ◽  
Tension Development ◽  
Prostaglandin F ◽  
Perfused Hearts ◽  
Dose Dependent

The effects of prostaglandin E1 (PGE1) and prostaglandin F1α (PGF1α) were studied on perfused rat hearts and isolated rat atria. Both PGE1 and PGF1α produced dose-dependent increases in right atrial rate but had no effect on left atrial tension development. PGE1 (10−4 M) increased right atrial cyclic AMP content without changing phosphorylase a activity. PGF1α (10−4 M) did not change right atrial cyclic AMP or cyclic GMP content. Both prostaglandins had no effect on left atrial cyclic nucleotide content. When infused at a rate of 1 μg/min, PGE1 produced a time-dependent increase in cyclic AMP content in the Langendorff perfused hearts but did not alter contractile force development or phosphorylase a activity. An infusion of PGF1α produced a dose-dependent increase in tension development which was secondary to a negative chronotropic effect. PGF1α (1 μg/min) did not produce any changes in cyclic nucleotide levels or phosphorylase a activity in the Langendorff perfused hearts. These results show that PGE1 can selectively increase myocardial cyclic AMP content without altering contractile force or phosphorylase activity and that PGF1α does not increase rat cardiac AMP levels.

Effect of Cyclic AMP and Cyclic GMP on Thromboplastin (Factor III) Synthesis in Human Monocytes In Vitro

1983 ◽  
Vol 50 (04) ◽  
pp. 804-809 ◽  
Author(s):  
Torstein Lyberg
Keyword(s):  
Cyclic Amp ◽  
Cyclic Gmp ◽  
Immune Complexes ◽  
Phosphodiesterase Inhibitors ◽  
Inhibitory Effect ◽  
Intracellular Camp ◽  
Human Monocytes ◽  
Purified Protein Derivative ◽  
A 23187

SummaryHuman monocytes in vitro respond to various agents (immune complexes, lectins, endotoxin, the divalent ionophore A 23187, 12-0-tetradecanoyl-phorbol 13-acetate [TPA], purified protein derivative [PPD] of Bacille Calmette-Guerin) with an increased synthesis of the protein component of thromboplastin. The effect of cyclic AMP and cyclic GMP on this response has been studied. Dibutyryl-cyclic AMP, prostaglandin E1 and the phosphodiesterase inhibitors 3-butyl-1-methyl-xanthine (MIX) and rac -4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone (Ro 201724), separately and in combination have a pronounced inhibitory effect on the response to immune complexes and PPD, and a moderate effect on the response to endotoxin and lectins. The effect on TPA response and on the response to A 23187 was slight. Dibutyryl-cyclic GMP (1 mM) gave a slight inhibition of the TPA arid IC response, but had essentially no effect on the response to other inducers. The intracellular cAMP level increased when monocytes were incubated with IC, TPA or A 23187 followed by a decrease to basal levels within 1-2 hr, whereas lectin (PHA) and PPD did not induce such changes. The cAMP response to endotoxin varied. Stimulation with IC induced an increase in monocyte cGMP levels, whereas the other stimulants did not cause such changes.

Interaction between parathyroid hormone and prostaglandin E1 on cyclic AMP metabolism in rat kidney

1980 ◽  
Vol 93 (3) ◽  
pp. 339-345 ◽  
Author(s):  
Naokazu Nagata ◽  
Yuriko Ono ◽  
Narimichi Kimura
Keyword(s):  
Parathyroid Hormone ◽  
Cyclic Amp ◽  
Adenylate Cyclase ◽  
Rat Kidney ◽  
Prostaglandin E ◽  
Cortical Tissue ◽  
Newborn Rat ◽  
Simultaneous Addition ◽  
Renal Cortical Tissue ◽  
Subsequent Addition

Abstract. The interaction between parathyroid hormone (PTH) and prostaglandin E1 (PGE1) in influencing cyclic AMP metabolism in rat renal cortical tissue was examined. PTH and PGE1 stimulated additively the adenylate cyclase activity in the homogenate of the tissue. Both PTH and PGE1 enhanced the level of cyclic AMP in the incubated renal cortical tissue, but the effect of their simultaneous addition did not exceed the effect induced by PTH alone. Cyclic AMP accumulated in the incubation medium by stimulation by PTH was decreased by the simultaneous addition of PGE1. When the tissue was pre-incubated for 30 min with 2 to 10 μg/ml of PGE1, the magnitude of the increase of cyclic AMP caused by PTH subsequently added was lessened. However, the response to PTH of adenylate cyclase preparation obtained from the homogenate of PGE1-pre-treated tissue was not decreased. When first PTH was added to the incubating renal cortical tissue, the subsequent addition of PGE1 accelerated the decrease of cyclic AMP content in the tissue and decreased the amount of cyclic AMP released from the tissue. The interaction of PTH and PGE1 on cyclic AMP metabolism in the renal cortical tissue was in contrast to that seen in newborn rat calvaria where PGE1 and PTH acted additively in enhancing the level of cyclic AMP.

scholarly journals Cellular localization of cyclic AMP and cyclic GMP in rat bone marrow

1979 ◽  
Vol 29 ◽  
pp. 85
Author(s):  
Nobuyoshi Yoshida ◽  
Kohtaro Taniyama ◽  
Chikako Tanaka
Keyword(s):  
Bone Marrow ◽  
Cyclic Amp ◽  
Cyclic Gmp ◽  
Cellular Localization ◽  
Rat Bone

Melanocyte-stimulating hormone and the regulation of tyrosinase activity in hair follicular melanocytes of the mouse

1986 ◽  
Vol 111 (2) ◽  
pp. 225-232 ◽  
Author(s):  
S. A. Burchill ◽  
A. J. Thody
Keyword(s):  
Cyclic Amp ◽  
Cyclic Gmp ◽  
Hair Growth ◽  
Yellow Pigment ◽  
Tyrosinase Activity ◽  
Melanocyte Stimulating Hormone ◽  
Golden Yellow ◽  
Skin Explants ◽  
Low Levels ◽  
Old Mice

ABSTRACT Skin tyrosinase activity increases during hair growth in C3H–HeA*vy mice and reaches higher levels in young (30- to 35-day-old) mice when the hair follicular melanocytes synthesize the black pigment, eumelanin, than in older (6-month-old) mice when they produce the golden yellow pigment, phaeomelanin. To examine the regulation of the melanocytes at these different stages we have compared the effect of α-MSH and other agents that act, through cyclic AMP-dependent mechanisms, on skin tyrosinase activity in both young and old mice during hair growth, initiated by plucking. Daily administration of α-MSH, isoprenaline or theophylline increased coat darkness, and skin tyrosinase activity in the younger mice 7–9 days after plucking, but they were ineffective in the older mice. Similarly α-MSH, 8-bromo-cyclic AMP or theophylline increased tyrosinase activity in skin explants from the younger mice incubated for up to 24 h but had no effect in explants from older mice. Cyclic GMP had no effect on tyrosinase activity in skin explants from both young and old mice. It is suggested that whereas cyclic AMP-dependent mechanisms may operate to regulate tyrosinase activity in the hair follicular melanocytes of younger mice that produce eumelanin these systems may not operate in the older mice when these melanocytes synthesize phaeomelanin. Phaeomelanin synthesis, unlike that of eumelanin, may not depend upon tyrosinase and its regulation by cyclic AMP and this could explain the low levels of this enzyme in the skin and its failure to respond to α-MSH and other activators of the cyclic AMP system during periods of phaeomelanin production. J. Endocr. (1986) 111, 225–232

scholarly journals Accumulation of Prostacyclin in Rat Brain during Haemorrhagic Hypotension—Possible Role of PGI2 in Autoregulation

1984 ◽  
Vol 4 (1) ◽  
pp. 107-109 ◽  
Author(s):  
E. Shohami ◽  
A. Sidi
Keyword(s):  
Blood Pressure ◽  
Steady State ◽  
Control Group ◽  
Prostaglandin E ◽  
Cortical Tissue ◽  
Arterial Blood ◽  
Haemorrhagic Hypotension ◽  
Potent Vasodilator ◽  
Prostaglandin F

The effect of haemorrhagic hypotension on the levels of prostaglandin E2 (PGE2), thromboxane B2 (TXB2), and 6-keto prostaglandin F1α (6-keto-PGF1α) in cortical tissue of rats was studied. Lightly anesthetized rats were subjected to steady-state hypotension for 15 min, with a mean arterial blood pressure of 80, 60, and 40 mm Hg, and compared to a control group of normotensive rats. No significant change was found in the levels of PGE2 and TXB2. The level of 6-keto-PGF1α increased from 7.8 ± 0.9 to 14.1 ± 1.9 pg/mg protein (p < 0.02) at 80 mm Hg. Our findings suggest that prostacyclin, which is a potent vasodilator, might play a role in setting the lower limit of the autoregulation range.

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