Evidence for the presence of cyclic adenosine 3′,5′-monophosphate and its metabolism in loblolly pine (Pinustaeda L.) callus

Evidence is presented suggesting the occurrence of cyclic adenosine 3′,5′-monophosphate (cAMP) and adenyl cyclase activity in loblolly pine (Pinustaeda L.) callus cultures grown aseptically on a defined medium. The presence of enzymes in the callus capable of catalyzing cAMP hydrolysis also was detected. Adenosine was the most stable product resulting from cAMP hydrolysis. A direct relationship was found between apparent cAMP concentration and the rate of fresh weight increase of dark-grown callus during a 6-week passage.

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Restrained Adenyl Cyclase in Human Neutrophils: Stimulation of Cyclic Adenosine 3':5'-Monophosphate Formation and Adenyl Cyclase Activity by Phagocytosis and Prostaglandins

Blood ◽

10.1182/blood.v43.5.743.743 ◽

1974 ◽

Vol 43 (5) ◽

pp. 743-748 ◽

Cited By ~ 6

Author(s):

Viktor Stolc

Keyword(s):

Human Lymphocytes ◽

Adenyl Cyclase ◽

Camp Level ◽

Human Neutrophils ◽

Camp Concentration ◽

Additional Increase ◽

Stimulatory Action ◽

Adenyl Cyclase Activity ◽

Latex Particles ◽

Camp System

Abstract We observed that prostuglandins (PG) E1, E2, A1, A2, B1, and F2 alpha increase cAMP concentration in resting neutrophils. In phagocytosing cells, an additional enhancement was seen with PG E1 and PG A2. Such a stimulatory effect of Pg E1 was noted any time during phagocytosis of latex microparticles (3-18 min). Adrenergic inhibitors, phentolamine and propranolol, did not interfere with the stimulatory action of PG E1 on cAMP level in resting and phagocytosing leukocytes. Both aforementioned inhibitors enhanced cAMP level in resting and phagocytosing neutrophils at 1 mM concentration, and an additional increase was seen in PG E1stimulated leukocytes. Although phosphodiesterase activity was unchanged by phagocytosis and PG E1 action, adenylate cyclase (AC) activity was significantly higher in neutrophil homogenates after phagocytosis of latex particles. In contrary, contact of human lymphocytes with latex particles revealed a decrease in AC activity. These data indicate that AC-cAMP system is partly in a restrained state in resting neutrophils and can be relieved by phagocytosis.

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Dependence of Platelet Adenyl Cyclase System on Oxidative Phosphorylation

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651444 ◽

1975 ◽

Vol 34 (01) ◽

pp. 042-049 ◽

Cited By ~ 1

Author(s):

Shuichi Hashimoto ◽

Sachiko Shibata ◽

Bokro Kobayashi

Keyword(s):

Cyclic Amp ◽

Oxidative Phosphorylation ◽

Sodium Succinate ◽

Potassium Cyanide ◽

Adenyl Cyclase ◽

Mitochondrial Oxidative Phosphorylation ◽

Adenyl Cyclase Activity ◽

Intact Rabbit ◽

Adenyl Cyclase System ◽

Cyclic Amp Synthesis

SummaryThe radioactive adenosine 3′,5′-monophosphate (cyclic AMP) level derived from 8-14C adenine in intact rabbit platelets decreased in the presence of mitochondrial inhibitor (potassium cyanide) or uncoupler (sodium azide), and markedly increased by the addition of NaF, monoiodoacetic acid (MIA), or 2-deoxy-D-glucose. The stimulative effect of the glycolytic inhibitors was distinctly enhanced by the simultaneous addition of sodium succinate. MIA did neither directly stimulate the adenyl cyclase activity nor inhibit the phosphodiesterase activity. These results suggest that cyclic AMP synthesis in platelets is closely linked to mitochondrial oxidative phosphorylation.

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Proceedings: The effects of exogenous gonadotrophins on ovarian adenyl cyclase activity

Reproduction ◽

10.1530/jrf.0.0360445 ◽

1974 ◽

Vol 36 (2) ◽

pp. 445-446

Author(s):

C. Nugent ◽

A Lopata ◽

M. Gould

Keyword(s):

Adenyl Cyclase ◽

Cyclase Activity ◽

Adenyl Cyclase Activity

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Studies on Inhibition of TSH Stimulation of Adenyl Cyclase Activity in Thyroid Plasma Membrane Preparations by Propranolol

Endocrinology ◽

10.1210/endo-96-6-1513 ◽

1975 ◽

Vol 96 (6) ◽

pp. 1513-1519 ◽

Cited By ~ 20

Author(s):

NICHOLAS J. MARSHALL ◽

SIGRID VON BORCKE ◽

P. GORDON MALAN

Keyword(s):

Plasma Membrane ◽

Adenyl Cyclase ◽

Cyclase Activity ◽

Adenyl Cyclase Activity ◽

Tsh Stimulation ◽

Stimulation Of

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CYTOCHEMICAL LOCALIZATION OF ADENYL CYCLASE ACTIVITY IN RAT ISLETS OF LANGERHANS

Journal of Histochemistry & Cytochemistry ◽

10.1177/20.11.873 ◽

1972 ◽

Vol 20 (11) ◽

pp. 873-879 ◽

Cited By ~ 119

Author(s):

S. L. HOWELL ◽

MARGARET WHITFIELD

Keyword(s):

B Cells ◽

Islets Of Langerhans ◽

Adenosine Triphosphate ◽

Adenyl Cyclase ◽

Cyclase Activity ◽

Cytochemical Localization ◽

Adenyl Cyclase Activity ◽

Rat Islets ◽

Rat Islets Of Langerhans ◽

A And B Cells

A cytochemical method has been used to investigate the localization of adenyl cyclase activity in A and B cells of isolated rat islets of Langerhans. Adenosine triphosphate was initially utilized as substrate, the pyrophosphate liberated being precipitated by lead ions at its site of production. The specificity of the method was increased by the use of adenylyl-imidodiphosphate as an alternative substrate; this adenosine triphosphate analogue was not hydrolyzed by adenosine triphosphatase but provided an effective substrate for adenyl cyclase. Adenyl cyclase activity, which was found to retain its glucagon and fluoride sensitivity in glutaraldehyde-fixed tissue, was found exclusively and almost uniformly in the plasma membranes of A and B cells. Storage granule membrane, incorporated into the plasma membrane during secretion of the granule content by exocytosis, appeared to be devoid of adenyl cyclase activity.

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