scholarly journals Deoxyribonucleic acid and polyamine synthesis in rat ventral prostate. Effects of age of the intact rat and androgen stimulation of the castrated rat with testosterone, 5α-dihydrotestosterone and 5α-androstane-3β, 17β-diol

1977 ◽  
Vol 162 (1) ◽  
pp. 87-97 ◽  
Author(s):  
E E K Takyi ◽  
D J M Fuller ◽  
L J Donaldson ◽  
G H Thomas
Keyword(s):  
Ornithine Decarboxylase ◽  
Ventral Prostate ◽  
Molar Ratio ◽  
Synthetic Activity ◽  
Decarboxylase Activity ◽  
Polyamine Synthesis ◽  
Molar Ratios ◽  
Ornithine Decarboxylase Activity ◽  
The Relationship

The relationship between polyamine synthesis, growth and secretion in vivo was examined in ventral prostates from: (a) intact rats aged 3-60 weeks; (b) animals castrated for 7 days before injection with 5 alpha-dihydrotestosterone (17 beta-hydroxy-5-alpha-androstan-3-one), testosterone and 5 alpha-androstane-3 beta, 17 beta-diol for up to 10 days; (c) rats injected with the 3 beta, 17 beta-diol immediately after castration. Ornithine decarboxylase activity and the concentrations of putrescine, spermidine and spermine were measured. DNA-synthetic activity was monitored by measuring [125I]iododoxyuridine incorporation. An enhanced spermidine/spermine molar ratio reflected increased activity of the prostate. The ratio was higher (greater than 2) in prostates from sexually immature animals, than in the intact adult (1.5), suggesting that the ratio was indicative of the proliferative activity of the tissue. However, in the androgen-stimulated castrated rat, enhanced spermidine/spermine ratios tended to correlate with hypertrophy and secretion. In both sets of experiments there was a linear relationship between protein and spermidine content. High spermidine/spermine molar ratios were the consequence of a relatively low rate of accumulation of spermine relative to spermidine and protein. The relationship between polyamine synthesis and DNA-synthetic activity was investigated in cultured prostate. A combination of insulin (3 mug/ml) and testosterone (0.1 muM caused a stimulatory response in the incorporation of [125I]iododeoxyuridine and in cell division, despite a depleted polyamine content and low ornithine decarboxylase activity in the cultured tissue.

scholarly journals Polyamine synthesis in bone marrow granulocytes: effect of cell maturity and early changes following an inflammatory stimulus

Blood ◽  
1978 ◽  
Vol 51 (6) ◽  
pp. 1021-1029
Author(s):  
WH Evans ◽  
CK Grieshaber ◽  
WC Miller ◽  
SM Wilson ◽  
HA Hoffman
Keyword(s):  
Bone Marrow ◽  
Ornithine Decarboxylase ◽  
Synthetic Activity ◽  
Neutrophil Granulocytes ◽  
Decarboxylase Activity ◽  
Inflammatory Stimulus ◽  
Maximum Increase ◽  
Polyamine Synthesis ◽  
Ornithine Decarboxylase Activity ◽  
Bone Marrow Granulocytes

Enriched fractions of mature and immature neutrophil granulocytes, isolated from guinea pig bone marrow, were assayed for ornithine decarboxylase activity and polyamine content. The results show that immature granulocytes contain at least ten times more ornithine decarboxylase activity and two times more spermidine than mature granulocytes. The incorporation of 14C-ornithine into putrescine and spermidine of intact immature granulocytes was three to four times and ten times, respectively, that of mature granulocyte preparations. Six hours after an inflammatory stimulus, transient increases of 14-fold and 3-fold in the activities of ornithine decarboxylase and S-adenosyl- L-methionine decarboxylase, respectively, were observed in immature bone marrow granulocytes. At this time the incorporation of 14C- ornithine into putrescine and spermidine in bone marrow granulocytes from stimulated animals was 14 times that of cells from controls. A maximum increase in DNA synthesis in these cells during the inflammatory response occurred 6 hr after the maximum increase in the polyamine synthetic activity. Together these data suggest that polyamine synthesis in the granulocyte compartment of the bone marrow is associated chiefly with immature proliferating cells and that increased polyamine synthesis precedes increased granulocyte proliferation in the bone marrow following an inflammatory stimulus.

scholarly journals Polyamine synthesis in bone marrow granulocytes: effect of cell maturity and early changes following an inflammatory stimulus

Blood ◽  
1978 ◽  
Vol 51 (6) ◽  
pp. 1021-1029 ◽  
Author(s):  
WH Evans ◽  
CK Grieshaber ◽  
WC Miller ◽  
SM Wilson ◽  
HA Hoffman
Keyword(s):  
Bone Marrow ◽  
Ornithine Decarboxylase ◽  
Synthetic Activity ◽  
Neutrophil Granulocytes ◽  
Decarboxylase Activity ◽  
Inflammatory Stimulus ◽  
Maximum Increase ◽  
Polyamine Synthesis ◽  
Ornithine Decarboxylase Activity ◽  
Bone Marrow Granulocytes

Abstract Enriched fractions of mature and immature neutrophil granulocytes, isolated from guinea pig bone marrow, were assayed for ornithine decarboxylase activity and polyamine content. The results show that immature granulocytes contain at least ten times more ornithine decarboxylase activity and two times more spermidine than mature granulocytes. The incorporation of 14C-ornithine into putrescine and spermidine of intact immature granulocytes was three to four times and ten times, respectively, that of mature granulocyte preparations. Six hours after an inflammatory stimulus, transient increases of 14-fold and 3-fold in the activities of ornithine decarboxylase and S-adenosyl- L-methionine decarboxylase, respectively, were observed in immature bone marrow granulocytes. At this time the incorporation of 14C- ornithine into putrescine and spermidine in bone marrow granulocytes from stimulated animals was 14 times that of cells from controls. A maximum increase in DNA synthesis in these cells during the inflammatory response occurred 6 hr after the maximum increase in the polyamine synthetic activity. Together these data suggest that polyamine synthesis in the granulocyte compartment of the bone marrow is associated chiefly with immature proliferating cells and that increased polyamine synthesis precedes increased granulocyte proliferation in the bone marrow following an inflammatory stimulus.

scholarly journals Ornithine decarboxylase activity and: [125I]iododeoxyuridine incorporation in rat prostate

1975 ◽  
Vol 150 (3) ◽  
pp. 557-559 ◽  
Author(s):  
D J Fuller ◽  
L J Donaldson ◽  
G H Thomas
Keyword(s):  
Ornithine Decarboxylase ◽  
Secretory Activity ◽  
Ventral Prostate ◽  
Decarboxylase Activity ◽  
Ornithine Decarboxylase Activity ◽  
Rat Prostate ◽  
The Relationship

The relationship between ornithine decarboxylase activity and [125I]iododexyuridine incorporation was studied in prostates from castrated rats (aged 5, 26 and 80 weeks) injected daily with testosterone for up to 10 days. The results suggest that ornithine decarboxylase activity is a parameter of secretory activity, rather than growth, in the ventral prostate. In the dorsolateral prostate, ornithine decarboxylase activity tends to parallel [125I]iododeoxyuridine incorporation.

scholarly journals Role of pyridoxal phosphate in mammalian polyamine biosynthesis. Lack of requirement for mammalian S-adenosylmethionine decarboxylase activity

1977 ◽  
Vol 166 (1) ◽  
pp. 81-88 ◽  
Author(s):  
A E Pegg
Keyword(s):  
Ornithine Decarboxylase ◽  
Pyridoxal Phosphate ◽  
Vitamin B ◽  
Decarboxylase Activity ◽  
Deficient Diet ◽  
Polyamine Biosynthesis ◽  
Adenosylmethionine Decarboxylase ◽  
Ornithine Decarboxylase Activity

1. Polyamine concentrations were decreased in rats fed on a diet deficient in vitamin B-6. 2. Ornithine decarboxylase activity was decreased by vitamin B-6 deficiency when assayed in tissue extracts without addition of pyridoxal phosphate, but was greater than in control extracts when pyridoxal phosphate was present in saturating amounts. 3. In contrast, the activity of S-adenosylmethionine decarboxylase was not enhanced by pyridoxal phosphate addition even when dialysed extracts were prepared from tissues of young rats suckled by mothers fed on the vitamin B-6-deficient diet. 4. S-Adenosylmethionine decarboxylase activities were increased by administration of methylglyoxal bis(guanylhydrazone) (1,1′-[(methylethanediylidine)dinitrilo]diguanidine) to similar extents in both control and vitamin B-6-deficient animals. 5. The spectrum of highly purified liver S-adenosylmethionine decarboxylase did not indicate the presence of pyridoxal phosphate. After inactivation of the enzyme by reaction with NaB3H4, radioactivity was incorporated into the enzyme, but was not present as a reduced derivative of pyridoxal phosphate. 6. It is concluded that the decreased concentrations of polyamines in rats fed on a diet containing vitamin B-6 may be due to decreased activity or ornithine decarboxylase or may be caused by an unknown mechanism responding to growth retardation produced by the vitamin deficiency. In either case, measurements of S-adenosylmethionine decarboxylase and ornithine decarboxylase activity under optimum conditions in vitro do not correlate with the polyamine concentrations in vivo.

scholarly journals Dissociation of tumour-promoter-induced effects on prostaglandin release, polyamine synthesis and cell proliferation of 3T3 cells

1981 ◽  
Vol 194 (3) ◽  
pp. 975-982 ◽  
Author(s):  
R Lanz ◽  
K Brune
Keyword(s):  
Cell Proliferation ◽  
Ornithine Decarboxylase ◽  
Thymidine Incorporation ◽  
Decarboxylase Activity ◽  
3T3 Cells ◽  
Polyamine Synthesis ◽  
Ornithine Decarboxylase Activity ◽  
Proliferative Effect ◽  
Prostaglandin Release ◽  
Anti Inflammatory

The phorbol ester 12-O-tetradecanoylphorbol 13-acetate induces tumour promotion, inflammation, cell proliferation and prostaglandin release. Recent reports suggest that the prostaglandins released by 12-O-tetradecanoylphorbol 13-acetate (TPA) initiate a cascade of events leading to polyamine synthesis and cell proliferation. In experiments designed to test this contention, it was found that addition of TPA (1 microM to 1 nM) to confluent mouse 3T3 fibroblasts successively caused the release of prostaglandins E2 and I2, induction of the enzyme ornithine decarboxylase (EC 4.1.1.17), stimulation of [3H]thymidine incorporation into DNA, and cell proliferation. Pretreatment of the cells with the anti-inflammatory steroid dexamethasone (1 microM) or the non-steroidal anti-inflammatory drug indomethacin (1 microM) inhibited TPA-induced prostaglandin release. However, dexamethasone enhanced the other effects of TPA, whereas indomethacin was ineffective. Addition of prostaglandin E2 to the cultures did not induce ornithine decarboxylase activity and cell proliferation. Pretreatment of the cells with 1,3-diaminopropane (1 mM) or alpha-methylornithine (5 mM), inhibitors of polyamine synthesis, decreased TPA-induced ornithine decarboxylase activity without affecting DNA synthesis. TPA stimulated [3H]thymidine incorporation into DNA, even when the ornithine decarboxylase activity was completely blocked. These data suggest that the proliferative effect of TPA on 3T3 cells is independent of prostaglandin release and polyamine synthesis.

scholarly journals Diamine-induced inhibition of liver ornithine decarboxylase

1979 ◽  
Vol 177 (1) ◽  
pp. 63-69 ◽  
Author(s):  
Arja Kallio ◽  
Monica Löfman ◽  
Hannu Pösö ◽  
Juhani Jänne
Keyword(s):  
Enzyme Activity ◽  
Ornithine Decarboxylase ◽  
Enzyme Inhibitor ◽  
Decarboxylase Activity ◽  
Enzyme Protein ◽  
Intracellular Degradation ◽  
Ornithine Decarboxylase Activity ◽  
Normal Rat

Re!peated injections of 1,3-diaminopropane, a potent inhibitor of mammalian ornithine decarboxylase, induced protein-synthesis-dependent formation of macromolecular inhibitors or ‘antienzymes’ [Heller, Fong & Canellakis (1976) Proc. Natl. Acad. Sci. U.S.A.73, 1858–1862] to ornithine decarboxylase in normal rat liver. Addition of the macromolecular inhibitors, produced in response to repeated injections of diaminopropane, to active ornithine decarboxylase in vitro resulted in a profound loss of the enzyme activity, which, however, could be partly recovered after passage of the enzyme–inhibitor mixture through a Sephadex G-75 columin in the presence of 0.4m-NaCl. This treatment also resulted in the appearance of free inhibitor. In contrast with the separation of the enzyme and inhibitory activity after combination in vitro, it was not possible to re-activate, by using identical conditions of molecular sieving, any inhibited ornithine decarboxylase from cytosol fractions obtained from animals injected with diaminopropane. However, the idea that injection of various diamines, also in vivo, induces acute formation of macromolecular inhibitors, which reversibly combine with the enzyme, was supported by the finding that the ornithine decarboxylase activity remaining after diaminopropane injection appeared to be more stable to increased ionic strength than the enzyme activity obtained from somatotropin-treated rats. Incubation of the inhibitory cytosol fractions with antiserum to ornithine decarboxylase did not completely abolish the inhibitory action of either the cytosolic inhibitor or the antibody. A single injection of diaminopropane produced an extremely rapid decay of liver ornithine decarboxylase activity (half-life about 12min), which was comparable with, or swifter than, that induced by cycloheximide. However, although after cycloheximide treatment the amount of immunotitrable ornithine decarboxylase decreased only slightly more slowly than the enzyme activity, diaminopropane injection did not decrease the amount of the immunoreactive protein, but, on the contrary, invariably caused a marked increase in the apparent amount of antigen, after some lag period. The diamine-induced increase in the amount of the immunoreactive enzyme protein could be totally prevented by a simultaneous injection of cycloheximide. These results are in accord with the hypothesis that various diamines may result in rapid formation of macromolecular inhibitors to ornithine decarboxylase in vivo, which, after combination with the enzyme, abolish the catalytic activity but at the same time prevent the intracellular degradation of the enzyme protein.

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