Estrogen Increases Hypothalamic and Pituitary Polyamine Levels in Ovariectomized Rats

Gray, Heewon L.; Jasper, Thomas W.; Luttge, William G.; Shukla, Jayesh B.; Rennert, Owen M.

doi:10.1111/j.1471-4159.1980.tb11210.x

Cited by 9 publications

(5 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As in nonneural tissues, ODC activity in the brain appears to be regulated by steroid hormones (Gray et al, 1980;Cousin et al, 1982), and the present results show that ODC and SAT, but not SAMDC, activities in the hippocampus, cerebellar cortex, vermis, and deep nuclei are sensitive to adrenal hormones (see ' Different from control at p i 0.001.…”

Section: Discussionsupporting

confidence: 59%

Glucocorticoid Regulation of Spermidine Acetylation in the Rat Brain

Ientile

Luca

Giorgio

et al. 1988

Journal of Neurochemistry

View full text Add to dashboard Cite

The effect of glucocorticoids on polyamine metabolism has been elucidated further by measuring putrescine, spermidine, and spermine levels as well as ornithine decarboxylase, S-adenosylmethionine decarboxylase, and N1-acetylspermidine transferase activities in the hippocampus, cerebellar cortex, vermis, and deep nuclei of adrenalectomized rats. At 6 h after corticosterone or dexamethasone administration, the specific activities of ornithine decarboxylase and N1-acetylspermidine transferase showed the greatest increases in all brain tissues examined, and at 12 h, S-adenosylmethionine decarboxylase activity was not increased significantly. The hippocampus and cerebellar regions displayed different responses to corticosterone and dexamethasone, corresponding to the distribution of glucocorticoid and mineralocorticoid receptors. Corticosterone and dexamethasone increased ornithine decarboxylase and N1-acetylspermidine transferase activities in a dose-dependent manner, with dexamethasone being more active than corticosterone in all tissues. However, estradiol, progesterone, testosterone, and aldosterone were only active at doses greater than 5 mg/kg. The great increases in ornithine decarboxylase and N1-acetylspermidine transferase activities were accompanied by a marked increase in putrescine level and a small decrease in spermidine level. Our data confirm that the hippocampus and cerebellum are glucocorticoid target tissues and suggest that the increase in the content of putrescine, following acute treatment with glucocorticoids, is dependent on ornithine decarboxylase as well as N1-acetylspermidine transferase induction.

show abstract

Section: Discussionsupporting

confidence: 59%

Glucocorticoid Regulation of Spermidine Acetylation in the Rat Brain

Ientile

Luca

Giorgio

et al. 1988

Journal of Neurochemistry

View full text Add to dashboard Cite

show abstract

“…This treatment schedule is a well-known model to induce an LH surge in the ovariectomized rat (Caligaris, Astrada & Taleisnik, 1971;Brown-Grant, 1974). Oestrogen treat¬ ment has furthermore been shown to increase pituitary polyamine levels in ovariectomized rats (Gray et al 1980). Though it would be premature to suggest a mechanism controlling polyamine biosynthesis in the pituitary gland during pro-oestrus it appears evident that oestrogen is involved.…”

Section: Discussionmentioning

confidence: 97%

“…Oestrogen treatment of ovariectomized rats has pre¬ viously been shown to result in an accumulation of polyamines in the rat pituitary gland (Gray, Jasper, Luttge et al 1980). The present study extends this observation into a more physiological context and explores the mechanism controlling the increase in pituitary content of polyamines.…”

Section: Introductionmentioning

confidence: 98%

Ornithine decarboxylase activity and polyamines in the anterior pituitary gland during the rat oestrous cycle

Persson¹,

Nilsson²,

Rosengren³

1985

Journal of Endocrinology

View full text Add to dashboard Cite

The biosynthesis of polyamines, an ubiquitous group of amines shown to be essential for normal cellular growth and differentiation, was studied in the rat anterior pituitary gland during the different stages of the oestrous cycle. The activity of ornithine decarboxylase (ODC), which catalyses the rate-limiting step in the biosynthesis of polyamines, was low during oestrus, metoestrus and dioestrus. However, a marked transitory rise in ODC activity was found in the pituitary gland on the evening of pro-oestrus. The rise in ODC activity was accompanied by an increase in the pituitary content of the polyamines putrescine and spermidine. Ovariectomy did not significantly change the basal ODC activity in the pituitary gland. Oestrogen treatment of ovariectomized rats resulted in a marked stimulation of pituitary polyamine biosynthesis. The largest effects were observed when oestrogen was given as two injections 72 h apart, which gave rise to levels of ODC activity comparable to those observed on the evening of pro-oestrus. The increase in polyamine synthesis in the anterior pituitary gland during pro-oestrus appeared not to be related to the preovulatory secretion of LH or prolactin, since neither LH-releasing hormone nor thyrotrophin-releasing hormone (which induces a secretion of prolactin) affected pituitary ODC activity. The observed biosynthesis of polyamines may be associated with the cellular proliferation which occurs in the anterior pituitary gland at oestrus.

show abstract

“…Oestrogen treat¬ ment has been shown to increase polyamine content of the hypothalamus and pituitary (Gray, Jasper, Luttge et al 1980) and uterus (Moulton & Leonard, 1969) of ovariectomized rats, and ODC activity in chicken oviduct (Cohen, O'Malley & Stastny, 1970). Similarly, testosterone brings about a gradual increase in ODC activity in the prostate of orchidectomized rats (Williams-Ashman, Pegg & Lockwood, 1969).…”

Section: Introductionmentioning

confidence: 95%

Differential effect of difluoromethylornithine on the increases in plasma concentrations of reproductive hormones on the afternoon of pro-oestrus in the rat

Nicholson

Wynne-Jones²

1989

Journal of Endocrinology

View full text Add to dashboard Cite

In our colony of female rats (220-320 g body weight) undergoing regular 4-day oestrous cycles there were significant, marked rises in concentrations of LH, FSH and prolactin between 09.00 and 19.00 h on pro-oestrus. The i.p. injection of difluoromethylornithine (DFMO; 40-400 mg/kg), a specific inhibitor of the activity of ornithine decarboxylase, at 15.00 h on pro-oestrus had a differential effect on the rise in plasma concentrations of the various hormones thereafter. The drug produced a significant, partial, dose-related suppression of the rise in plasma concentrations of LH and prolactin, but had no significant effect on the rise in FSH. For time-course studies, 120 mg DFMO/kg were injected at 13.00, 15.00 or 17.00 h and groups of animals killed at 19.00 h. Only the injection at 15.00 h was effective in causing a significant reduction in plasma concentrations of LH and prolactin at 19.00 h. Pituitary content of the hormones was found to be unaffected by the administration of DFMO at the times and doses tested. These results suggest that DFMO has a selective inhibitory effect on enhanced LH and prolactin secretion on the afternoon of pro-oestrus in the rat, whilst not affecting FSH release. There seems to be a limited time (after 13.00 but before 17.00 h) during which its administration is effective.

show abstract

Estrogen Increases Hypothalamic and Pituitary Polyamine Levels in Ovariectomized Rats

Cited by 9 publications

References 17 publications

Glucocorticoid Regulation of Spermidine Acetylation in the Rat Brain

Glucocorticoid Regulation of Spermidine Acetylation in the Rat Brain

Ornithine decarboxylase activity and polyamines in the anterior pituitary gland during the rat oestrous cycle

Differential effect of difluoromethylornithine on the increases in plasma concentrations of reproductive hormones on the afternoon of pro-oestrus in the rat

Contact Info

Product

Resources

About