EFFECT OF OVARIAN STEROIDS ON PREPUTIAL GLAND ODOURS IN THE FEMALE RAT

1978 ◽  
Vol 77 (3) ◽  
pp. 397-403 ◽  
Author(s):  
A. J. THODY ◽  
H. DIJKSTRA

Sexually experienced male rats were used to test for whole body and preputial gland odours of female rats. The male rats clearly preferred whole body odours of intact female rats to those of preputialectomized female rats. The male rats also preferred the odour of preputial gland tissue of intact female rats to that of ovariectomized female rats and were especially attracted to the preputial gland odours of female rats in pro-oestrus and oestrus. The preputial gland odours of ovariectomized rats that had received oestradiol benzoate for 7 days were attractive to male rats, although similar treatment with progesterone was ineffective. However, a single injection of progesterone given 72 h after a single injection of oestradiol benzoate not only made ovariectomized rats receptive, but also made their preputial gland odours attractive to male rats. The results suggest that the preputial gland of the female rat is responsible for odours that serve to attract sexually experienced male rats. Ovarian steroids, as well as controlling receptivity in the female rat, would also appear to control the production of sex attractants in the preputial gland. There was no relationship between the size of the preputial glands and their ability to attract male rats which suggests that preputial gland growth and production of sex attractants are not under the same hormonal control.

1981 ◽  
Vol 90 (1) ◽  
pp. 53-58 ◽  
Author(s):  
S. M. DONOHOE ◽  
A. J. THODY ◽  
S. SHUSTER

Sexually experienced male rats were used to test the attractiveness of preputial gland odours of female rats. The male rats showed a clear preference for the preputial gland odours of hypophysectomized females given oestradiol benzoate (OB) for 3 or 8 days to those of control rats. Progesterone treatment had no effect on the attractiveness of the preputial gland odours of OB-treated hypophysectomized female rats. Administration of α-MSH for either 3 or 8 days, on the other hand, increased the attractiveness to male rats of preputial gland odours of OB-treated hypophysectomized females and the presence of progesterone produced no further change. When administered alone α-MSH had no effect on the attractiveness of the preputial gland odours. Other pituitary hormones, such as ACTH and prolactin, had no effect on the attractiveness of preputial gland odours of OB-treated hypophysectomized rats when administered for 3[unk]days. An increase in preputial gland size was only seen when OB, progesterone and α-MSH were administered together. It would appear that no relationship exists between the size of the preputial glands and their ability to attract male rats. It is concluded that, while α-MSH and progesterone may be important in controlling growth of the preputial glands, an interaction between α-MSH and oestrogen is more important for regulating the production of sex attractants by the preputial glands.


1986 ◽  
Vol 109 (1) ◽  
pp. 1-7 ◽  
Author(s):  
A. M. Alves ◽  
A. J. Thody ◽  
C. Fisher ◽  
S. Shuster

ABSTRACT Lipogenesis was measured in isolated preputial gland cells of female rats after ovariectomy and after the administration of oestradiol benzoate. Ovariectomy decreased preputial gland cell lipogenesis and also altered the pattern of lipid synthesis, producing a relative decrease in the proportion of polar lipids and an increase in the proportion of 'triglycerides'. Although daily administration of 2 or 10 μg oestradiol benzoate for 7 days produced slight increases in preputial gland cell lipogenesis in ovariectomized rats, the effects were not significant. A single injection of 10 μg oestradiol benzoate, however, produced significant increases in preputial gland cell lipogenesis of ovariectomized rats at both 2 and 24 h and, moreover, at 24 h the pattern of polar lipid and triglyceride labelling was restored to normal. Prior administration of actinomycin D reduced the lipogenic effect of oestradiol benzoate. Oestradiol benzoate had little or no effect on preputial gland cell lipogenesis in male rats. These results confirm that oestrogen is able to stimulate preputial lipogenesis in female rats. Whether this action of oestrogen is related to its pheromone-producing effect on the preputial glands is not yet known. J. Endocr. (1986) 109, 1–7


1980 ◽  
Vol 86 (1) ◽  
pp. 189-191 ◽  
Author(s):  
S. C. BELL

The effects of ovarian hormones on the synthesis of α2-macroglobulin in response to injury were investigated. After injection of turpentine to provoke synthesis of α2-macroglobulin, the mean concentrations of this protein in serum were lower in intact female than in male rats. Sera from injured ovariectomized rats contained levels of α2-macroglobulin similar to those of injured male animals. Administration to ovariectomized animals of oestradiol or oestradiol plus progesterone substantially reduced the levels of α2-macroglobulin produced in response to injury. Administration of progesterone only resulted in a small increase in the response of ovariectomized animals to injury. Oestradiol and progesterone had no effect on the response of male rats to injury. These findings suggest that only in the female rat can these steroid hormones, especially oestradiol, regulate the synthesis of α2-macroglobulin in response to tissue injury.


1975 ◽  
Vol 64 (1) ◽  
pp. 27-35 ◽  
Author(s):  
F. R. BURNET ◽  
P. C. B. MACKINNON

SUMMARY The rate of [35S]methionine incorporation into protein in discrete cerebral areas was measured before and after the administration of oestradiol benzoate (OB) to chronically ovariectomized rats. The circadian rhythm of incorporation which is normally seen in the intact cyclic female rat was deleted by ovariectomy. A daily rhythm of incorporation reappeared, however, in all the brain areas studied 30 h after a single injection of OB (20 μg), and was still present 12 days later. The release of luteinizing hormone (LH) after administration of 20 μg OB was measured in chronically ovariectomized animals and was found to be biphasic. High levels of LH after ovariectomy were initially reduced by negative feedback, but this phase was followed 52 h later by a facilitation of LH release between 15.00 and 18.00 h. The facilitation of LH release at this time of day was still detectable 12 days after the initial injection. The evidence for a functional link between the rhythm of neural activity which is reflected by [35S]methionine incorporation, and the ability to 'time' the facilitation of LH release is discussed.


1977 ◽  
Vol 74 (2) ◽  
pp. 315-NP ◽  
Author(s):  
A. DANGUY ◽  
J. L. PASTEELS ◽  
F. ECTORS

A single injection of 1 mg of a complex of testosterone esters on day 5 of life was used to prepare constantly oestrous rats. Such androgenized female rats were then ovariectomized and submitted to stereotaxical implantation of 1 μg oestradiol benzoate, 5 μg testosterone isobutyrate or, as a control, 10 μg cholesterol in the anterior hypothalamic areas. The effects of the steroids on plasma and pituitary FSH and LH were assessed by radioimmunoassay. As reported previously by us in normal female and male rats, the preoptic–suprachiasmatic area (POA) was able to control synthesis and secretion of both gonadotrophins and did not lose its sensitivity to oestradiol and testosterone in androgenized rats. Evidence for enhanced prolactin secretion in androgenized rats was derived from immunofluorescence studies of the pituitary gland and from histology of the mammary glands. In this respect the condition of the androgenized females was opposite to that of the males. The present work demonstrated that stimulation of prolactin secretion in androgenized female rats resulted from oestrogen action due to permanent oestrus rather than from impairment of hypothalamo-hypophysial relationships. Indeed, prolactin stimulation was suppressed when the androgenized rats were ovariectomized and restored when they were subsequently implanted with oestradiol in the POA.


1987 ◽  
Vol 113 (3) ◽  
pp. 429-434 ◽  
Author(s):  
G. Forsberg ◽  
I. Bednar ◽  
P. Eneroth ◽  
P. Södersten

ABSTRACT Sexual receptivity was inhibited in ovariectomized rats treated with oestradiol benzoate (OB: two injections of 2 μg) and progesterone (0·5 mg) immediately after ejaculation by the male and restored after the end of the post-ejaculatory refractory period in the male. The post-ejaculatory inhibition of sexual receptivity was reversed by i.p. (5 mg), intracerebroventricular (50 μg) or intrathecal (50 μg) injection of the opioid peptide receptor antagonist naloxone. The concentration of serum β-endorphin-like immunoreactivity in ovariectomized rats treated with OB plus progesterone was unaltered by sexual interactions with males (18·3 ± 6·0 (s.e.m.), 26·4 ± 2·1 and 21·8 ± 6·1 pmol/l before sexual activity, after ejaculation and after the end of the post-ejaculatory interval) but reduced to non-detectable by hypophysectomy. Subcutaneous injection of 10 μg β-endorphin raised serum concentrations of β-endorphin-like immunoreactivity but did not affect the display of sexual behaviour. The behaviour was also unaffected by intracerebroventricular injection of 0·1, 0·2 or 1·0 μg β-endorphin or by injections of 0·25 μg β-endorphin in the periaqueductal central grey of the mesencephalon. The results show that ejaculation by male rats causes a transient inhibition of sexual receptivity in the female which may be dependent upon opioid peptide receptor mechanisms in the brain and spinal cord. It is unlikely that the peptide is β-endorphin. J. Endocr. (1987) 113, 429–434


1979 ◽  
Vol 83 (2) ◽  
pp. 267-274 ◽  
Author(s):  
S. HANSEN ◽  
P. SÖDERSTEN ◽  
P. ENEROTH ◽  
B. SREBRO ◽  
K. HOLE

Ovariectomized rats exposed to constant plasma levels of oestradiol showed a daily rhythm in lordosis behaviour, with high levels of lordosis occurring during the dark portion of the daily light: darkness cycle and low levels during the light period. Similarly treated male rats failed to show a rhythm in lordosis behaviour. However, neonatal castration permitted the expression of the lordosis rhythm in male rats; conversely, an injection of 1·25 mg testosterone propionate on day 4 of life abolished the rhythm in female rats. Pinealectomy, adrenalectomy or depletion of brain 5-hydroxytryptamine levels did not affect the periodicity in lordosis behaviour but lesions in the suprachiasmatic nuclei of the hypothalamus disrupted the rhythm. It is suggested that the daily rhythm in lordosis behaviour participates in the control of the termination of heat in the female rat and that the perinatal hormone milieu may exert permanent effects on periodic functions.


1978 ◽  
Vol 78 (1) ◽  
pp. 31-38 ◽  
Author(s):  
G. VANDOREN ◽  
H. VAN BAELEN ◽  
G. VERHOEVEN ◽  
P. DE MOOR

Evidence is presented that the level of α2u-globulin in the serum of male rats depends, at least in part, on neonatal androgens. After castration of adult animals the concentration of this protein falls but remains measurable, whereas in intact or ovariectomized female rats α2u-globulin cannot be detected. Moreover, α2u-globulin is found in adult male and female rats gonadectomized at birth and treated with a single injection of testosterone propionate immediately thereafter. The mechanism by which neonatal androgens increase the concentration of α2u-globulin has been investigated. Transplantation of a supplementary pituitary gland under the renal capsule of male rats resulted in reduced levels of α2u-globulin and increased levels of transcortin. The changes discussed here were observed only in those animals in which the transplant was functional and they were amplified or reversed by modulators of prolactin secretion such as oestrogens or bromocriptine respectively. The hypothesis is advanced that neonatal androgens stimulate the production of a hypothalamic inhibitory factor that controls the secretion of prolactin, or another hypophysial hormone subjected to similar neuroendocrine control. Measurements in gonadectomized animals and in rats receiving both oestradiol benzoate and bromocriptine indicate that, besides these pituitary-mediated effects, both oestrogens and androgens exert direct effects on the level of α2u-globulin.


2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 120-120
Author(s):  
Yaqi Li ◽  
Ayasa Tajima ◽  
Floyd Mattie ◽  
Erin Dexheimer ◽  
Elizabeth Soucy ◽  
...  

Abstract Objectives We investigated the impact of pregnancy and lactation on vitamin A (VA) metabolism and kinetics in rats, hypothesizing that this changed physiological status would perturb whole-body VA kinetics. Such information may be informative for future dietary recommendations. Methods Ten female rats (7 wk of age) and 6 male rats (9 wk of age) were fed an AIN-93 G diet upon arrival. After 1 week of acclimation, female rats received an oral dose of 3H-labeled retinol as the tracer to initiate the kinetic study. On d 21 after dosing (when 3H-retinol was expected to reach a log-linear terminal slope), 6 female rats were mated and checked daily for a vaginal plug to determine the date of pregnancy. On the day of delivery, litter size was adjusted to 10 pups/dam. Serial blood samples were collected from each female rat at 27–28 time points after dose administration until dams and pups were euthanized on d 14 of lactation. Hematocrit was measured, plasma tracer level was determined, and plasma fraction of dose vs. time was plotted. Model-based compartmental analysis will be applied to the plasma tracer data to develop VA kinetic models. Results All mated female rats became pregnant (pregnant group, PG, n = 6). Non-mated female rats were studied as non-pregnant controls (CN, n = 4). No difference was observed in hematocrit between PG and CN rats, suggesting no significant change in plasma volume expansion. Before breeding, plasma tracer response profiles were similar to CN rats. However, a consistent decline in plasma tracer levels was observed in PG rats during the middle of pregnancy, followed by a rise in late pregnancy, whereas such a change did not occur in CN rats. Moreover, during lactation, PG rats exhibited a steeper terminal slope compared to CN rats, indicating a more rapid utilization of VA in these lactating rats. Conclusions Pregnancy and lactation resulted in altered VA metabolism and kinetics in rats. Further analysis using mathematical modeling will explore the changes in kinetic parameters that underlie the perturbations we have observed in VA kinetics. Funding Sources National Institutes of Health.


1965 ◽  
Vol 49 (2) ◽  
pp. 231-238 ◽  
Author(s):  
T. Swelheim

ABSTRACT A single injection of 50 μg oestradiol benzoate, administered at 11 a.m. to adult female rats which had been spayed 14 days previously and had since been treated with 0.5 μg oestradiol benzoate daily, led to an increase in the ICSH-content of the serum, which was determined 29 hours after the injection. In an identical experimental design a decrease in the ICSH-content of the serum was found in adult male rats. ICSH-determinations were carried out by the ventral prostate assay. A stimulating effect upon the ventral prostate of oestrogen present in the serum used for the above determinations was excluded. At the time when the changes in the serum were established, there were no demonstrable changes in the ICSH-content of the anterior pituitary gland in both sexes. The existence of a fundamental sex difference in the response to a single high dose of oestrogen is suggested.


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