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1.
The present study investigated the immunolocalization of the progesterone and oestrogen α receptors in the uterine horns of the African giant rat during the oestrous cycle. The progesterone and oestrogen α receptors were demonstrated in various cellular constituents of the endometrium, myometrium and perimetrium. The intensity of progesterone and oestrogen α receptor immunostaining in the endometrial and myometrial layers of the uterine horns varied during the oestrous cycle. The intensity of oestrogen α receptor immunoreactivity in the luminal epithelium was high during pro‐oestrus, oestrus and dioestrus. Progesterone and oestrogen α receptor immunoreactivity in the endometrial epithelia was absent during metoestrus. Moderate to strong immunostaining for the progesterone and oestrogen α receptors was demonstrated in the myometrial smooth muscle cells during pro‐oestrus, oestrus and dioestrus. The intensity of progesterone and oestrogen α receptor immunostaining in the myometrial smooth muscle cells was low during metoestrus. Stromal cells in the perimetrium consistently expressed progesterone and oestrogen α receptor immunoreactivity throughout the oestrous cycle. The findings of the study indicate that in the giant rat the immunolocalization of the progesterone and oestrogen α receptors, in endometrial and myometrial regions of the uterine horns, varies during the oestrous cycle.  相似文献   

2.
The concentrations of receptors for epidermal growth factor (EGF-R), oestrogen (ER) and progesterone (PR) were measured in 108 samples from canine mammary tumours and 132 samples of normal mammary tissue removed surgically from 84 bitches. The history and clinical signs were also recorded. Binding sites of high affinity were detected in 70 per cent of both types of tissue and no significant variations in EGF-R concentrations or positivity were observed with the histology, location, size or number of mammary tumours or the age of the animal. A significant direct correlation (P=0002) was observed between the concentrations of ER and EGF-R only in malignant tumours. The concentrations of EGF-R were significantly correlated (P=0.04) in normal mammary tissues adjacent to and distant from the lesions, but not between normal tissue and tumour tissue. No significant differences were observed in the expression of EGF-R in normal and neoplastic tissues from the same bitches. The direct correlation between the concentrations of EGF-R and ER in malignant tumours could be related to an oestrogen-dependent expression of EGF-R or to a similar pattern of regulation of the receptors.  相似文献   

3.
Changes in the concentrations and affinities of receptors for oestrogen (ER), progesterone (PR) and epidermal growth factor (EGF-R) were studied in mammary glands of healthy bitches with regard to age, the location in the mammary chain and the stage of the oestrous cycle. Uterus was used as the reference tissue for the evaluation of steroid receptors. Mammary and uterine samples from 7 healthy bitches were taken at five stages of the oestrous cycle in such a way that all the locations in the mammary chain were represented at each stage of the cycle (10 samples/dog). ER, PR and EGF-R were detected by biochemical assays using increasing concentrations of tritiated (steroids) or iodinated (EGF) ligands. A significant direct correlation was found between the ER and PR concentrations for mammary and uterine samples. No significant correlation was found between the steroid receptors and EGF-R concentrations. Mammary ER concentrations were significantly higher in bitches of 5 years of age or older than in younger ones; in posterior glands (4th and 5th pairs) than in anterior glands; and in the mid-luteal phase. Mammary PR did not vary significantly with age or location but was significantly lower in the early luteal phase than in other phases. A similar decrease in PR concentrations was observed in the uterus during the early luteal phase and uterine ER and PR concentrations were very low in the mid-luteal phase. Mammary EGF-R were not significantly higher in the early or mid-luteal phase than in pro-oestrus or anoestrus.The differences observed between the uterine and mammary steroid receptor concentrations during the oestrous cycle could be due to different mechanisms for regulating steroid receptor expression in the two tissues. Mammary EGF-R concentrations may be linked, as in other species, to cellular proliferation and/or to the serum progesterone concentrations.Abbreviations BSA bovine serum albumin - EGF epidermal growth factor - EGF-R receptor for epidermal growth factor - ER oestrogen receptor - K d dissociation constant - LH luteinizing hormone - p probability of error - PR progesterone receptor  相似文献   

4.
Two juvenile (9 months) and two adult (3 years) beagle bitches were injected with five doses (250 i.u. per dose) of pregnant mare serum gonadotrophin (PMSG) on alternate days. Plasma oestrogen concentrations rose in all bitches. In one adult bitch plasma progesterone concentrations remained basal and no signs of oestrus were shown; in the other there was a slight elevation of circulating progesterone values and she showed oestrus but did not conceive. Both the young bitches came into heat and had multiple ovulations, producing very high plasma progesterone concentrations. One of them conceived, and at laparotomy on the thirty-sixth day after the first mating seventeen conceptuses were seen; 14 days later ovarohysterectomy was performed and only five foetuses remained in the uterus.  相似文献   

5.
The aim of this study was to determine the effects of gonadotrophin releasing hormone (GnRH) administration on the plasma concentrations of reproductive hormones in intact and ovariectomized (OVX) bitches. Therefore, blood samples were collected at multiple times before and after the administration of 10 microg/kg GnRH (Fertagyl)) for the determination of the plasma concentrations of luteinizing hormone (LH), oestradiol, progesterone and testosterone in six anoestrus and in six OVX bitches. The mean plasma LH concentrations before and 60 min after GnRH administration were significantly lower in the anoestrous bitches than in the OVX bitches. In both groups GnRH administration resulted in a significant increase in the plasma LH concentration. The highest plasma LH concentrations were found at 10 min after GnRH administration and these values did not differ significantly between the two groups. Only in the anoestrous bitches a significant increase in plasma oestradiol concentrations was found after GnRH administration and these values were significantly higher than those in the OVX bitches. The plasma concentrations of progesterone and testosterone were low (close to or below the limit of quantitation) both before and after GnRH administration and the differences between anoestrous and OVX bitches were not significant. It can be concluded that (i) basal plasma LH concentration is significantly higher in OVX bitches than in anoestrous bitches, (ii) plasma LH concentration increases after GnRH administration in both anoestrous and OVX bitches, (iii) GnRH administration causes a significant rise in plasma oestradiol concentration only if ovarian tissue is present and (iv) measurement of plasma progesterone and testosterone concentrations before and after GnRH administration does not aid in distinguishing between anoestrous and OVX bitches. The results of this study may provide a basis for the diagnosis of remnant ovarian tissue and verification of neuter status in the bitch.  相似文献   

6.
The aetiology and pathogenesis of spontaneous cystic endometrial hyperplasia (CEH) in the bitch is not yet completely understood. Recent research based on the expression of uterine sex hormone receptors in spontaneous cases of CEH suggested that a temporary progesterone deficiency during late oestrus-early metoestrus may be responsible for the onset of CEH development. In the present study a temporary progesterone deficiency during late oestrus–early metoestrus was experimentally created using an inhibitor of progesterone synthesis, epostane. At day 49 of metoestrus, there was a significant reduction in the size of the uterine wall, mainly due to endometrial atrophy, and there was also a significant increase in the mucus-filled uterine lumen in the bitches that had been treated with epostane compared to the control bitches. No significant differences in the expression of sex hormone receptors was observed between the two groups. As no CEH developed in the epostane-treated bitches, an additional oestrogenic stimulus may be required to stimulate endometrial proliferation. Therefore, it is suggested that deficient luteinization of the corpus luteum may be the trigger in the pathogenesis of CEH, as the secretion of varying amounts of sex steroids depends on the degree of luteinization.  相似文献   

7.
Reasons for performing study: Fillies completely devoid of endometrial glands (uterine gland knockout; UGKO) would make ideal experimental models in which to study the role of endometrial histotroph in embryogenesis and early fetal development in the mare. Hypothesis: Administration of a synthetic progestagen plus oestrogen to newborn filly foals and, thereafter, at regular intervals to age 6 months, would permanently suppress endometrial gland development. Methods: Nine half‐sister Thoroughbred filly foals were treated, in 3 groups, with: A) the weakly active progestagen, norgestomet, administered from birth to age 6 months, in subcutaneous implant form plus oestradiol valerate and norgestomet i.m. at fortnightly intervals; B) the strongly active oral progestagen, altrenogest, administered daily from birth to age 6 months plus fortnightly injections of oestradiol valerate and norgestomet; C) nothing (untreated controls). Endometrial biopsies were recovered from all fillies at ages 6 months and 2 years to assess the degree of endometrial gland morphogenesis and to determine immunohistochemically the presence or absence of oestrogen and progesterone receptors in the endometrial tissues. Results: Groups B and C showed no endometrial gland development, whereas Group A fillies showed a high degree of endometrial gland development, plus strong staining for both oestrogen and progesterone receptors at age 6 months. All 9 fillies showed full normal endometrial gland morphogenesis, development and function at age 2 years. Conclusions and relevance: While the administration of a strongly active progestagen over‐rode the actions of the concomitantly administered oestrogen and suppressed endometrial gland development during the period of administration, treatment with oestradiol valerate together with a weakly active progestagen, stimulated precocious endometrial gland development. Neither steroid was able to create the desired UGKO experimental model and all fillies showed normal endometrial gland development and fertility after puberty. Hence, ovarian oestrogen, not progesterone, appears to be the basic stimulus for endometrial gland morphogenesis in the horse.  相似文献   

8.
The deep anoestrous phase in winter is part of the anovulatory season in mares and is bordered by the autumn and spring transitional periods (ATP/STP). To define an annual time span for effective prognostic biopsy sampling, the aim of this study was to provide a morphofunctional characterization of the endometrium during ATP and STP. To outline both transitional periods, endometrial specimens were taken in September, October and November (n = 76) as well as February, March and April (n = 184) with the requirement of a detailed clinical documentation. Tissue samples were examined histologically with special emphasis on the functional endometrial morphology. Additionally, an immunohistochemical evaluation was performed on selected specimens regarding the expression of oestrogen receptor α, progesterone receptor and Ki67‐antigen. An absent to low endometrial activity was ascertained in more than 60% of all specimens from late October onwards, whereas a comparably lacking or low activity in STP was observed until early April. Approximately 30% (ATP) to 22% (STP) of all samples exhibited a predominantly “irregular” endometrial differentiation. During the transitional periods, the clinically evaluated ovarian status (transrectal palpation, transrectal ultrasonography and/or serum progesterone and oestrogen analyses) and the endometrial functional morphology were in accordance with approximately 70% of all cases. The expression of steroid hormone receptors and Ki67‐antigen was generally low. Given that endometrial maldifferentiations were frequently found during ATP and STP, its occurence might display a characteristic and physiological feature of the transitional periods. Regarding the functional endometrial morphology, a diagnostic biopsy sampling should therefore be performed between late April and before September.  相似文献   

9.
The changes in total unconjugated oestrogen and progesterone concentrations in the peripheral blood of one bitch throughout a false pregnancy were measured. The levels of these hormones detected in 11 bitches when examined during a false pregnancy, and in 13 other bitches with pyometa are also reported. Oestrogen and progesterone concentrations were within normal limits in both of these conditions where single samples were obtained, but the bitch with false pregnancy studied in detail showed a raised oestrogen level during metoestrus. The significance of these results is discussed in relation to previous studies on the aetiology of false pregnancy and pyometra.  相似文献   

10.
Cystic endometrial hyperplasia-pyometra complex is the most frequent and important endometrial disorder encountered in bitches. The pathogenesis of the disease is related to the activity of progesterone [Feldman and Nelson, Canine and Feline Endocrinology and Reproduction (1996) W.B. Saunders, Philadelphia]. Cystic endometrial hyperplasia (CEH) is an abnormal response of the bitch's uterus to ovarian hormones [De Bosschere et al. Theriogenology (2001) 55, 1509]. CEH is considered by many authors to be an exaggerated response of the uterus to chronic progestational stimulation during the luteal phase of the oestrous cycle, causing an abnormal accumulation of fluid within the endometrial glands and uterine lumen (De Bosschere et al. 2001). The resulting lesions of pyometra are due to the interaction between bacteria and hormones. The aim of this study was to evaluate if transabdominal uterine ultrasonography can be a useful and reliable diagnostic method to confirm Dow's [Veterinary Record (1958) 70, 1102] and De Bosschere's histopathological classification of CEH-pyometra complex. The study was carried out on 45 bitches with pyometra, 10 purebreds and 35 crossbreeds, 1-15 years old, 20% of which had whelped at least once. None of these animals had received exogenous oestrogen or progesterone treatment. On admission the 45 animals were in the luteal phase of the oestrus cycle. Clinical signs, blood parameters, uterine ultrasonography, bacterial swabs and uterine histopathological results were recorded. Results suggest that ultrasonographic examination is a useful and reliable tool for the diagnosis of cystic endometrial hyperplasia.  相似文献   

11.
A 125I radioimmunoassay (RIA) has long been used to determine the value of progesterone in serum or plasma of bitches but was discontinued in 2014. A chemiluminescence immunoassay (CLIA) gained prominence since 2003 to determine the value of progesterone in serum of bitches but the assay changed in 2012. This study assessed the agreement between progesterone values obtained with RIA in plasma (progRIA) and with the post‐2012 CLIA (progCLIA) in the serum of bitches. ProgCLIA was determined in 110 serum samples from 40 bitches in pro‐oestrus or early oestrus and compared to progRIA in plasma samples collected from the same bitches at the same time, where progRIA had a uniform distribution between 0.5 and 25 nmol/L. Two replicate analyses of each serum or plasma sample were simultaneously done in the same assay. For RIA and CLIA, the intra‐assay CVs were 5.85% and 6.70% and the interassay CVs 8.45% and 9.16%. For RIA and CLIA the progesterone values obtained with replicate analyses differed by as much as 11%–31% in 25% of samples. On average, the value of progCLIA was 85% of that of progRIA (95% CI 58%–112%, n = 110), with 88% of progCLIAs being lower than the progRIAs. This study shows that RIA and CLIA may yield replicate values that differ by as much as 11%–30% in about a quarter of samples analysed, necessitating replicate analyses if precise values are required. The study provides an equation by which to estimate progCLIA from progRIA.  相似文献   

12.
The distribution of oestrogen and progesterone receptors in the equine genital tract was investigated by means of a modified dextran-coated charcoal method on samples collected from the vagina, the cervix and the uterus of 30 healthy adult Polish mares, divided into two groups on the basis of their serum progesterone levels. The concentrations of oestrogen and progesterone receptors were significantly (P<0·05) lower in the vagina and the cervix than in the uterus, in agreement with data from human beings, cattle and pigs, which showed that the highest concentrations of oestrogen and progesterone receptors were localised respectively in the body and in the horns of the uterus.  相似文献   

13.
The expression of hormone receptors and their relationship to cell proliferation in six samples of normal canine mammary tissue, and 11 benign and 10 malignant mammary neoplasms from female dogs were assessed by immunohistochemistry in formalin-fixed paraffin-embedded samples, by using monoclonal antibodies against progesterone and oestrogen receptors, and nuclear antigen Ki-67 (MIB-1). Malignant tumours negative for progesterone receptors proliferated at higher rates than progesterone receptor-positive tumours, suggesting that the progression towards malignancy in spontaneous mammary tumours is accompanied by a decrease in hormonal steroid dependency. Only one malignant tumour was positive for oestrogen receptors.  相似文献   

14.
Influence of progesterone and pregnancy on canine fibrinogen values   总被引：2，自引：0，他引：2  
Progesterone alone or in combination with oestrogen was given to male dogs and nonoestrous bitches by intramuscular injection. Progesterone produced a marked increase in plasma fibrinogen values. The fibrinogen response appeared to be independent of oestrogen administration. No alteration in haematocrit values, platelet count, APTT and OSPT results or the activities of coagulation factors VII, VIII and IX was observed following hormone administration. It is suggested that increased plasma progesterone concentrations may be partly responsible for the two- to three-fold increase in fibrinogen which occurs during gestation in the bitch.  相似文献   

15.
In two cases of granulosa cell tumours of the ovary in bitches there was production of sex hormones by the neoplasm. Both tumours produced oestrogens but one also produced significant concentrations of progesterone. In both bitches, the presenting sign was abnormally prolonged oestrus activity. One dog also developed a haemorrhagic diathesis as a result of endogenous oestrogen toxicity.  相似文献   

16.
The role of prolactin on luteal function in dogs was investigated in vivo. The function of prolactin in mid-luteal phase was compared in pregnant and nonpregnant dogs. A dopamine agonist, cabergoline, known for its prolactin secretion inhibitory effects, was injected subcutaneously at a dose of 5 μg/kg body weight in five pregnant and five nonpregnant Beagle bitches. Mean plasma prolactin and progesterone were dramatically suppressed for 4 to 5 days after injection in both groups when compared with control pregnant and non-pregnant animals, whereas no effect on luteinizing hormone (LH) secretion was observed. The decline in plasma progesterone occurred after that in prolactin, suggesting plasma progesterone was impaired by inhibition of prolactin secretion. These results confirm the luteotropic importance of prolactin in pregnant bitches, and also demonstrate its importance in luteal phase of the nonpregnant dog.Second, to demonstrate that the effects of cabergoline were mediated by prolactin inhibition and not by a direct action on the corpus luteum, concomitant administration on Day 30 of cabergoline and prolactin (375 μg IV twice daily on Days 30 and 31) or cabergoline and LH (750 μg IV twice daily on Days 30 and 31) was affected in two groups of five pregnant animals each. Results showed that only prolactin was able to reverse the negative effects of cabergoline on circulating progesterone. This confirms the indirect mode of action of the dopamine agonist, cabergoline on corpus luteum function.Third, further investigation on the precise luteotropic role of prolactin was made by IV injection of 375 μg pure canine prolactin twice daily in five pregnant bitches on Days 30 and 31, and in five pregnant bitches on Days 40 and 41. No direct stimulatory effect of prolactin on plasma progesterone secretion occurred. Nor was there a noticeable effect on plasma LH secretion. These results suggest that prolactin is unable to directly stimulate progesterone secretion by the corpus luteum of pregnancy.The results of this study suggest that prolactin is an essential luteotropin in the dog from mid-luteal phase in both pregnant and nonpregnant animals. However, it appears to act by sustaining corpus luteum lifespan and function rather than by direct stimulatory effects on progesterone secretion.  相似文献   

17.
Aglepristone, a competitive progesterone antagonist, is successfully used in various progesterone-dependent conditions. This study investigated uterine histomorphometric analysis, and expressions of the oestrogen α receptor (ERα) and progesterone receptor (PR) in uteri of bitches following the single dose of aglepristone treatment. Twelve client-owned healthy diestrous bitches were used in the study. The single dose of aglepristone (Alizine®, 10 mg/kg) was injected subcutaneously 5 days before ovariohysterectomy in the treatment group (n = 6); bitches without treatment served as a control group (n = 6). Uteri were collected for histomorphometric analysis, ERα and PR gene, and protein expressions studies. The mRNA expressions of ERα and PR were determined by RT-qPCR. Immunohistochemical analysis was used to evaluate the ERα and PR protein expressions using an H-score in five parts of the uterus. The results demonstrated glandular epithelium height significantly decreased (p < .05) and ERα mRNA increased (p < .01) in treated dogs. Of the treated bitches, lower expression levels of ERα were observed in the luminal epithelium, crypt and glandular epithelium, with higher expression in the endometrial stroma and myometrium (p < .05); however, PR expression decreased in the luminal epithelium, crypt and glandular epithelium (p < .01). In conclusion, reduction of the uterine glandular epithelium and ERα mRNA upregulation together with changes in ERα and PR expressions were observed in the treated bitches. However, changes in uterine ERα and PR expressions in the treated bitches depended on tissue layers. The treatment had no effect on serum oestradiol and progesterone levels.  相似文献   

18.
The aim of the study was to localize oxytocin receptors (OTR) and measure mRNA expression of OTR in the canine uterus with and without the influence of progesterone. Uterine samples were taken from nine anoestrous and eight dioestrous bitches during ovariohysterectomy. Histological changes were evaluated in haematoxylin and eosin (HE)‐stained samples. Purified polyclonal antibody for OTR was used in immunohistochemistry to localize receptors in uterine layers. Relative mRNA concentration of OTR was evaluated with real‐time PCR from full‐thickness uterine samples taken from the middle horn and the body. Myometrial smooth muscle cells, endometrial luminal epithelium (LE) and deep and superficial glandular epithelium were positively stained for oxytocin receptors in non‐pregnant animals. No significant difference in staining intensity was detected between uterine middle horn and body. However, the staining intensity of LE was significantly higher in dioestrous than in anoestrous uteri (p < .05). Leucocytes and endothelium of blood vessels were also positively stained for OTR. Real‐time PCR showed no significant differences in OTR mRNA expression between the middle horn and the body of the uterus, or between anoestrous and dioestrous uterus. No correlation was noted between OTR mRNA expression and blood progesterone concentration. In conclusion, despite the apparent inactivity, the uterus of the non‐pregnant bitch expresses OTR. The distribution or relative expression of OTR does not differ between uterine horn and body in dioestrus or anoestrus except in LE. LE may have more oxytocin‐dependent activity during dioestrus than anoestrus.  相似文献   

19.
Cystic endometrial hyperplasia (CEH) was experimentally reproduced by the intraluminal insertion of a silk wire in the uterus of metestral bitches to obtain a model for the study of spontaneously occurring CEH in the bitch. This mechanically reproduced CEH corresponded histologically very well to spontaneously occurring CEH. With respect to sex hormone receptor expressions, however, there was no similarity. In the mechanically induced CEH, progesterone receptor expression was reduced in the epithelial cells (surface epithelium and endometrial glands) and slightly increased in the stromal fibroblasts and myometrium as compared with the normal metestrus uterus. The oestrogen receptor expression in mechanically induced CEH was reduced in the epithelial cells (surface epithelium and endometrial glands) and more or less unchanged in the stromal fibroblast and myometrium as compared with the normal metestrus uterus. This is in contrast to the increased sex hormone receptor expressions in all uterine cell types, observed in spontaneously occurring CEH. The mechanically induced CEH model corresponds immunohistochemically more to early placentation and to pyometra in the bitch. Thus this experimental CEH model is not suitable for pathogenic studies of spontaneously occurring CEH in the bitch.  相似文献   

20.
Receptors for estrogen and progesterone were measured in cytosols prepared from specimens of canine endometrium obtained at late proestrus, day 4 of estrus, day 2 of diestrus, and at 10 day intervals from days 10 through 80 of diestrus. Twenty nine adult bitches were used, with 2 to 4 dogs used at each time point. Concentrations of estradiol receptors measured in endometrial cytosols from late proestrus through day 10 of diestrus were similar (mean +/- SEM: 9.9 +/- 2.2, 10.5 +/- 1.2, 16.3 +/- 1.6, and 16.2 +/- 2.9 pmol/g of tissue at proestrus, day 4 of estrus, days 2 and 10 of diestrus, respectively). As serum concentrations of progesterone increased during early diestrus, the concentration of estradiol receptors decreased and were significantly (P less than 0.05) lower on days 30 (4.9 +/- 1.3 pmol/g of tissue) and 40 (3.7 +/- 0.6 pmol/g of tissue) of diestrus. After day 40 of diestrus, when serum concentrations of progesterone were approaching basal concentrations, the concentration of estradiol receptors increased and remained significantly (P less than 0.05) higher from days 60 to 80 of diestrus (day 60, 13.4 +/- 2.9; day 70, 15.7 +/- 1.7; day 80, 19.8 +/- 2.4 pmol/g of tissue). As observed for estrogen receptors, the concentration of endometrial receptors for progesterone also gradually increased from late proestrus (4.9 +/- 1.3 pmol/g of tissue) to day 2 of diestrus (6.4 +/- 0.3 pmol/g of tissue).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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