Vaginal microflora in a rat model of polycystic ovarian disease

1983 ◽  
Vol 41 ◽  
pp. 560-561
Author(s):  
K.B. Singh ◽  
Ram P. Tewari ◽  
F. K. Khosho
Keyword(s):  
Reproductive Tract ◽  
Continuous Light ◽  
Hormonal Control ◽  
Female Rats ◽  
Surface Epithelium ◽  
Polycystic Ovaries ◽  
Vaginal Microflora ◽  
Sterile Normal Saline ◽  
Persistent Estrus

Exposure of female rats to continuous light for prolonged periods induces persistent estrus (PE), an anovulatory disorder. Instead of cyclic fluctuations, the vaginal smears from PE rats show only cornified cells as the hormonal control of the estrous cycle becomes inappropriate, and ovaries become cystic when ovulation ceases. The reproductive tract, a key target organ in PE, shows numerous manifestations of chronic estrogenic influence.In this paper, we report our findings on bacterial colonizations and ultrastructural examinations of the vaginal surface epithelium of PE rats with polycystic ovaries (PCO). Quantitation of bacteria in the vaginal lavage was done with a standard volume of sterile normal saline and studied in five different hormonal states: diestrus day 1 (D-1), diestrus day 2 (D2), proestrus (Pro E), estrus (E), and persistent estrus (PE). Scanning electron microscopy (SEM) was used to examine the vaginal surface epithelium from PE rats with PCO and compared to the controls. In all rats, cardiovascular perfusion was performed for in vivo fixation of the organs using 2.5% glutaraldehyde in 0.1 M Na Cacodylate buffer (pH 7.3) for 30 minutes.

Ultrastructure of the Surface Epithelium of the Polycystic Ovary in Constant Light Rats

1982 ◽  
Vol 40 ◽  
pp. 240-241
Author(s):  
K. B. Singh ◽  
F. K. Khosho
Keyword(s):  
Electron Microscopy ◽  
Polycystic Ovary ◽  
Continuous Light ◽  
Female Rats ◽  
Constant Light ◽  
Surface Epithelium ◽  
Transmission Electron ◽  
Persistent Estrus ◽  
Microscopic Studies ◽  
Pco Syndrome

It is now well established that exposure of cyclic female rats to continuous light induces persistent estrus (PE), a syndrome which in many respects resembles the human polycystic ovary (PCO) syndrome. As in the human PCO, light microscopic studies of cystic ovaries of the constant light rat show numerous atretic follicles, and the surface epithelium grossly appears smooth and white. In the present study, we have utilized scanning (SEM) and transmission electron microscopy (TEM) to study changes on the surface epithelium of PCO in the constant light rat model.

STEROL SYNTHESIS IN RATS WITH EXPERIMENTALLY-INDUCED POLYCYSTIC OVARIES

1967 ◽  
Vol 39 (1) ◽  
pp. 53-60 ◽  
Author(s):  
W. C. ADAMS ◽  
J. H. LEATHEM
Keyword(s):  
Serum Cholesterol ◽  
Total Content ◽  
Gonadal Hormones ◽  
Female Rats ◽  
Cholesterol Concentration ◽  
Sterol Synthesis ◽  
Sterol Metabolism ◽  
Polycystic Ovaries ◽  
Immature Female

SUMMARY Immature female rats were fed thiouracil for 30 days and injected with 10 i.u. human chorionic gonadotrophin (HCG) for the last 20 days. In thiouracil-fed animals, HCG produced large ovaries containing follicular cysts. These ovaries showed a subnormal concentration of cholesterol but both a normal total content and normal incorporation of [1-14C]acetate into digitonin-precipitable-sterols. Liver and serum cholesterol concentrations were reduced, but in vivo, 4 hr. incorporation of acetate into sterols was doubled suggesting either an acceleration of cholesterol turnover or delayed utilization of sterol precursors of cholesterol. HCG also reduced ovarian cholesterol concentration in euthyroid animals but total organ content and incorporation of [14C]acetate were not altered, nor were liver and serum cholesterol affected. Since the effect of induced ovarian cysts on sterol metabolism cannot be accounted for by known effects of thyroid or gonadal hormones it is suggested that influences of steroid hormones on lipid metabolism may be greatly modified in thyroid deficiency.

Capacitation mechanisms, and the role of capacitation as seen in eutherian mammals

1996 ◽  
Vol 8 (4) ◽  
pp. 581 ◽  
Author(s):  
RA Harrison
Keyword(s):  
Cell Death ◽  
Reproductive Tract ◽  
Physiological State ◽  
Hormonal Control ◽  
Female Reproductive Tract ◽  
Functional Heterogeneity ◽  
Vitro Fertilization ◽  
Range Of Functions

Capacitation, the process whereby spermatozoa are rendered capable of interacting with and fertilizing the egg, was discovered more than 40 years ago. However, our understanding of it is still far from satisfactory. Several factors conspire to obfuscate studies of capacitation mechanisms: the inherent functional heterogeneity of sperm populations, the range of functions used as parameters of capacitation (whence the endpoint of the process has become conceptually uncertain), and the several profound differences between model in vitro fertilization (IVF) systems and the situation in vivo in the female reproductive tract. Recent investigations in the author's laboratory have shown that bicarbonate/CO2, an essential component for successful IVF, causes rapid changes in lipid architecture of the sperm plasma membrane and slower changes in surface coating. These changes are accompanied by membrane destabilization and cell death. Evidence suggests that bicarbonate's actions are mediated through cyclic nucleotide signalling. Of particular note is the heterogeneity in rate of response to bicarbonate shown by individual cells in the sperm populations. Taken together with other observations, the findings suggest that capacitation is a series of positive destabilizing events that eventually lead to cell death. The 'capacitated' state would then be a window of destabilization within which spermatozoa can undergo a zona-induced acrosome reaction and display hyperactivated motility. Further along the destabilization pathway, spontaneous acrosome reactions would occur before total membrane degeneration. In vivo, capacitation would be a conflict between destabilization and sperm survival. Concentrations of bicarbonate are maintained low in the cauda epididymidis, where sperm survive for long periods, and one may speculate that hormonal control of local bicarbonate/CO2 in oviducal 'storage' sites in the female tract could allow 'safe' sequestering of live spermatozoa until around the time of ovulation; the environment may then change to produce a 'capacitating' effect, whence, due to the inherent functional heterogeneity of the sequestered population, small numbers of capacitated spermatozoa are released sequentially. In this way, a succession of spermatozoa in the correct physiological state may be provided for the freshly ovulated egg.

Scanning Electron Microscopy of the Polycystic Ovary in Constant Light Rats

1981 ◽  
Vol 39 ◽  
pp. 538-539
Author(s):  
K. B. Singh ◽  
F. K. Khosho
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Polycystic Ovary ◽  
Three Dimensional ◽  
Continuous Light ◽  
Female Rats ◽  
Constant Light ◽  
Sprague Dawley ◽  
Polycystic Ovaries ◽  
Scanning Electron

Exposure of female rats to continuous light eventually induces persistent estrus (PE), a syndrome which in many respects resembles the human polycystic ovary syndrome. Light microscopic studies on the polycystic ovaries of constant light PE rats have been previously reported. In the present study, we have utilized scanning electron microscopy (SEM) to provide information regarding three-dimensional changes occurring on the surface of the polycystic ovary.Following exposure to continuous light for 50 days, PE was induced in a group of Sprague-Dawley female rats according to the procedure described elsewhere (2). Polycystic ovaries from constant light PE rats and ovaries from controls were fixed in 2.5% glutaraldehyde in 0.1M Na cacodylate buffer, pH 7.3 at room temperature for 24 hours. They were then cut into two equal halves along their long axis and fixed for an additional 3-4 hours. The specimens were processed for SEM studies by a modified OTOTO technique, dehydrated and critical point dried with CO2.

TESTOSTERONE Δ4-REDUCTASE ACTIVITY IN RAT LIVER: HORMONAL CONTROL IN VIVO

1974 ◽  
Vol 63 (1) ◽  
pp. 181-189 ◽  
Author(s):  
D. C. PATTERSON ◽  
A. F. CLARK ◽  
C. E. BIRD
Keyword(s):  
Rat Liver ◽  
Reductase Activity ◽  
Enzyme Level ◽  
Hormonal Control ◽  
Female Rats ◽  
Male Rats ◽  
Female Rat ◽  
Rate Limiting Step ◽  
Level Of Activity

SUMMARY The rate-limiting step in the metabolism of testosterone by the liver is reduction of the double bond in ring A. Using a spectrophotometric assay we have studied the effects of some hormonal manipulations on the levels (per mg protein) of testosterone Δ4-reductase activity in rat liver. While the levels of enzyme activity were higher for adult female rat liver than for adult male liver, there were no further changes in livers from female rats at day 15 of gestation. In male rats, castration increased, hypophysectomy decreased and adrenalectomy had no effect on the level of activity. Administration of oestradiol valerate increased the activity in intact and adrenalectomized animals and had no effect in the hypophysectomized or castrated groups. Administration of testosterone enanthate decreased the levels of activity in the castrated and adrenalectomized groups and had no effects in unoperated or hypophysectomized animals. When given together, the two hormones were antagonistic. Prolactin had no significant effects in either intact or hypophysectomized animals. Experiments with actinomycin D and cycloheximide indicated that the synthesis of new protein was involved in the effects of oestradiol in intact rats. All the changes reflected alterations in the microsomal enzyme level.

CONTROL MECHANISMS OF STEROID HORMONE RECEPTORS IN THE REPRODUCTIVE TRACT

1973 ◽  
Vol 74 (Suppl) ◽  
pp. S380-S403 ◽  
Author(s):  
E. Milgrom ◽  
M. Luu Thi ◽  
E. E. Baulieu
Keyword(s):  
Binding Sites ◽  
Hormone Receptors ◽  
Reproductive Tract ◽  
Hormonal Control ◽  
Steroid Hormone Receptors ◽  
Target Cells ◽  
Control Mechanisms ◽  
Target Organs ◽  
Sequential Administration

ABSTRACT The hormonal control of the amount of steroid receptors in the target cells may be a clue for the understanding of hormone receptivity and of integrated hormonal mechanisms (for example cyclic sequences of events). As a model system, the guinea pig uterus progesterone receptor has been studied. After an analysis of the theoretical and practical parameters which should be taken into account in order to measure specifically the receptor binding sites, the protein-RNA synthesis mediated induction of the progesterone receptor by oestradiol is described. The half life of the receptor is about 5 days in hormone deprived animals (in vivo experiments), but in case of progesterone administration it decays very rapidly, due probably to a rise in inactivation rate. Sequential administration of oestradiol and progesterone reproduces the changes observed during the oestrous cycle. The mechanism of the apparent inactivation of the receptor after binding of its own hormonal ligand is unknown. Some information available about the hormonal control of the androgen and oestrogen receptors in their respective target organs is reviewed.

scholarly journals Kisspeptin level in the aging ovary is regulated by the sympathetic nervous system

2017 ◽  
Vol 232 (1) ◽  
pp. 97-105 ◽  
Author(s):  
Daniela Fernandois ◽  
Gonzalo Cruz ◽  
Eun Kyung Na ◽  
Hernán E Lara ◽  
Alfonso H Paredes
Keyword(s):  
Adrenergic Receptor ◽  
Follicular Development ◽  
Sympathetic Nerves ◽  
Female Rats ◽  
Reproductive Aging ◽  
Beta Adrenergic Receptor ◽  
Beta Adrenergic ◽  
Primordial Follicles ◽  
Follicular Cyst

Previous work has demonstrated that the increase in the activity of sympathetic nerves, which occurs during the subfertility period in female rats, causes an increase in follicular cyst development and impairs follicular development. In addition, the increase in ovarian sympathetic activity of aged rats correlates with an increased expression of kisspeptin (KISS1) in the ovary. This increase in KISS1 could participate in the decrease in follicular development that occurs during the subfertility period. We aimed to determine whether the blockade of ovarian sympathetic tone prevents the increase in KISS1 expression during reproductive aging and improves follicular development. We performed 2 experiments in rats: (1) an in vivo blockade of beta-adrenergic receptor with propranolol (5.0 mg/kg) and (2) an ovarian surgical denervation to modulate the sympathetic system at these ages. We measured Kisspeptin and follicle-stimulating hormone receptor (FSHR) mRNA and protein levels by qRT-PCR and western blot and counted primordial, primary and secondary follicles at 8, 10 and 12 months of age. The results showed that ovarian KISS1 decreased but FSHR increased after both propranolol administration and the surgical denervation in rats of 8, 10 and 12 months of age. An increase in FSHR was related to an increase in the number of smaller secondary follicles and a decreased number of primordial follicles at 8, 10 and 12 months of age. These results suggest that intraovarian KISS1 is regulated by sympathetic nerves via a beta-adrenergic receptor and participates locally in ovarian follicular development in reproductive aging.

scholarly journals A New Symmetrical Thiazolidinedione Derivative: In Silico Design, Synthesis, and In Vivo Evaluation on a Streptozotocin- Induced Rat Model of Diabetes

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1294
Author(s):  
Samuel Álvarez-Almazán ◽  
Gabriel Navarrete-Vázquez ◽  
Itzia Irene Padilla-Martínez ◽  
José Correa-Basurto ◽  
Diana Alemán-González-Duhart ◽  
...  
Keyword(s):  
Rat Model ◽  
In Silico ◽  
Female Rats ◽  
Therapeutic Effects ◽  
Acute Oral Toxicity ◽  
Oral Toxicity ◽  
In Vivo Evaluation ◽  
Docking Simulations ◽  
Ppar Γ

By activating PPAR-γ, thiazolidinediones normalize glucose levels in animal models of type 2 diabetes and in patients with this pathology. The aim of the present study was to analyze 219 new derivatives in silico and select the best for synthesis, to be evaluated for acute oral toxicity in female rats and for control of diabetes-related parameters in a rat model of streptozotocin-induced diabetes. The best compound was chosen based on pharmacokinetic, pharmacodynamic, and toxicological parameters obtained in silico and binding orientation observed by docking simulations on PPAR-γ. Compound 1G was synthesized by a quick and easy Knoevenagel condensation. Acute oral toxicity was found at a dose greater than 2000 mg/Kg. Compound 1G apparently produces therapeutic effects similar to those of pioglitazone, decreasing glycaemia and triglyceride levels in diabetic animals, without liver damage. Moreover, it did not cause a significant weight gain and tended to reduce polydipsia and polyphagia, while diminishing systemic inflammation related to TNF-α and IL-6. It lowered the level of endogenous antioxidant molecules such as reduced glutathione and glutathione reductase. In conclusion, 1G may be a candidate for further testing as an euglycemic agent capable of preventing the complications of diabetes.

scholarly journals Treatment of dental plaque biofilms using photodynamic therapy: a randomised controlled study

2021 ◽  
Author(s):  
A. Alsaif ◽  
J. F. Tahmassebi ◽  
S. R. Wood
Keyword(s):  
Photodynamic Therapy ◽  
Incubation Time ◽  
Dental Plaque ◽  
Continuous Light ◽  
Laser Scanning Microscopy ◽  
Controlled Study ◽  
Bacterial Counts ◽  
Randomised Controlled Study ◽  
Randomised Controlled

Abstract Introduction Photodynamic therapy (PDT) is a treatment modality involving a dye that is activated by exposure to light of a specific wavelength in the presence of oxygen to form oxygen species causing localised damage to microorganisms. Aim To determine the most effective bactericidal incubation and irradiation times of erythrosine-based PDT on in vivo-formed dental plaque biofilms. Methods A randomised controlled study; 18-healthy adult participants wearing intraoral appliances with human enamel slabs to collect dental plaque samples in two separate periods of two weeks each for use in arm-1 and arm-2. These accumulated dental plaque samples were treated with PDT under different experimental conditions. Incubation times with photosensitiser (erythrosine) of 15 min and 2 min were used in arm-1 and arm-2, respectively, followed by light irradiation for either 15 min (continuous) or as a fractionated dose (5 × 30 sec). Following treatment, percentage reductions of total bacterial counts were compared between the different groups. In addition, confocal laser scanning microscopy (CLSM) and LIVE/DEAD® BacLight™ Bacterial Viability Kit were used to visualise the effect of PDT on in vivo-formed biofilms. Results Significant reductions in the percentage of total bacterial counts (~93–95%) of in vivo-formed biofilms were found when using either 2 min or 15min incubation times and applying 15 min continuous light. Although when applying fractionated light, there was more cell death when 15 min incubation time was used (~ 91%) compared with the 2 min incubation time (~ 64%). CLSM results supported these findings. Conclusion Improving the clinical usefulness of PDT by reducing its overall treatment time seems to be promising and effective in killing in vivo-formed dental plaque biofilms.

Effects of in vivo gonadal hormone environment on in vitro hGRF-40-stimulated GH release

1985 ◽  
Vol 249 (3) ◽  
pp. E276-E280 ◽  
Author(s):  
W. S. Evans ◽  
R. J. Krieg ◽  
E. R. Limber ◽  
D. L. Kaiser ◽  
M. O. Thorner
Keyword(s):  
Female Rats ◽  
Male Rats ◽  
Gonadal Hormone ◽  
Base Line ◽  
Pituitary Cells ◽  
Intact Male ◽  
Castrate Male ◽  
Basal Release

The effects of gender and the gonadal hormone environment on basal and stimulated growth hormone (GH) release by dispersed and continuously perifused rat anterior pituitary cells were examined. Cells from intact male and diestrus day 2 female rats and from castrate male rats either untreated or treated with testosterone (T) or 17 beta-estradiol (E2) were used. Basal GH release (ng/min per 10(7) cells; mean +/- SE) by cells from diestrus day 2 female rats was less than by cells from castrate rats treated with T (4.3 +/- 0.6 vs. 11.4 +/- 2.7, respectively; P less than 0.025). No other differences in basal release were detected. Concentration-response relationships were documented between human GH-releasing factor 40 (hGRF-40; 0.03-100 nM given as 2.5-min pulses every 27.5 min) and GH release. Mean (+/- SE) overall GH release (ng/min per 10(7) cells) above base line was greater by cells from intact male rats (496 +/- 92) than by cells from castrate (203 +/- 37.3; P less than 0.0001), castrate and T-treated (348 +/- 52.8; P = 0.008), or castrate and E2-treated (58.1 +/- 6.8; P less than 0.001) male rats or by diestrus day 2 rats (68.6 +/- 9.5; P = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

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