BACKGROUND/AIMS: The ewe is increasingly being used as an animal model for pelvic floor disorders. The aim was to further characterize changes in the vaginal properties during its entire lifespan. METHODS: Vaginal tissues were collected at different stages of reproductive life (neonatal, prepubescence, nulliparous, primiparous, multiparous, and menopausal; ≥6 ewes/group). Vaginal size, as well as active and passive biomechanics, was measured. Microscopy included thickness of glycogen, epithelium, lamina propria and muscularis thickness, densities of collagen, elastin, smooth muscle, and nerves. RESULTS: Vaginal dimensions increase during adolescence, peak at reproductive levels, and decrease sharply after ovariectomy. One year after first delivery, the distal vagina gets more compliant, yet this is reversed later in life. The thickness of glycogen staining epithelial layers changed with puberty and menopause. The epithelium was markedly thicker after multiple deliveries. The thickness of lamina propria and muscularis increased in puberty and in nulliparous. Semi-quantitative collagen assessment demonstrated a lower collagen and higher elastin content after first and multiple deliveries. CONCLUSION: The changes in the ovine vaginal wall during representative moments of her lifespan parallel those observed in women.

• Klíčová slova
• Biomechanics, Delivery, Genital tract, Menopause, Reproduction, Sheep, Vagina,
• MeSH
• dlouhověkost fyziologie   MeSH
• menopauza fyziologie   MeSH
• modely u zvířat MeSH
• ovarektomie MeSH
• ovce MeSH
• parita fyziologie   MeSH
• rozmnožování fyziologie   MeSH
• těhotenství MeSH
• vagina anatomie a histologie   fyziologie   MeSH
• zvířata MeSH
• Check Tag
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

INTRODUCTION AND HYPOTHESIS: Animal models are useful for investigating the genesis of pelvic floor dysfunction and for developing novel therapies for its treatment. There is a need for an alternative large-animal model to the nonhuman primate. Therefore we studied the effects of the first vaginal delivery, ovariectomy and systemic hormonal replacement therapy (HRT) on the biomechanical and structural properties of the ovine vagina. METHODS: We examined the gross anatomical properties of nulliparous, primiparous, ovariectomized multiparous, and ovariectomized hormone-replaced multiparous sheep (six animals per group). We also harvested mid-vaginal and distal vaginal tissue to determine smooth muscle contractility and passive biomechanical properties, for morphometric assessment of the vaginal wall layers, to determine collagen and elastin content, and for immunostaining for α-smooth muscle actin and estrogen receptor-α. RESULTS: There were no regional differences in the nulliparous vagina. One year after the first vaginal delivery, stiffness and contractility of the distal vagina were decreased, whereas the elastin content increased. The mid-vagina of ovariectomized sheep was stiff, and its epithelium was thin and lacked glycogen. HRT decreased the stiffness of the mid-vagina by 45% but had no measurable effect on contractility or elastin content, and increased epithelial thickness and glycogen content. HRT also increased the epithelial thickness and glycogen content of the distal vagina. At this location, there were no changes in morphology or stiffness. CONCLUSION: In sheep, life events including delivery and ovariectomy affect the biomechanical properties of the vagina in a region-specific way. Vaginal delivery mainly affects the distal region by decreasing stiffness and contractility. HRT can reverse the increase in stiffness of the mid-vagina observed after surgical induction of menopause. These observations are in line with scanty biomechanical measurements in comparable clinical specimens.

• Klíčová slova
• Animal model, Biomechanics, Contractility, Sheep vagina, Vaginal delivery,
• MeSH
• aktiny metabolismus   MeSH
• alfa receptor estrogenů metabolismus   MeSH
• biomechanika MeSH
• elastin metabolismus   MeSH
• epitel metabolismus   patologie   MeSH
• glykogen metabolismus   MeSH
• hladké svalstvo patofyziologie   MeSH
• hormonální substituční terapie MeSH
• kolagen metabolismus   MeSH
• modely nemocí na zvířatech MeSH
• onemocnění dna pánevního etiologie   MeSH
• ovarektomie škodlivé účinky   MeSH
• ovce MeSH
• parita MeSH
• porod * MeSH
• svalová kontrakce MeSH
• vagina patologie   patofyziologie   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• ACTA2 protein, human MeSH Prohlížeč
• aktiny MeSH
• alfa receptor estrogenů MeSH
• elastin MeSH
• glykogen MeSH
• kolagen MeSH

OBJECTIVE: We aimed to characterize the effect of vaginal or abdominal mesh insertion and of different collagen augmentation of polypropylene mesh in a sheep model. Outcome measures were passive and active biomechanical properties and semiquantitative morphometry. STUDY DESIGN: Forty-two Texel sheep were used: 6 were nonimplanted controls (n = 6), the rest were implanted with polypropylene mesh (n = 12; Avaulta Solo; Bard Medical, Covington, GA) or collagen-coated meshes: Avaulta Plus (n = 12; Bard Medical) and Ugytex (n = 12; Sofradim International, Trevoux, France). Through a single incision, the rectovaginal septum was dissected and a 35 × 35-mm mesh was sutured to the underlying tissues. Abdominally, a 50 × 50-mm mesh was laid over a primarily sutured full thickness 40-mm longitudinal incisional defect. Animals were explanted after 60 or 180 days (n = 6 per group). Outcome measures were passive biomechanics by biaxial tensiometry, active contractility of vaginal explants, and histologic evidence. RESULTS: Vaginal explants were 2.4 times stiffer compared with native vaginal tissue (P < .001), but without differences in comfort zone stiffness or slope of the load-elongation in the physiologic range between the products that were tested. Collagen coating was associated with a 16-fold reduction in contractile force at 180 days, compared with native vaginal tissue, both for Avaulta Plus (P = .032) and Ugytex (P = .015). Abdominal explants were 1.3-times stiffer compared with native abdominal wall tissue (P < .001) and were 1.9-times stiffer compared with vaginal explants. CONCLUSION: Vaginal mesh implantation yields less stiff explants compared with abdominal explants. Vaginal mesh implantation also alters the passive and active biomechanical properties compared with native vaginal tissues. Collagen matrices did not reduce the number of graft-related complications.

• Klíčová slova
• biomechanics, collagen, contractility, mesh, sheep,
• MeSH
• biomechanika MeSH
• břišní stěna patologie   chirurgie   MeSH
• chirurgické síťky * MeSH
• kolagen * MeSH
• ovce MeSH
• polypropyleny * MeSH
• pooperační komplikace etiologie   MeSH
• vagina patologie   chirurgie   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• kolagen * MeSH
• polypropyleny * MeSH

OBJECTIVE: A short literature review of ewe as an experimental model in research of effects of pregnancy, delivery and urogynecological surgical procedures on the pelvic floor. DESIGN: Literature overview. SETTING: Institute for the Care of Mother and Child, Third Faculty of Medicine, Prague. METHODS: This is an overview of recent literature on experiments using ewes as a model for biomechanical and morphological changes of the vagina induced by pregnancy, delivery and transvaginal graft implantation. RESULTS AND CONCLUSION: The ovine pelvic floor and vagina have comparable morphology to human. Its biomechanical and biochemical properties get changed during the pregnancy and postpartum similarly to clinical findings. Sheep could be used for testing of urogynaecological implants vaginally and simultaneously implanted in the abdominal wall to provide better understanding of anatomical environment differences. The size of the ovine vagina gives the opportunity to perform comprehensive biomechanical, histological and biochemical testing. Experiments and observation may improve our understanding of pathology and physiology of vaginal wall changes induced by hormones, prolapse or surgery.

• Klíčová slova
• pelvic floor, sheep effects of pregnancy and delivery.,
• MeSH
• gynekologické chirurgické výkony MeSH
• modely u zvířat * MeSH
• ovce * MeSH
• pánevní dno chirurgie   MeSH
• poporodní období MeSH
• těhotenství * MeSH
• urologické chirurgické výkony MeSH
• vagina chirurgie   MeSH
• vedení porodu * MeSH
• zvířata MeSH
• Check Tag
• těhotenství * MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

OBJECTIVE: To evaluate the host- and biomechanical response to a fully absorbable poly-4-hydroxybutyrate (P4HB) scaffold in comparison with the response to polypropylene (PP) mesh. DESIGN: In vivo animal experiment. SETTING: KU Leuven Center for Surgical Technologies. POPULATION: Fourteen parous female Mule sheep. METHODS: P4HB scaffolds were surgically implanted in the posterior vaginal wall of sheep. The comparative PP mesh data were obtained from an identical study protocol performed previously. MAIN OUTCOME MEASURES: Gross necropsy, host response and biomechanical evaluation of explants, and the in vivo P4HB scaffold degradation were evaluated at 60- and 180-days post-implantation. Data are reported as mean ± standard deviation (SD) or standard error of the mean (SEM). RESULTS: Gross necropsy revealed no implant-related adverse events using P4HB scaffolds. The tensile stiffness of the P4HB explants increased at 180-days (12.498 ± 2.66 N/mm SEM [p =0.019]) as compared to 60-days (4.585 ± 1.57 N/mm) post-implantation, while P4HB degraded gradually. P4HB scaffolds exhibited excellent tissue integration with dense connective tissue and a moderate initial host response. P4HB scaffolds induced a significantly higher M2/M1 ratio (1.70 ± 0.67 SD, score 0-4), as compared to PP mesh(0.99 ± 0.78 SD, score 0-4) at 180-days. CONCLUSIONS: P4HB scaffold facilitated a gradual load transfer to vaginal tissue over time. The fully absorbable P4HB scaffold, in comparison to PP mesh, has a favorable host response with comparable load-bearing capacity. If these results are also observed at longer follow-up in-vivo, a clinical study using P4HB for vaginal POP surgery may be warranted to demonstrate efficacy. TWEETABLE ABSTRACT: Degradable vaginal P4HB implant might be a solution for treatment of POP.

• Klíčová slova
• biomechanics, degradable scaffold, host response, pelvic organ prolapse, poly-4-hydroxybutyrate, vaginal surgery,
• MeSH
• biomechanika MeSH
• chirurgické síťky * škodlivé účinky   MeSH
• hydroxybutyráty MeSH
• lidé MeSH
• ovce MeSH
• polypropyleny * MeSH
• vagina chirurgie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• hydroxybutyráty MeSH
• polypropyleny * MeSH

Variability of the endometrium thickness and surface epithelium in sheep after the effect of 20 mg of chlorsuperlutin (vaginal swabs soaked in this preparation) was studied. The results obtained demonstrate that at the estrus synchronization by means of the above mentioned preparation similar changes of the endometrium can be observed as those at the estrus without controlled sexual activity. It was found out that the variability of the endometrium thickness, both in cows and heifers, depended on the follicle-stimulating hormone evoking mucosal edematization in view of the phase of the cycle when the ovulation-inhibiting factor came into play. The endometrium thickness of 1499.5 mu on an average was found in sheep with synchronized estrus, and the epithelium thickness was, on an average, 24.7 mu. We observed, according to the results of the experiment, that the endometrium thickness varied even in a given animal; the changes were the same on the endometrium of both horns of uterus independent of the ovary showing cyclical changes. The endometrium gets thinner towards to oviduct, its thickness not being uniform in individual parts of uterus. The results can be distorted due to some artificial factors, e.g. the way of sampling, fixating media, etc. Nevertheless, an assessment of the variability of the endometrium thickness belongs to objective methods to examine the functional activity of ovaries and to find out the state of uterine mucosa.

• MeSH
• corpus luteum účinky léků   MeSH
• cyproteron farmakologie   MeSH
• endometrium účinky léků   MeSH
• estrus účinky léků   MeSH
• kontraceptiva farmakologie   MeSH
• ovce * MeSH
• těhotenství MeSH
• vagina účinky léků   MeSH
• zvířata MeSH
• Check Tag
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• cyproteron MeSH
• kontraceptiva MeSH

• MeSH
• elektrofyziologie MeSH
• estrus * MeSH
• kozy fyziologie   MeSH
• ovce fyziologie   MeSH
• sliznice fyziologie   MeSH
• těhotenství u zvířat MeSH
• těhotenství MeSH
• vagina fyziologie   MeSH
• zvířata MeSH
• Check Tag
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: There is an urgent need to develop better materials to provide anatomical support to the pelvic floor without compromising its function. OBJECTIVE: Our aim was to assess outcomes after simulated vaginal prolapse repair in a sheep model using three different materials: (1) ultra-lightweight polypropylene (PP) non-degradable textile (Restorelle) mesh, (2) electrospun biodegradable ureidopyrimidinone-polycarbonate (UPy-PC), and (3) electrospun non-degradable polyurethane (PU) mesh in comparison with simulated native tissue repair (NTR). These implants may reduce implant-related complications and avoid vaginal function loss. DESIGN, SETTING, AND PARTICIPANTS: A controlled trial was performed involving 48 ewes that underwent NTR or mesh repair with PP, UPy-PC, or PU meshes (n=12/group). Explants were examined 60 and 180 d (six per group) post-implantation. INTERVENTION: Posterior rectovaginal dissection, NTR, or mesh repair. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Implant-related complications, vaginal contractility, compliance, and host response were assessed. Power calculation and analysis of variance testing were used to enable comparison between the four groups. RESULTS: There were no visible implant-related complications. None of the implants compromised vaginal wall contractility, and passive biomechanical properties were similar to those after NTR. Shrinkage over the surgery area was around 35% for NTR and all mesh-augmented repairs. All materials were integrated well with similar connective tissue composition, vascularization, and innervation. The inflammatory response was mild with electrospun implants, inducing both more macrophages yet with relatively more type 2 macrophages present at an early stage than the PP mesh. CONCLUSIONS: Three very different materials were all well tolerated in the sheep vagina. Biomechanical findings were similar for all mesh-augmented repair and NTR. Constructs induced slightly different mid-term inflammatory profiles. PATIENT SUMMARY: Product innovation is needed to reduce implant-related complications. We tested two novel implants, electrospun and an ultra-lightweight polypropylene textile mesh, in a physiologically relevant model for vaginal surgery. All gave encouraging outcomes.

• Klíčová slova
• Biocompatibility, Biomaterials, Biomechanics, Pelvic organ prolapse, Vaginal surgery,
• MeSH
• biokompatibilní materiály MeSH
• chirurgické síťky * MeSH
• gynekologické chirurgické výkony MeSH
• modely nemocí na zvířatech MeSH
• modely u zvířat MeSH
• ovce MeSH
• polypropyleny * MeSH
• prolaps dělohy chirurgie   MeSH
• protézy - design MeSH
• pyrimidinony MeSH
• testování materiálů MeSH
• textilie MeSH
• výsledek terapie MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• Názvy látek
• biokompatibilní materiály MeSH
• polypropyleny * MeSH
• pyrimidinony MeSH
• ureidopyrimidinone MeSH Prohlížeč

OBJECTIVE: To evaluate the effect of iatrogenic menopause on the physiology of the vagina of the ewe and to evaluate if vaginal changes in ewes can be translated to women with genitourinary syndrome of menopause (GSM). METHODS: Preclinical research with Dohne Merino ewes. Iatrogenic menopause was induced by bilateral ovariectomy (OVX). Animals were randomized for surgery, blinded for allocation and outcome assessment. Differences between groups were determined by linear regression analyses at 5 months after OVX. Outcome measures were vaginal epithelial thickness, pH, vaginal maturation value, vaginal maturation index, epithelial glycogen accumulation, content of elastin fibers, collagen, and vascularity. RESULTS: OVX ewes (n = 20) showed epithelial thinning of the vaginal wall from 146 μm to 47 μm (mean, P < 0.001). Furthermore, epithelial glycogen accumulation and vascularity of the vaginal wall significantly decreased (43% and 23%, respectively) as compared with the control group (no intervention; n = 5). No significant differences were found for other outcome measures. CONCLUSION: This study established the ewe as a suitable large animal model for GSM. Furthermore, the similar relevant outcomes in humans and ewes hold great value for future translational research for the evaluation and optimization of different treatment modalities for GSM.

• Klíčová slova
• atrophy, ewe, genitourinary syndrome of menopause, model, ovariectomy,
• MeSH
• glykogen MeSH
• iatrogenní nemoci MeSH
• lidé MeSH
• menopauza * MeSH
• modely u zvířat MeSH
• ovarektomie škodlivé účinky   MeSH
• ovce MeSH
• vagina * chirurgie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• glykogen MeSH

The effects were investigated of a hormonal preparation of serum gonadotrophin (SC) on neurosecretion, PAS-positive mucopolysaccharides and on histological changes in the third cerebral ventricle; at the same time variations were determined of catecholamine concentrations of ependyma surface in the hypothalamic regions that control directly reproductive functions in ewes of the Merino and Wallachian breeds in the oestrus period. Ewe oestrus was synchronized by insertion of Ageline (Spofa) sponges into the vagina. A dose of 2000 IU of serum gonadotrophin (Bioveta, Ivanovice in Haná) was administered to stimulate the ewes (n = 30). Twelve ewes of the Wallachian breed, six control and six test ones, were used for radioenzymatic detection of catecholamines (Catechola test, Prague). The brains were segmented immediately after bleeding and samples were taken from the eminentia medialis, area preoptica and corpus mamillare pursuant to the stereotactic configuration of the sheep hypothalamus (Welento et al., 1968). The brains of ten ewes of the Merino breed, four control and six test ones, and of eight ewes of the Wallachian breed (four control and four test ones) were used for histological treatment. For the purposes of a histological study, the brains were treated with current histological methods. The amount of neurosecretory material was assessed by light microscopy (Nakahara, 1963). Samples for the study of ependyma of the lower part of the third cerebral ventricle were examined in a scanning electron microscope. The obtained results demonstrate a statistically significant decrease by 36.4% (P less than 0.05) in epinephrin concentrations in the area preoptica of hypothalamus after SG administration (Fig. 3), in comparison with the control group. A decrease in norepinephrin concentration in the corpus mamillare (Fig. 4) was statistically significant (P less than 0.001). The dose of 2000 IU SG influenced most markedly catecholamine concentrations in the eminentia medialis (Fig. 5), where a statistically significant decrease in epinephrin and norepinephrin concentration was observed (P less than 0.01). Dopamine concentrations also decreased significantly (P less than 0.05) in the eminentia medialis (Fig. 5). Following the hormonal stimulation, a significant increase in dopamine and epinephrin concentrations was observed in the hypophysis of sheep (Fig. 6; P less than 0.05) and in the epiphysis there was a significant decrease in epinephrin and dopamine concentration (P less than 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)

• MeSH
• gonadotropiny farmakologie   MeSH
• hypothalamus účinky léků   metabolismus   ultrastruktura   MeSH
• katecholaminy metabolismus   MeSH
• ovce metabolismus   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• gonadotropiny MeSH
• katecholaminy MeSH