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Female Rabbits (female + rabbits)
Selected AbstractsContractile Changes of the Clitoral Cavernous Smooth Muscle in Female Rabbits with Experimentally Induced Overactive BladderTHE JOURNAL OF SEXUAL MEDICINE, Issue 5 2008Soon-Chul Myung MD ABSTRACT Introduction., Recently, growing clinical evidence has suggested that sexual dysfunction is more prevalent in women with overactive bladder (OAB). Aims., However, there has been no basic research to clarify the relationship between OAB and female sexual dysfunction. Therefore, we investigated this issue using a rabbit model of OAB. Methods., Twenty-seven New Zealand white female rabbits were randomly divided into the OAB and control groups. Main Outcome Measures., The contractile responses of clitoral cavernous strips to K+, phenylephrine (PE), Bay K 8644, and endothelin (ET)-1, and the relaxation responses of acetylcholine (ACh), sodium nitroprusside (SNP), and Y-27632 to PE-induced contraction by measuring isometric tension. Results., The contractile responses to K+, PE, Bay K 8644, and ET-1 were significantly more increased in the OAB group in a dose-dependant manner than in the control group (P < 0.05), and the responses to ET-1 were more prominent than those to the remaining substances (P < 0.01). The increased contractile responses to ET-1 were blocked by BQ123 (ETA receptor antagonist) but not by BQ788 (ETB receptor antagonist). Clitoral cavernosal strips from the OAB group were more difficult to relax than those from the control group in terms of ACh- and SNP-induced relaxation (P < 0.05). The Y-27632-induced relaxant responses to PE- and ET-1-induced contraction were less prominent in the OAB group than in the control group. Conclusions., The results of this study provide evidence that female OAB may deteriorate clitoral engorgement, which is associated with a greater force generation by increased calcium sensitization and subsequently decreased of relaxation. The activation of ET and Rho-kinase system may be crucial to negatively effect the clitoral smooth muscle relaxation in experimentally induced OAB animal model. But whether these vasomotor effects are revived in human clitoris is still debatable. Myung S-C, Lee M-Y, Lee S-Y, Yum S-H, Park S-H, and Kim S-C. Contractile changes of the clitoral cavernous smooth muscle in female rabbits with experimentally induced overactive bladder. J Sex Med 2008;5:1088,1096. [source] Percutaneous toxicokinetic and repeated cutaneous contact studies with ethylene glycol monohexyl etherJOURNAL OF APPLIED TOXICOLOGY, Issue 5 2003Bryan Ballantyne Abstract Ethylene glycol monohexyl ether (EGHE; CAS no. 112-54-4) is a liquid industrial chemical with a potential for skin contact. The toxicokinetics of EGHE was investigated in Fischer 344 rats and New Zealand White rabbits by intravenous (i.v.) and 48-h occluded epicutaneous dosing. Given i.v. to male rats (2.5,25 mg kg,1) [14C]EGHE demonstrated ,rst-order kinetics. Carbon-14 was eliminated mainly in urine (68,74%) as metabolites, with no free EGHE. The plasma free EGHE concentration declined rapidly post-dosing and was not detectable by 8 h. Similar results were obtained for [14C]EGHE given i.v. to male rabbits in the dosage range 1,10 mg kg,1, except that the metabolism of EGHE was more rapid, with no free EGHE being detectable in plasma by 1 h post-dosing. After cutaneous dosing of male and female rats with 25 mg kg,1, there was rapid percutaneous absorption, with >95% of the radiochemical dose being recovered. Percutaneous bioavailability was >75%. Carbon-14 was excreted in urine (21,33%) to a lesser extent than by the i.v. route, and 14CO2 and volatiles accounted for 15,18%. Carbon-14 recovery was low from tissues and organs (0.39,0.46%), with no preferential accumulation. Extensive metabolism was indicated by the rapid decline in plasma free EGHE, with none being detectable by 48 h. Free EGHE was not present in urine, and urinary radioactivity was associated with up to seven metabolites. After cutaneous dosing of male and female rabbits (10 mg kg,1) ca. 75% of the dose was recovered, most 14C being in urine (58,60%). Urine radioactivity was associated with up to nine metabolite peaks, but no free EGHE. The toxicokinetic ,ndings indicate a signi,cant percutaneous absorption of EGHE across both rat and rabbit skin, which is rapidly and extensively metabolized, with renal excretion being the principal route of elimination of metabolites. A 9-day repeated skin contact study in the male and female New Zealand White rabbit, using a dosage range of 44,444 mg kg,1 day,1, did not show any evidence for percutaneous systemic toxicity. Copyright © 2003 John Wiley & Sons, Ltd. [source] Morphology of Reproductive Organs, Semen Quality and Sexual Behaviour of the Male Rabbit Exposed to a Soy-containing Diet and Soy-derived Isoflavones during Gestation and LactationREPRODUCTION IN DOMESTIC ANIMALS, Issue 6 2009JR Cardoso Contents Placental and breastfeeding transfer of soy isoflavones are potential routes for animal and human exposure to phytoestrogens, and reproductive dysfunctions have been linked to early exposure to these compounds. So, the aim of this study was to investigate the effects of perinatal (intrauterine and lactational) exposure to soy-containing diet and soy-derived isoflavones on the reproductive parameters of male rabbits. For this purpose, 12 female rabbits were randomly assigned to receive: (1) a soy- and alfalfa-free diet (control diet); (2) a soy- and alfalfa-free diet supplemented with 10 mg/kg body wt/day of soy isoflavones; (3) a soy- and alfalfa-free diet supplemented with 20 mg/kg body wt/day of soy isoflavones; and (4) a diet containing 18% of soy meal, throughout gestation and lactation. Weight and morphology of the reproductive organs of some of the male offspring were evaluated at weaning (between days 29 and 31). The remaining males were placed on the control diet from weaning to adulthood (gestational and lactational exposure only). Sexual behaviour, semen quality and reproductive organs' morphology were evaluated after puberty. There were no significant differences in litter size and gestation duration between control and treatment groups. Perinatal exposure to soy-containing diet and soy isoflavones did not alter testis, epididymides, proprostate and prostate weight and gross morphology. After puberty, sexual behaviour and semen parameters did not differ significantly from the control group. These results indicate that intrauterine and lactational exposure to soy-containing diet and soy-derived isoflavones may not adversely affect reproductive development and function of male rabbits. [source] Contractile Changes of the Clitoral Cavernous Smooth Muscle in Female Rabbits with Experimentally Induced Overactive BladderTHE JOURNAL OF SEXUAL MEDICINE, Issue 5 2008Soon-Chul Myung MD ABSTRACT Introduction., Recently, growing clinical evidence has suggested that sexual dysfunction is more prevalent in women with overactive bladder (OAB). Aims., However, there has been no basic research to clarify the relationship between OAB and female sexual dysfunction. Therefore, we investigated this issue using a rabbit model of OAB. Methods., Twenty-seven New Zealand white female rabbits were randomly divided into the OAB and control groups. Main Outcome Measures., The contractile responses of clitoral cavernous strips to K+, phenylephrine (PE), Bay K 8644, and endothelin (ET)-1, and the relaxation responses of acetylcholine (ACh), sodium nitroprusside (SNP), and Y-27632 to PE-induced contraction by measuring isometric tension. Results., The contractile responses to K+, PE, Bay K 8644, and ET-1 were significantly more increased in the OAB group in a dose-dependant manner than in the control group (P < 0.05), and the responses to ET-1 were more prominent than those to the remaining substances (P < 0.01). The increased contractile responses to ET-1 were blocked by BQ123 (ETA receptor antagonist) but not by BQ788 (ETB receptor antagonist). Clitoral cavernosal strips from the OAB group were more difficult to relax than those from the control group in terms of ACh- and SNP-induced relaxation (P < 0.05). The Y-27632-induced relaxant responses to PE- and ET-1-induced contraction were less prominent in the OAB group than in the control group. Conclusions., The results of this study provide evidence that female OAB may deteriorate clitoral engorgement, which is associated with a greater force generation by increased calcium sensitization and subsequently decreased of relaxation. The activation of ET and Rho-kinase system may be crucial to negatively effect the clitoral smooth muscle relaxation in experimentally induced OAB animal model. But whether these vasomotor effects are revived in human clitoris is still debatable. Myung S-C, Lee M-Y, Lee S-Y, Yum S-H, Park S-H, and Kim S-C. Contractile changes of the clitoral cavernous smooth muscle in female rabbits with experimentally induced overactive bladder. J Sex Med 2008;5:1088,1096. [source] Effect of systemic administration of nicotine on healing in osseous defects.CLINICAL ORAL IMPLANTS RESEARCH, Issue 5 2006An experimental study in rabbits. Abstract Objectives: The aim of the present study was to analyze the effect of systemic administration of nicotine on bone healing in osseous defects in the tibia of rabbits. Material and methods: Sixteen female rabbits received nicotine (n=8; test group) or saline (n=8; control group) via subcutaneously placed mini-osmotic pumps for 8 weeks. The animals underwent three surgical operations during the experimental period, and body weight was registered weekly. Blood samples were collected to determine cotinine and prostaglandin E2 levels. Bone preparations were made in the right leg of all rabbits after 4 weeks and in the left leg after 6 weeks of nicotine/placebo exposure. Thus, 2- and 4-week healing groups were created for the bone defects. After 8 weeks, the animals were killed. Tissue blocks including the bone defects were prepared for histological analysis. Results: The animals in the test group lost weight, while the control group gained weight during the experiment. The prostaglandin E2 levels in plasma increased significantly following nicotine exposure in the test group. No significant differences in the percentage of vessels and bone density in the osseous defects were found between the test and the control groups after 2 and 4 weeks of healing. Conclusions: In this experiment, systemic administration of nicotine over 4 or 6 weeks, respectively, influenced body weight and systemic prostaglandin E2 levels but not the amount of blood vessels and the bone mineral density in bone defects after 2 or 4 weeks of healing. [source] The impact of nicotine on bone healing and osseointegrationCLINICAL ORAL IMPLANTS RESEARCH, Issue 3 2005An experimental study in rabbits Abstract Objectives: To examine the short-term effect of nicotine on bone healing and osseointegration. Material and methods: Sixteen female rabbits were divided into two groups. The test group was exposed to nicotine tartrate for 8 weeks and the control group was exposed to placebo. Nicotine or placebo was administered via a miniosmotic pump and plasma cotinine levels were measured weekly. The pump delivered 15 mg of nicotine/day for the animals in the test group. All rabbits had three tibial bone preparations. In the proximal and distal bone bed, implants were placed after 4 weeks (right tibia) and after 6 weeks (left tibia). Thus, 2- and 4-week healing groups were created. Removal torque test (RMT) was performed at the distal implants. Ground sections were made from the proximal and the central bone beds. The fraction of mineralized bone in contact to the implant (BIC) and the bone density within the implant threads (BD-i) were determined for the bone,implant specimens. For the central bone beds without implants the bone density (BD-c) in the bone defects was determined. Results: No significant difference in RMT values was found between the test and the control group. Histomorphometric measurements of the BIC and the peri-implant BD-i showed no significant differences between the test and the control group after 2 or 4 weeks. Significant differences were, however, found between the 2- and 4-week samples. In the central bone beds, there was no significant difference in BD-c between the test and the control group. Conclusion: Nicotine exposure in a short period of time did not have a significant impact on bone healing or implant osseointegration in rabbits. Résumé Le but de l'étude a été d'examiner l'effet à court terme de la nicotine sur la guérison osseuse et l'ostéoïntégration. Seize lapines ont été réparties en deux groupes. Le groupe test était exposé au tartrate de nicotine durant huit semaines et le groupe contrôle était exposé au placebo. La nicotine et le placebo étaient administrés par une pompe miniosmotique et les teneurs de cotinine plasmatique étaient mesurées chaque semaine. La pompe distillait 15 mg de nicotine par jour pour les animaux du groupe test. Toutes les lapines avaient trois préparations osseuses. Dans le lit osseux proximal et distal, les implants étaient placés après quatre semaines (tibia droit) et six semaines (tibia gauche) Des groupes de guérison de deux et de quatre semaines ont ainsi été créés. Des tests de torsion à l'enlèvement ont été effectués au niveau des implants distaux. Des coupes ont été effectuées pour les lits osseux centraux et proximaux. La fraction d'os minéralisé en contact avec l'implant et la densité osseuse à l'intérieur des filetages ont été déterminées pour les spécimens os/implants. Pour les lits osseux centraux sans implant la quantité osseuse dans les lésions osseuses a été déterminée. Aucune différence significative dans les valeurs de torsion à l'enlèvement n'a été trouvée entre les deux groupes. Les mesures histomorphométriques du contact os/implant et la densité osseuse à l'intérieur des filetages paroïmplantaires ne montraient aucune différence entre les deux groupes ni après deux ni après quatre semaines. Cependant des différences significatives ont été trouvées entre les échantillons à deux et quatre semaines. Dans les lits osseux centraux il n'y avait pas de différence significative de densité osseuse entre le groupe test et le contrôle. L'exposition à la nicotine durant une brève période n'avait pas d'impact significatif sur la guérison osseuse ni sur l'ostéoïntégration d'implants chez les lapines. Zusammenfassung Ziele: Den frühen Einfluss von Nikotin auf die Knochenheilung und Osseointegration zu untersuchen. Material und Methoden: 16 weibliche Kaninchen wurden in zwei Gruppe eingeteilt. Der Testgruppe wurde während 8 Wochen Nikotintartrat gegeben und die Kontrollgruppe bekam ein Placebo. Das Nikotin oder das Placebo wurde mittels einer miniosmotischen Pumpe verabreicht und man bestimmte wöchentlich die Kotininspiegel im Plasma. Bei den Tieren der Testgruppe lieferte die Pumpe 15 mg Nikotin pro Tag. Bei allen Tieren wurden 3 Stellen des Tibiaknochens bearbeitet. In das proximale und distale Knochenbett wurden nach 4 Wochen (rechte Tibia) und nach 6 Wochen (linke Tibia) Implantate eingesetzt. So wurden Gruppen mit einer Heilungszeit von 2 und 4 Wochen kreiert. Bei den distalen Implantaten wurden Ausdrehmoment-Tests (RMT) durchgeführt. Von den zentralen und proximalen Knochenbetten wurden Schliffpräparate angefertigt. Bei den Präparaten mit Implantaten und Knochen bestimmte man den Anteil an mineralisiertem Knochen in Kontakt mit dem Implantat (BIC) und die Knochendichte innerhalb der Gewindegänge (BD-i). Bei den zentralen Knochenbetten ohne Implantate bestimmte man die Knochendichte (BD-c) innerhalb der Knochendefekte. Resutate: Bei den RMT-Werten konnten zwischen der Test- und Kontrollgruppe keine signifikanten Unterschiede gefunden werden. Die histomorphometrischen Messungen des BIC und der periimplantären BD-i zeigten nach 2 oder 4 Wochen keine signifikanten Unterschiede zwischen der Test- und Kontrollgruppe. Jedoch konnten signifikante Unterschiede zwischen den Präparaten nach 2 und 4 Wochen gefunden werden. Bei den zentralen Knochenbetten bestand kein signifikanter Unterschied im BD-c zwischen der Test- und Kontrollgruppe. Schlussfolgerung: Die Verabreichung von Nikotin über einen kurzen Zeitraum hatte keinen signifikanten Einfluss auf die Knochenheilung und Osseointegration bei Kaninchen. Resumen Objetivos: Examinar los efectos a corto plazo de la nicotina en la cicatrización ósea y la osteointegración. Material y Métodos: Se dividieron 16 conejos hembras en dos grupos. El grupo de prueba fue expuesto a tartrato de nicotina durante 8 semanas y el grupo de control fue expuesto a un placebo. La nicotina o el placebo se administraron por medio de una bomba miniosmótica y se midieron e los niveles de nicotina semanalmente. La bomba suministró 15 mg de nicotina/día a los animales del grupo de prueba. Todos los conejos se sometieron a 3 preparaciones tibiales. En los lechos óseos proximales y distales, se colocaron implantes tras 4 semanas (tibia derecha) y 6 semanas (tibia izquierda). Creándose por lo tanto, dos grupos de cicatrización de 2 y 4 semanas. Se llevó a cabo un test de torque de remoción (RMT) en los implantes distales. Se realizaron cortes histológicos de los lechos óseos proximales y centrales. Se determinó la fracción de hueso mineralizado en contacto con el implante (BIC) y la densidad ósea entre las roscas (BD-i) para los especímenes de hueso-implante. Se determinó la densidad ósea (BD-c) en los defectos para los lechos óseos centrales sin implantes. Resultados: No se encontraron diferencias significativas en los valores RMT entre los grupos de prueba y de control. Las mediciones histomorfométricas del BIC y del BD-i periimplantario no mostraron diferencias significativas entre los grupos de prueba y de control tras 2 o tras 4 semanas. De todos modos se encontraron diferencias significativas entre las muestras de 2 y 4 semanas. En los lechos óseos centrales no hubo diferencias significativas en BD-c entre los grupos de prueba y de control. Conclusión: La exposición a la nicotina durante un corto periodo de tiempo no tuvo un impacto significativo en la cicatrización ósea o en la osteointegración implantaria en los conejos. [source] | ||||||||||