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Effect of forced swimming stress on count, motility and fertilization capacity of the sperm in adult rats  [cached]
Saki Ghasem,Rahim Fakher,Alizadeh Karim
Journal of Human Reproductive Sciences , 2009,
Abstract: Aims: The purpose of this study was to determine whether 50 days of forced swimming stress applied to adult male rats affects count, motility and fertilization capacity of sperm. Settings and Design: It is a prospective study designed in vitro. Materials and Methods: A total 30 adult male wistar rats were used in this study. All rats were divided into two equal groups (n = 15): (1) control group and (2) experimental group. Animals of the experimental group were submitted to force swimming stress for 3 min in water at 32°C daily for 50 days. Then, all male rats were sacrificed, the right epididymides were removed and sperm concentration and motility were determined. The sperm suspension was added to the ova. Fertilization capacity was assessed by counting two-cell embryos 24-26 h after completion of fertilization in vitro. Statistical Analysis Used: Data are reported as mean ± SD and percentage. The difference between the control and experimental groups was determined by the unpaired t-test. Results: The mean and standard deviation of sperm concentration in the control and experimental groups were 60.8 ± 9.3 10 6 /ml and 20.4 ± 5.3 10 6 /ml, respectively. There was a statistical difference of P < 0.05 between the two groups in terms of sperm concentration. The percentage of motility in the experimental group was significantly different ( P < 0.05). The same results were obtained in case of fertility ( P < 0.05). Stress caused by forced swimming was observed by a significant increase in the latency of the pain response in the hot-plate test ( P < 0.05). Conclusions: These results suggest that forced swimming stress in time course equal or more than spermatogenesis period, i.e. 48-50 days in the rat will be significantly effective to reduce the number and motility of sperms as well as the fertilization capacity.
Influence of Maternal Exposure to 2,3,7,8-Tetrachlorodibenzo-p-dioxin on Socioemotional Behaviors in Offspring Rats
Anh T.N. Nguyen, Muneko Nishijo, Etsuro Hori, Nui M. Nguyen, Tai T. Pham, Kohji Fukunaga, Hideaki Nakagawa, Anh H. Tran, Hisao Nishijo
Environmental Health Insights , 2012, DOI: 10.4137/EHI.S10346
Abstract: Effects of dioxins on cognitive functions were reported in previous studies conducted in humans and animals. In the present study, we investigated the influence of dioxin exposure during pregnancy on social interaction and on the activity of offspring, which are related to neurodevelopmental disturbances. In addition, we analyzed neurochemical alterations of the limbic system of rat brains to suggest one mechanism of dioxin effects on brain function. We believe that this manuscript is suitable for publication in "Environmental Health Insights" because it provides an interesting topic for a wide global audience. To clarify the relationships between maternal dioxin exposure and socioemotional functions of rat offspring, dams were given TCDD (1.0 μg/kg) on gestational day 15. Social interactions and forced swimming time were compared between TCDD-exposed and control offspring in each gender. Frequency and duration of locomotion were higher, and durations per one behavior of proximity and social contact were significantly lower in the exposed males, while only the duration of proximity was lower in the exposed females. Forced swimming time on the first day was significantly longer in the exposed males. In the limbic system of the rat brain, the levels and/or activity of CaMKIIα were decreased in males and were increased in females in the exposed offspring. These results suggest that prenatal TCDD exposure induces hyperactivity and socioemotional deficits, particularly in the male offspring due to alterations in CaMKIIα activity in the limbic system of the brain.
B-type natriuretic peptide (BNP) serum levels in rats after forced repeated swimming stress  [PDF]
Almira Had?ovic-D?uvo,Amina Valjevac,Nesina Avdagi?,Orhan Lepara
Medicinski Glasnik , 2011,
Abstract: Aim To estimate the effects of forced repeated swimming stress on BNP serum levels in rats. Methods Adult male Wistar rats weighting between 280-330 g were divided into two groups: control group (n =8) and stress group (n =8). Rats in the stress group were exposed to forced swimming stress daily, for 7 days. The rats were forced to swim in plastic tanks (90 cm wide, 120 cm deep) containing tap water (temperature ca. 25°C). The depth of water was 40 cm. Duration of each swimming session progressively increased from 10 minutes on the irst day to 40 minutes on days 6 and 7. Rats were sacriiced and blood was drawn from abdominal aorta for BNP analysis immediately after the last swimming session. B-type natriuretic serum level was determined by ELISA method using RAT BNP-32 kit (Phoenix Pharmaceutical Inc.). Results There was no statistically signiicant difference between mean BNP serum level in the stress group after the swimming period (0.81±0.14 ng/ml) as compared to the unstressed group of rats (0.8 ±0.08ng/ml). After the swimming period mean body weight slightly decreased in the stress group in comparison with values before stress period (296.3 g vs.272.8 g), but this difference was not statistically signiicant. The stress period had no inluence on food intake in the stress rat group. Conclusion The workload consisting of 40-minutes long swimming session is not suficient to provoke BNP release from myocardium in rats.
Antidepressant effect of Melissa officinalis in the forced swimming test
M Emamghoreishi,M.S Talebianpour
DARU : Journal of Pharmaceutical Sciences , 2009,
Abstract: ABSTRACT Background: In Iranian and other traditional medicines, an antidepressant effect has been indicated for Melissa officinalis (Lamiaceae). However, studies showing its antidepressant effect is lacking. Therefore, the present study was undertaken to examine whether the aqueous extract and essential oil from leaves of Melissa officinalis have an antidepressant-like activity in mice. Materials and Methods: The effect of subchronic administration of different doses of the aqueous extract (25, 75, 150, 300 mg/kg or water; n=9-10) and the essential oil (10, 25, 75, 150, 300 mg/kg or almond oil; n=9-10) on immobility, climbing, and swimming behaviors were evaluated in the forced swimming test. Fluoxetine (20mg/kg) and imipramine (15 mg/kg) were used as reference drugs. Additionally, the effect of both plant preparations on spontaneous activity was examined. Results: All doses of the aqueous extract, used in this study, produced a significant reduction in immobility along with an increase in climbing behavior which is similar to those which have been observed with imipramine. Essential oil caused a dose-dependent reduction in immobility and an increase in climbing at all studied doses, compared to control group. Only the highest dose (300mg/kg) of essential oil showed a significant increase in swimming behavior. The aqueous extract, but not the essential oil, decreased spontaneous activity in a dose dependent manner. Conclusion: The results of this study suggests that the Melissa officinalis possess an antidepressant-like activity similar to imipramine which may have a potential clinical value for treatment of depression.
Antidepressant behavioral effects of duloxetine and amitriptyline in the rat forced swimming test
Menezes, Honório Sampaio;Bueno, Bárbara Beatriz Moreira;Ciulla, Leandro;Schuh, Alexandre;Luz, Fernanda de Freitas;Alves, Rafael José Vargas;Abegg, Milena Pacheco;Cirino, Sílvia Letícia Merceo Bacchi;
Acta Cirurgica Brasileira , 2008, DOI: 10.1590/S0102-86502008000500010
Abstract: purpose: to compare the effects of the antidepressant drugs duloxetine and amitriptyline on depressive behaviors in rats. methods: fifteen male wistar rats were given systemic injections of duloxetine, amitriptyline or saline prior to a forced swimming test (fst). immobility and number of stops were measured. data were analyzed by one-way anova and kruskall-wallis. results: rats given injections of duloxetine displayed fewer stops than the amitriptyline and control group (p< 0.05). the control group and amitriptyline showed no difference (p=0.8). conclusion: duloxetine reduced depressive behaviors in the forced swimming test been more effective than amitriptyline.
A Forced Damped Oscillation Framework for Undulatory Swimming Provides New Insights into How Propulsion Arises in Active and Passive Swimming  [PDF]
Amneet Pal Singh Bhalla,Boyce E. Griffith,Neelesh A. Patankar
PLOS Computational Biology , 2013, DOI: 10.1371/journal.pcbi.1003097
Abstract: A fundamental issue in locomotion is to understand how muscle forcing produces apparently complex deformation kinematics leading to movement of animals like undulatory swimmers. The question of whether complicated muscle forcing is required to create the observed deformation kinematics is central to the understanding of how animals control movement. In this work, a forced damped oscillation framework is applied to a chain-link model for undulatory swimming to understand how forcing leads to deformation and movement. A unified understanding of swimming, caused by muscle contractions (“active” swimming) or by forces imparted by the surrounding fluid (“passive” swimming), is obtained. We show that the forcing triggers the first few deformation modes of the body, which in turn cause the translational motion. We show that relatively simple forcing patterns can trigger seemingly complex deformation kinematics that lead to movement. For given muscle activation, the forcing frequency relative to the natural frequency of the damped oscillator is important for the emergent deformation characteristics of the body. The proposed approach also leads to a qualitative understanding of optimal deformation kinematics for fast swimming. These results, based on a chain-link model of swimming, are confirmed by fully resolved computational fluid dynamics (CFD) simulations. Prior results from the literature on the optimal value of stiffness for maximum speed are explained.
Fertilization Is Not a New Beginning: The Relationship between Sperm Longevity and Offspring Performance  [PDF]
Angela J. Crean, John M. Dwyer, Dustin J. Marshall
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0049167
Abstract: Sperm are the most diverse cell type known: varying not only among- and within- species, but also among- and within-ejaculates of a single male. Recently, the causes and consequences of variability in sperm phenotypes have received much attention, but the importance of within-ejaculate variability remains largely unknown. Correlative evidence suggests that reduced within-ejaculate variation in sperm phenotype increases a male’s fertilization success in competitive conditions; but the transgenerational consequences of within-ejaculate variation in sperm phenotype remain relatively unexplored. Here we examine the relationship between sperm longevity and offspring performance in a marine invertebrate with external fertilization, Styela plicata. Offspring sired by longer-lived sperm had higher performance compared to offspring sired by freshly-extracted sperm of the same ejaculate, both in the laboratory and the field. This indicates that within-ejaculate differences in sperm longevity can influence offspring fitness – a source of variability in offspring phenotypes that has not previously been considered. Links between sperm phenotype and offspring performance may constrain responses to selection on either sperm or offspring traits, with broad ecological and evolutionary implications.
Antidepressant behavioral effects of duloxetine and fluoxetine in the rat forced swimming test
Ciulla, Leandro;Menezes, Honório Sampaio;Bueno, Bárbara Beatriz Moreira;Schuh, Alexandre;Alves, Rafael José Vargas;Abegg, Milena Pacheco;
Acta Cirurgica Brasileira , 2007, DOI: 10.1590/S0102-86502007000500005
Abstract: purpose: to compare the effects of the antidepressant drugs duloxetine and fluoxetine on depressive behaviors in rodents. methods: eighteen male wistar rats were given systemic injections of duloxetine, fluoxetine, or saline prior to a forced swimming test (fst). immobility and number of stops were measured. results: rats given injections of fluoxetine displayed significantly less immobility (p = 0.02) and fewer stops than the control group (p = 0.003). duloxetine significanlty reduced the number of stops (p = 0.003), but did not effect immobility (p = 0.48). conclusion: duloxetine and fluoxetine reduced depressive behaviors in the forced fst. however, our findings suggest that fluoxetine is more effective than duloxetine.
Fertility of male adult rats submitted to forced swimming stress
Mingoti, G.Z.;Pereira, R.N.;Monteiro, C.M.R.;
Brazilian Journal of Medical and Biological Research , 2003, DOI: 10.1590/S0100-879X2003000500016
Abstract: we investigated whether stress interferes with fertility during adulthood. male wistar rats (weighing 220 g in the beginning of the experiment) were forced to swim for 3 min in water at 32oc daily for 15 days. stress was assessed by the hot-plate test after the last stressing session. to assess fertility, control and stressed males (n = 15 per group) were mated with sexually mature normal females. males were sacrificed after copulation. stress caused by forced swimming was demonstrated by a significant increase in the latency of the pain response in the hot-plate test (14.6 ± 1.25 s for control males vs 26.0 ± 1.53 s for stressed males, p = 0.0004). no changes were observed in body weight, testicular weight, seminal vesicle weight, ventral prostate weight or gross histological features of the testes of stressed males. similarly, no changes were observed in fertility rate, measured by counting live fetuses in the uterus of normal females mated with control and stressed males; no dead or incompletely developed fetuses were observed in the uterus of either group. in contrast, there was a statistically significant decrease in spermatid production demonstrated by histometric evaluation (154.96 ± 5.41 vs 127.02 ± 3.95 spermatids per tubular section for control and stressed rats, respectively, p = 0.001). these data demonstrate that 15 days of forced swimming stress applied to adult male rats did not impair fertility, but significantly decreased spermatid production. this suggests that the effect of stress on fertility should not be assessed before at least the time required for one cycle of spermatogenesis.
Fertility of male adult rats submitted to forced swimming stress  [cached]
Mingoti G.Z.,Pereira R.N.,Monteiro C.M.R.
Brazilian Journal of Medical and Biological Research , 2003,
Abstract: We investigated whether stress interferes with fertility during adulthood. Male Wistar rats (weighing 220 g in the beginning of the experiment) were forced to swim for 3 min in water at 32oC daily for 15 days. Stress was assessed by the hot-plate test after the last stressing session. To assess fertility, control and stressed males (N = 15 per group) were mated with sexually mature normal females. Males were sacrificed after copulation. Stress caused by forced swimming was demonstrated by a significant increase in the latency of the pain response in the hot-plate test (14.6 ± 1.25 s for control males vs 26.0 ± 1.53 s for stressed males, P = 0.0004). No changes were observed in body weight, testicular weight, seminal vesicle weight, ventral prostate weight or gross histological features of the testes of stressed males. Similarly, no changes were observed in fertility rate, measured by counting live fetuses in the uterus of normal females mated with control and stressed males; no dead or incompletely developed fetuses were observed in the uterus of either group. In contrast, there was a statistically significant decrease in spermatid production demonstrated by histometric evaluation (154.96 ± 5.41 vs 127.02 ± 3.95 spermatids per tubular section for control and stressed rats, respectively, P = 0.001). These data demonstrate that 15 days of forced swimming stress applied to adult male rats did not impair fertility, but significantly decreased spermatid production. This suggests that the effect of stress on fertility should not be assessed before at least the time required for one cycle of spermatogenesis.
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