ABSTRACT. The effects of acute restraint stress on sperm motility and reproductive endocrinology were investigated in adult rats. Sperm motility was determined by computer-assisted sperm analysis. Acute restraint stress reduced sperm motility starting after 30 min, and the sperm motility parameters, percentage of motile spermatozoa (%), straight-line velocity, curvilinear velocity, deviation of the sperm head from the mean trajectory and the maximum amplitude of lateral head displacement decreased. It also induced a significant elevation in plasma adrenocorticotropic hormone, prolactin, corticosterone and progesterone and decreased follicle-stimulating hormone, luteinizing hormone, testosterone and immunoreactive (ir-) inhibin. These results clearly demonstrated that the acute restraint stress rapidly suppressed sperm motility and increased the activity of the hypothalamus-pituitary-adrenal axis, whereas it disturbed hypothalamus-pituitary-gonadal axis activity.KEY WORDS: ACTH, corticosterone, LH, restraint stress, sperm motility.J. Vet. Med. Sci. 72(11): 1501-1506, 2010 Sperm motility is an important prerequisite determining the quality and fertilizing ability of semen. Several studies have demonstrated that there is a relationship between psychological stress and sperm concentration, motility and morphometry [9,14,28]. In humans, psychological stress patients had decreased sperm count and motility [4]. Stress due to examination tests disturbed luteinizing hormone (LH) and testosterone concentrations [17].Restraint stress has been used as a procedure to study the effects of stress on reproduction outcome in rodents. Several studies have reported reduced testis weight and viability or percentage of progressive epididymal spermatozoa and increased adrenal weight due to stress in rats [24,34]. In rats, the activation of the hypothalamus-pituitary-adrenal axis by stress depends mainly on the characteristics of the stressor, and the response of this axis to stress also depends on the time of day in which the stressor is applied [29]; immobilization stress resulted in decreases in testicular weights along with viability and progressive epididymal spermatozoa [24].To extend these observations and knowledge, adult male rats were used as an animal model to investigate whether and how acute restraint stress affects sperm motility and reproductive endocrinology in this study. Adult WistarImamichi male rats, weighing between 340 and 430 g and aged 3 months, from Imamichi Institute for Animal Reproduction, Ibaraki, Japan, were used. The rats were housed in a room with controlled illumination (14 L:10 D) and temperature (22°C-25°C) and were given free access to commercial pellets (CE-2, Japan Clea Co., Tokyo, Japan) and tap water ad libitum. All procedures were carried out in accordance with the Guide for the Care and Use of Laboratory Animals prepared by Tokyo University of Agriculture and Technology.Adult male rats were stressed by immobilization in a small plastic bag (DecapiCone, Braintree Scientific Inc., Braintree, MA,...

Forkhead box (Fox) proteins play critical roles in the regulation of differentiation, proliferation, immunity and aging of cells. Most studies on Fox proteins are limited to cultured cells and rodent. The aim of the current study is to detect by immunohistrochemistry whether FoxO1, FoxO3a and FoxO4 proteins are localized in the stomach and intestine of the pig. The results showed that FoxO4 exists in the mucosa in all parts of the stomach and intestine; FoxO3a exists mainly in the lamina propria and muscularis of some parts. However, FoxO1 is not detectable in all parts of the stomach and intestine. Collectively, the results of the present study indicate that there exists a distinct expression pattern of Fox proteins, and that FoxO4 is a primary forkhead transcriptional factor localized in the gastrointestinal tracts of the pig.

ABSTRACT. Pantothenic acid (PaA) is a water-soluble vitamin required to sustain various physiological functions in animals. The physiological roles of PaA on testicular function, in particular, testicular endocrinology and sperm mortility, were investigated in rats. Male rats at 3 weeks of age were fed a PaA-free diet or a 0.0016% PaA diet (control) for 7 weeks. Total body weight, as well as the weights of the liver, kidney, pituitary, testis, epididymis, seminal vesicle and prostate; sperm motility; and the plasma concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone and corticosterone were measured in rats at 10 weeks of age. Body weight gain decreased from 5 weeks of age in rats fed the PaA-free diet compared with the control. The relative weights of the testes were significantly higher in the PaA-deficient group compared with the control group. Several parameters of sperm motility were significantly reduced in the PaA-deficient group compared with the control group. In addition, the plasma concentrations of testosterone and corticosterone were significantly lower in the PaA-deficient group compared with the control group, whereas the plasma concentrations of FSH and LH showed no change. These results clearly demonstrate that PaA is an essential factor in testicular endocrinology and sperm motility in male rats. KEY WORDS: pantothenic acid, sperm motility, testosterone.

Purpose The effect of pantothenic acid (PaA) supplementation on adrenal secretion of corticosterone and progesterone in female rats was investigated. Methods An in-vitro primary adrenal cell culture system was used. Pregnant rats were given 0.03% PaA in their drinking water throughout pregnancy and the period of lactation. In the first experiment, after weaning, female rats continued to receive 0.03% PaA treatment until 10 weeks of age. The animals were then decapitated and adrenal cells were cultured in the absence or presence of rat adrenocorticotropic hormone (ACTH) for 4 h. In the second experiment, adrenal cells from lactating rats on day 5 of lactation were cultured in the absence or presence of rat ACTH for 4 h. Results The effect of ACTH at 10-10 M on corticosterone and progesterone release was greater for PaA-treated cyclic rats than for control cyclic rats. The effect of ACTH at 10 -10 M on corticosterone release was greater for PaAtreated lactating rats than for control lactating rats. Circulating ACTH and corticosterone levels in PaA-treated and control cyclic and lactating rats were no different. Conclusions These results indicate that PaA supplementation induced hyperresponsiveness to ACTH stimulation in cyclic and lactating female rats. These results clearly demonstrated that PaA is an essential factor in adrenal steroidogenesis of female rats.

-Inactivation of the cyclic nucleotide signal in granulosa cells depends on a complex array of cyclic nucleotide phosphodiesterases (PDE). In order to examine the role of PDE in cyclic AMP (cAMP) signaling in granulosa cells, the present study examined the expression of PDE4D proteins and regulation of cAMP-PDE activities in cultured rat granulosa cells. The results of immunoblot analyses showed that two predominant PDE4D subtypes of approximately 80 and 70 kDa appeared when immature rat granulosa cells were treated with FSH. However, these two new subtypes presumed to be PDE4D proteins were not influenced by treatments of DETA/NO, cGMP and PKB inhibitor, LY294002. Immature rat granulosa cells treated with medium alone displayed low cAMP-PDE activity throughout 48 h of culture while those treated with FSH (2 ng·mL -1 ) showed a marked increase in cAMP-PDE activity between 6 and 12 h of culture, followed by a decline. The findings from the present study indicate that the increased cAMP-PDE activity by FSH is mainly related to the changes of PDE4D protein levels. However, the inhibitory effects of NO on cAMP accumulation in rat granulosa cells are not via the increased cAMP-PDE activity.phosphodiesterase / cyclic AMP / granulosa cell / nitric oxide / rat

No abstract