Estrous-cycle-dependent Variation in Orthodontic Tooth Movement

2002 ◽  
Vol 81 (6) ◽  
pp. 406-410 ◽  
Author(s):  
N. Haruyama ◽  
K. Igarashi ◽  
S. Saeki ◽  
M. Otsuka-Isoya ◽  
H. Shinoda ◽  
...  
Keyword(s):  
Estrous Cycle ◽  
Wistar Rats ◽  
Tooth Movement ◽  
Orthodontic Tooth Movement ◽  
Serum Estradiol ◽  
Serum Trap ◽  
Female Wistar Rats ◽  
Cycle Dependent ◽  
Cyclic Changes ◽  
Estradiol Levels

Sex hormones, including estradiol, play important physiological roles in bone metabolism. The purpose of this study was to investigate whether there is estrous-cycle-dependent variation in orthodontic tooth movement, and, if so, to determine the mechanism. Ten-week-old female Wistar rats were used. They received repeated orthodontic force during specific phases in the estrous cycle. Tooth movement in animals that received force principally in estrus was about 33% greater than that in animals that received such force principally in pro-estrus (p < 0.05). Serum estradiol levels also varied according to the estrous cycle, with a peak during pro-estrus and a nadir during estrus, and were inversely related to tooth movement. Furthermore, there were negative correlations between estradiol and both serum TRAP activity and pyridinoline (r = -0.42, p < 0.05; r = -0.59, p < 0.001). These results suggest that cyclic changes in the estradiol level may be associated with the estrous-cycle-dependent variation in tooth movement through its effects on bone resorption.

scholarly journals The fertility assessment of normal cyclic Wistar rats following the administration of methanolic extract of Portulaca oleracea: an experimental study

2021 ◽  
Vol 26 (1) ◽  
Author(s):  
Izuchukwu Azuka Okafor ◽  
Uchenna Somtochukwu Nnamah ◽  
Jude Nnaka
Keyword(s):  
Estrous Cycle ◽  
Adult Female ◽  
Wistar Rats ◽  
Major Effect ◽  
Reproductive Hormones ◽  
Portulaca Oleracea ◽  
High Dose ◽  
Methanolic Extracts ◽  
Cycle Arrest ◽  
Female Wistar Rats

Abstract Background Purslane is a widely distributed shrub used for the treatment of different ailments. The increasing reproductive complications associated with herbal treatments have led to the need to critically evaluate the safety and/or reproductive potentials of commonly used plant extracts. This study investigated the reproductive effect of methanolic extracts of Portulaca oleracea (MEPO) in adult female Wistar rats. Results Group C showed a significant decrease both in relative ovarian weight (p = 0.000), and relative uterine weight (p = 0.037), when compared with the control. There were no significant (p ˃ 0.05) changes in the levels of follicle-stimulating hormone, luteinizing hormone, progesterone, and estradiol. When compared to the control, groups B and C showed abnormal estrous cycle and cycle arrest especially at the metestrus phase with mild congestion of a few blood vessels in the ovary and uterus. Conclusions MEPO may possess some anti-fertility effect, as it disrupts the estrous cycle of adult female Wistar rats; although it has no major effect on the reproductive hormones, uterus, and ovarian histology of adult female Wistar rats. However, high dose consumption should be taken with precaution.

scholarly journals Functional requirement of AgRP and NPY neurons in ovarian cycle-dependent regulation of food intake

2009 ◽  
Vol 106 (37) ◽  
pp. 15932-15937 ◽  
Author(s):  
Louise E. Olofsson ◽  
Andrew A. Pierce ◽  
Allison W. Xu
Keyword(s):  
Food Intake ◽  
Estrous Cycle ◽  
Estrogen Receptor Alpha ◽  
Ovarian Cycle ◽  
Central Administration ◽  
Related Protein ◽  
17Β Estradiol ◽  
Cycle Dependent ◽  
Cyclic Changes ◽  
Agouti Related Protein

In female mammals including rodents and humans, feeding decreases during the periovulatory period of the ovarian cycle, which coincides with a surge in circulating estrogen levels. Ovariectomy increases food intake, which can be normalized by estrogen treatment at a dose and frequency mimicking those during the estrous cycle. Furthermore, administration of estrogen to rodents potently inhibits food intake. Despite these well-known effects of estrogen, neuronal subtypes that mediate estrogen's anorexigenic effects have not been identified. In this study, we show that changes in hypothalamic expression of agouti-related protein (Agrp) and neuropeptide Y (Npy) coincide with the cyclic changes in feeding across the estrous cycle. These cyclic changes in feeding are abolished in mice with degenerated AgRP neurons even though these mice cycle normally. Central administration of 17β-estradiol (E2) decreases food intake in controls but not in mice lacking the AgRP neurons. Furthermore, E2 treatment suppresses fasting-induced c-Fos activation in AgRP and NPY neurons and blunts the refeeding response. Surprisingly, although estrogen receptor alpha (ERα) is the key mediator of estrogen's anorexigenic effects, we find that expression of ERα is completely excluded from AgRP and NPY neurons in the mouse hypothalamus, suggesting that estrogen may regulate these neurons indirectly via presynaptic neurons that express ERα. This study indicates that neurons coexpressing AgRP and NPY are functionally required for the cyclic changes in feeding across estrous cycle and that AgRP and NPY neurons are essential mediators of estrogen's anorexigenic function.

scholarly journals Effect of Penicillin on Reproductive Function in Female Wistar Rats

2021 ◽  
Vol 71 (2) ◽  
Author(s):  
Oyedeji K.O ◽  
Momoh R.O ◽  
Oderinde Gbenga
Keyword(s):  
Estrous Cycle ◽  
Wistar Rats ◽  
Reproductive Function ◽  
Daily Basis ◽  
Female Rats ◽  
Histopathological Study ◽  
Fertility Effect ◽  
Female Wistar Rats ◽  
Student’S T ◽  
Histopathological Studies

This study was designed to investigate the effect of penicillin on reproductive function in female Wistar rats. Fifteen female rats (120 – 160 g) were used for the estrous cycle and histopathological studies. Penicillin (17.14 mg/kg) was administered orally on daily basis for 21 and 50 days respectively for the estrous cycle and histological studies. Estrous cycle was carried out using the technique of Marcondes et al., histologies of the ovaries and uteri were also carried out. Data were analysed using descriptive statistics and student’s t-test at p=0.05. Treatment of rats for 21 days with penicillin (17.14 mg/kg) produced significant (p<0.05) increments in the estrous and metestrous phases as well as a significant (p<0.05) reduction in the proestrous phase of the estrous cycle relative to their respective controls. The histopathological study presented with a moderate endometrial congestion. It can therefore be concluded that penicillin probably has a pro-fertility effect with a moderate deleterious effect on the uteri at histological level in female Wistar rats.

Effect of serum estradiol and leptin levels on thyroid function, food intake and body weight gain in female Wistar rats

Steroids ◽  
2010 ◽  
Vol 75 (10) ◽  
pp. 638-642 ◽  
Author(s):  
Thiago U. Pantaleão ◽  
Felippe Mousovich ◽  
Doris Rosenthal ◽  
Álvaro S. Padrón ◽  
Denise P. Carvalho ◽  
...  
Keyword(s):  
Body Weight ◽  
Weight Gain ◽  
Food Intake ◽  
Thyroid Function ◽  
Wistar Rats ◽  
Body Weight Gain ◽  
Serum Estradiol ◽  
Female Wistar Rats

scholarly journals Gossypol Promotes Degeneration of Ovarian Follicles in Rats

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Ivana Cristina Nunes Gadelha ◽  
Michelly Fernandes de Macedo ◽  
Sílvia Catarina Salgado Oloris ◽  
Marilia Martins Melo ◽  
Benito Soto-Blanco
Keyword(s):  
Estrous Cycle ◽  
Wistar Rats ◽  
Serum Levels ◽  
Ovarian Follicles ◽  
The Other ◽  
Control Group ◽  
Stages Of Development ◽  
Hormone Levels ◽  
Stage Of Development ◽  
Female Wistar Rats

The present study aimed to determine if gossypol interferes with ovarian follicles in rats. Twenty-four female Wistar rats were assigned to two equal groups: one control group and the other dosed with gossypol (25 mg/kg/day, subcutaneously) for 15 days. Ovarian follicles were histologically classified according to the stage of development and as normal or atretic. Gossypol treatment reduced the length of estrous with an increase in the duration of the diestrus phase. This compound was responsible for reduced serum levels of T4 and progesterone. Treatment with gossypol was responsible for a significant reduction in the number of normal ovarian follicles and a significant increase in the number of atretic follicles, both in all stages of development. Thus, treatment of rats with gossypol was responsible for reduction in the number of viable follicles and changes in hormone levels that resulted in interference of the estrous cycle.

scholarly journals Effect of vitamin E supplementation on orthodontic tooth movement in Wistar rats: a prelimary study

F1000Research ◽  
2020 ◽  
Vol 9 ◽  
pp. 1093
Author(s):  
Erliera Sufarnap ◽  
Darmayanti Siregar ◽  
Yumi Lindawati
Keyword(s):  
Vitamin E ◽  
Wistar Rats ◽  
Tooth Movement ◽  
Orthodontic Tooth Movement ◽  
Control Groups ◽  
Osteoblast Cells ◽  
Time Intervals ◽  
Orthodontic Force ◽  
Group 2 ◽  
Group 1

Background: Tooth movement induced by the application of orthodontic force was initiated by inflammatory process. Studies have shown that vitamin E has an anti-inflammatory and antioxidant properties which perhaps could inhibit the tooth to move. This study aimed to evaluate the effect of vitamin E supplementation on orthodontic tooth movement in Wistar rats. Methods: Wistar rats (n=56) were divided into two groups. Group 1 served as the control groups, while group 2 was given vitamin E for 14 days before application of orthodontic force. Each group was divided into four subgroups (n=7), corresponding to the number of days orthodontic force lasted, i.e. 0, 1, 3, 7 days. At each of these four time points, distance measurements and quantity of osteoblasts-osteoclasts were measured in each rat. Results: Tooth movement distance was increased for group 2 than group 1 for all time intervals, but this difference was only statistically different on day 3 (p=0.001). For both groups, tooth movement was significantly different between each time interval in each group (p=0.041). The mean number of osteoblast cells was increased for group 2 compared to group 1 for all time intervals (p<0.05), but was not significant different between time intervals (p=0.897). The number of osteoclasts was not significantly different between groups, but it was statistically different between time intervals (p=0.004). Conclusion: The outcome of this study demonstrated that group 2  resulted a better tooth movement compared to group 1 on day 3, based on the distance measurement. The osteoclast cell numbers were the same within control groups, whilst  the number of osteoblast cells in group 2 was significantly higher than those in group 1.

Changes in the Serum Levels of Estradiol and Changes in Expression of Estrogen Receptor Alpha in the Bone Tissue of Ovariectomized Wistar Rats

2022 ◽  
Vol 6 (1) ◽  
pp. 01-05
Author(s):  
Armine V. Grigoryan ◽  
Alexander B. Blazhev ◽  
Tatyana M. Betova ◽  
Aneliya A. Dimitrova
Keyword(s):  
Estrogen Receptor ◽  
Bone Tissue ◽  
Wistar Rats ◽  
Receptor Expression ◽  
Reproductive Age ◽  
Ovariectomized Rats ◽  
Aromatase Activity ◽  
Estrogen Receptor Expression ◽  
Serum Estradiol ◽  
Estradiol Levels

Estradiol is an estrogen steroid hormone and is produced basically within the follicles of the ovaries. The decrease in serum estrogens concentration at menopause disrupts the metabolic balance, changes the lipid profile leading to visceral obesity, which caused an increase in serum estradiol levels, through aromatase activity. Estrogen deficiency also is a reason for the development of osteoporosis.We investigated the serum estradiol levels and changes in bone alpha estrogen receptor expression in ovariectomized rats. For this purpose, we used 20 female Wistar rats at reproductive age - 2 months divided into 2 groups: group 1 (G1)-10 animals were ovariectomized and group 2 (G2)-10 of which were sham-operated. All animals of G1 showed weight gain compared to group G2. The results showed that the values of serum 17β-estradiol in rats of G1 statistically increased compared to G2 (p <0.05). Immunohistochemical analysis revealed no difference in estrogen receptor expression between the both groups. Histomorphological analysis of femur from G1 showed the presence of pronounced osteoporosis. Ovariectomy led to the development of obesity, which caused an increase in serum estradiol levels, through aromatase activity, but this process did not prevent bone tissue from developing osteoporosis.

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