QRFP in female rats: Effects on high fat food intake and hypothalamic gene expression across the estrous cycle
23
Citation
58
Reference
10
Related Paper
Citation Trend
This study investigated the levels of mRNA of POMC, AgRP and MC4R in the arcuate nucleus and paraventricular nucleus of the hypothalamus in thirty Sprague Dawley rats fed a low fat diet or a high fat diet over the course of 12 weeks. The HF group had higher levels of POMC (p=0.013) and AgRP (p=0.001) in the ARC after 7 weeks of feeding. The HF group did have higher levels of MC4R (p=0.038) in the PVN after 12 weeks of feeding. POMC and AgRP mRNA expression in the ARC seemed to increase and decrease in a similar pattern during high fat feeding, while the varying levels of MC4R mRNA expression in the PVN seems to be inversely related to AgRP and POMC expression in the ARC. This may indicate a link in regulation or a breakdown energy balance that supports a state positive energy balance.
Cite
Citations (0)
Norepinephrine has been assayed in the hypothalamus of rats during different phases of the estrous cycle. The content of catecholamine in the anterior and middle hypothalamus was minimal at estrus, rose significantly during diestrus, and reached maximal levels during proestrus. In the posterior hypothalamus no significant changes were detected. (Endocrinology81: 1405, 1967)
Cite
Citations (86)
Real-time Q-PCR was used to analyze the relative expression levels of Frizzed 1-10 mRNAs in the mice ovaries at different estrous stages.The results showed that they had different expression patterns except Frizzed 8.Expressions of Frizzed 1 and 2 were the highest in proestrus and both were about 4 times higher than those in diestrus(P0.05).Frizzed 3 was 1.5 fold higher in proestrus and diestrus than those in the other two periods(P0.05).Frizzed 4 was found significantly higher expression in estrus,which is about 3 fold than that in diestrus(P0.05).Frizzed 5 was marked higher in diestrus than those in proestrus and estrus,being approximately 5 times higher than that in estrus(P0.05).Frizzed 7 was similar to Frizzed 5,about 4 fold higher than the level in proestrus(P0.05).Frizzed 10 expression in proestrus was about more than 3 times higher than that in estrus(P0.05),but Frizzed 6 and 9 were no significant difference during the estrous cycle(P0.05).These results suggested that Frizzeds were widely and differentially expressed in estrous ovary and Frizzed 1—4 may play a more important role in the development of follicle during the estrous cycle.
Cite
Citations (0)
To ascertain the changes of vaginal cells at different stages of estrous cycle in Duolang sheep,vaginal smear method was used in five Duolang sheep with a normal estrous cycle,and the vaginal smear samples were collected and continuously observed by microscopic examination for 20 days.The results showed that the vaginal cells were mainly composed of keratinocytes,nucleated epithelial cells,and leukocytes.Keratinocytes constituted the majority in estrus,and there were no significant differences(P0.05) among three kinds of cells with similar number in metestrus;most of the cells were leukocytes in diestrus;most of the cells were nucleated epithelium cells in proestrus.According to the changes in cell types,the estrous cycle was determined,it was found that the duration of the different stages was as follows: metestrus(4±1)d,diestrus(9±3)d,proestrus(16±3)d,and estrus(2±1)d.It is indicated that the vaginal smear method can accurately determine the different stages of estrous cycle in Duolang sheep.
Vaginal smear
Cite
Citations (0)
Beef Cattle
Cite
Citations (124)
Based on studies of vaginal smears from wild-caught Swedish wood mice, females with three types of estrous cycles were identified: females with a continuous estrus; females with an estrous cycle between 6 and 11 days in length; and females that only rarely showed signs of estrus. We tested the pregnancy rates and how stable the estrus patterns were among the females. Ninety-one percent of the females with a continuous estrus pattern became pregnant, 50% of the females showing a cyclic estrus pattern, and 60% of the females showing an infrequent estrus. However, pregnancy occurred about 2 weeks later in females with an infrequent estrus pattern. Some females changed their estrus pattern after pregnancy, indicating that estrus patterns are not fixed.
Cite
Citations (5)
Mature Angus and Angus x Hereford cows were used to determine the effects of confinement area and number of cows in estrus on estrous behavior. During each of 2 replicates, 32 nonpregnant, nonlactating cows were maintained in a drylot (60 x 100 m) or in a pasture (12 ha). Estrous cycles were synchronized with 2 injections of PGF(2alpha) 10 to 14 d apart at the initiation of the experiment. Thereafter, PGF(2alpha) was administered between d 6 and 18 of the estrous cycle so that 1, 2 to 3, 4 to 6, or > or = 7 cows were in estrus at the same time. Concentrations of progesterone were quantified in plasma at treatment to ensure cows had a normal response to PGF(2alpha). Duration of estrus and the number of mounts received during estrus were recorded by HeatWatch. If any part of estrus for a cow occurred at the same time as estrus for another cow, the cow was considered to have concurrent estrus with the other cow. Cows in the drylot had a shorter (P < 0.02; 61.8 +/- 3.1 h) interval to estrus after PGF(2alpha) compared with cows on pasture (72.8 +/- 3.3 h). The interval to estrus was longer (P < 0.07) when cows were treated with PGF(2alpha) on d 10 to 13 (76.7 +/- 3.3 h) of the estrous cycle than when treated on d 6 to 9 (62.3 +/- 4.7 h) or d 14 to 18 (62.9 +/- 3.6 h). Increasing the number of cows concurrently in estrus increased the number of mounts each cow received per estrus (P < 0.001) and the duration of estrus (P < 0.01). When only 1 cow was in estrus, she received 11.0 +/- 6.2 mounts during 11.6 +/- 1.5 h. When > or = 7 cows were in estrus at the same time, each cow received 50.4 +/- 3.2 mounts during 17.3 +/- 0.8 h. Cows in drylot were in estrus longer (P < 0.04; 16.4 +/- 0.8 h) than cows on pasture (14.2 +/- 0.7 h). Duration of the longest interval between mounts received decreased (P < 0.002) as the number of cows in estrus at one time increased (5.3 +/- 0.7 h for 1 estrous cow; 2.6 +/- 0.3 h when > or = 7 cows were in estrus). We conclude that increasing the number of beef cows in estrus at the same time will increase the number of times a cow is mounted and the duration of estrus. The increase in estrous behavior associated with more cows in estrus could increase the number of estrous cows detected with infrequent visual observation.
Cite
Citations (15)
The experiment observed the estrous cycle of twenty-five mice with two vagina smear methods .The mice whose estrous cycle were regular were cheese to handle with superovulation method. According to the different periods (estrus,post-estrus,interestrus ),these mice classified into three test groups, and then other thirteen mice that were unknown estrous cycle were contrast group. The results showed that : (1) The method 2 was better than method 1, the method 2 had little effect to the estrous cycle of the mice. (2) The superovulation results of the interestrus mice were the best of all other periods. The rates of the valuable embryos and embryos quantity were significantly better than the estrus,post-estrus and unknown estrous cycle.
Cite
Citations (0)
Cite
Citations (2)
The objectives of this study were to determine directly if mounting activity in dairy cattle varied as a function of stage of the estrous cycle and to determine if mounting by cows could be stimulated when novel estrous cows were introduced. Detector cows were normally cycling. Estrous cows were ovariectomized and injected with estradiol cyprionate and progesterone to induce standing estrous behavior. Familiar estrous cows (prior exposure to detector cows) and novel estrous cows (no prior exposure to detector cows) encountered each detector cow (n=19) in a one-on-one manner for a 10-min period. Mounting activity by detector cows was determined by observation on d 5, 10, 15, day of estrus and d 5 of the subsequent cycle (52). The first d 5 was considered an acclimation day and was deleted from the data because all estrous cows (n=4) used were novel. These novel estrous cows then became familiar estrous cows on the subsequent days (10, 15, estrus, 52). On these days, familiar (n=4) and novel (n=2) estrous cows encountered individually each detector cow in a prearranged sequence. Stage of the estrous cycle influenced (P<.001) the frequency of mounting by detector cows. Mounting activity of detector cows was inversely related (r=−.64, P<.001) to concentrations of plasma progesterone. The introduction of novel estrous cows tended to stimulate (P=.07) mounting when all days were considered. In addition, the introduction of novel estrous cows stimulated (P<.001) mounting on d 15 and 52- A second experiment was conducted to determine if the introduction of novel estrous cows stimulated mounting in the detector cows on the day of estrus if a longer encounter time (30 min) was used. A total of eight detector cows and eight estrous cows (four familiar and four novel) were used. When the detector cow was in standing estrus, she encountered one-on-one each of two familiar estrous cows and each of two novel estrous cows in a prearranged sequence for 30-min. The introduction of novel estrous cows stimulated (P=.001) mounting by the detector cows on the day of estrus (6.50 ± .48 vs 4.37 ± .48 mounts for N and F cows, respectively). We conclude that mounting activity is reduced during midcycle and that the introduction of novel cows stimulated mounting activity on d 15, day of estrus and on d 5 of the estrous cycle.
Cite
Citations (26)