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Physiology & Behavior Oct 2021The hormones estrogen and progesterone alter physiological functions, including the estrus cycle and relevant neurological and synaptic activity. Here, we determined the...
The hormones estrogen and progesterone alter physiological functions, including the estrus cycle and relevant neurological and synaptic activity. Here, we determined the extent to which estrus cycle stage interacts with an inflammatory stimulus, lipopolysaccharide (LPS), to alter synaptic mitochondrial respiration in female rats. LPS elevated synaptic mitochondrial respiration of rats in estrus, but not diestrus. Likewise, estrogen concentration correlated with multiple respiratory metrics in LPS treated females in estrus. These data suggest estrogen likely modulates synaptic mitochondrial respiration in a high progesterone environment.
Topics: Animals; Diestrus; Estrogens; Estrus; Female; Lipopolysaccharides; Progesterone; Rats
PubMed: 34229031
DOI: 10.1016/j.physbeh.2021.113523 -
Tierarztliche Praxis. Ausgabe K,... Jun 2019Two intact bitches aged 9 and 11 years were referred due to chronic polyuria, polydipsia, vomiting, anorexia and progressive lethargy. On clinical examination, signs...
Two intact bitches aged 9 and 11 years were referred due to chronic polyuria, polydipsia, vomiting, anorexia and progressive lethargy. On clinical examination, signs of tissue overgrowth (large paws, widened interdental space, pharyngeal stridor) were noticed. Diabetes mellitus (DM) was diagnosed in one dog (case 1) and diabetic ketoacidosis (DKA) in the other (case 2). There were increased IGF-1 values suggestive of hypersomatotropism. Progesterone values and pathological findings of the ovaries and uterus indicated diestrus. Diagnosis of diestrus-induced hypersomatotropism was made and ovariohysterectomy was performed in both dogs. Dog 1 also had multiple mammary neoplasms treated with bilateral mastectomy. Treatment resulted in diabetic remission in case 1 and improved glycaemic control in case 2. Overall, diestrus-induced hypersomatotropism is rare but should be considered in any intact diabetic bitch with acromegalic features. Ovariohysterectomy is recommended and associated with a fair to good prognosis.
Topics: Acromegaly; Animals; Diabetes Complications; Diestrus; Dog Diseases; Dogs; Female; Hysterectomy; Mastectomy
PubMed: 31212352
DOI: 10.1055/a-0886-9360 -
Journal of Dairy Science Mar 2021Our objective was to investigate the lipid content of uterus, blood plasma, and milk at early, mid, and late diestrus. Lactating cows (n = 30) had the estrous cycle and...
Our objective was to investigate the lipid content of uterus, blood plasma, and milk at early, mid, and late diestrus. Lactating cows (n = 30) had the estrous cycle and ovulation synchronized by administration of exogenous hormones. Cows were blocked by parity and assigned randomly to receive transcervical uterine flushing and biopsy on d 5 (early diestrus), 10 (mid diestrus) or 15 (late diestrus) of the estrous cycle. Flushing and endometrial biopsy were performed in the uterine horn ipsilateral to the corpus luteum. The recovered flushing was used for analyses of lipid composition by liquid chromatography-tandem mass spectrometry and the biopsy was used for investigation of lipid droplet abundance in endometrial cryosections using a neutral lipid fluorescent dye. In addition, blood and milk samples were collected from all cows on d 5, 10, and 15. All blood samples were used to measure the concentration of progesterone in plasma, and all milk samples were used to determine milk composition. Subsamples of blood plasma and milk were also used to evaluate the composition of fatty acids and oxylipins using the same methodology used for uterine flushing samples. The abundance of lipid droplets in the endometrium increased 1.9-fold from d 5 to 10, and 2-fold from d 10 to 15. Concentration of long-chain fatty acids and oxylipins in uterine flushing were, on average, 2.2 and 2.5 times greater in samples collected on d 15 compared with those collected on d 5 and 10. These differences were not observed in blood and milk, suggesting that accumulation of fatty acids and oxylipins in the uterus is regulated locally. In addition to concentration, the profile of individual fatty acids and oxylipins in uterine lumen changed substantially during diestrus. The main categories with increased abundance at late diestrus were mono- and polyunsaturated fatty acids, and oxylipins derived from arachidonic acid, dihomo-γ-linolenic acid, and docosahexaenoic acid. In conclusion, fatty acids and oxylipins accumulate in the uterine lumen during diestrus and might work as a mechanism to supply these lipids to the developing conceptus at late diestrus, when the onset of elongation occurs and substantial synthesis of biomass and cell signaling by lipid mediators are required.
Topics: Animals; Cattle; Diestrus; Endometrium; Fatty Acids; Female; Lactation; Lipid Droplets; Milk; Oxylipins; Pregnancy; Uterus
PubMed: 33455794
DOI: 10.3168/jds.2020-19196 -
Journal of Equine Veterinary Science Nov 2022The aim of this project was to test the hypothesis that progesterone concentration 5 days after ovulation did not differ between pregnant and nonpregnant Thoroughbred...
The aim of this project was to test the hypothesis that progesterone concentration 5 days after ovulation did not differ between pregnant and nonpregnant Thoroughbred mares on stud farms located in the Waikato region of New Zealand. A prospective cohort study was performed involving five stud farms in the Waikato region of New Zealand during the 2018 breeding season. A total of 275 mares were enrolled in the study. Mares were served by 34 individual stallions. Blood samples were taken from each mare 5 days after ovulation (D0) and measured for progesterone concentration. Early pregnancy was confirmed at D14 by transrectal palpation and ultrasonography of the mares reproductive tract. Progesterone concentration at Day 5 post-ovulation was higher in mares determined to pregnant at Day 14 of gestation than in mares determined to be non-pregnant at Day 14 (6.4 ± 3.0 ng/ml vs. 5.5 ± 3.3 ng/ml respectively; P = .02). A negative association between increasing mare age and pregnancy rate was found but mare age had no effect on progesterone concentration at D5. In this study we found that although higher serum progesterone concentration at Day 5 post ovulation was associated with a higher pregnancy rate at Day 14, no predictive or definitive minimum required progesterone concentration could be identified. Additional studies are required to determine if a synthetic progestogens can serve to supplant natural progesterone to increase pregnancy rate in naturally bred mares.
Topics: Pregnancy; Horses; Animals; Female; Male; Pregnancy Rate; Progesterone; Diestrus; Prospective Studies; Reproduction
PubMed: 36115550
DOI: 10.1016/j.jevs.2022.104127 -
Animal Reproduction Science Oct 2020The aim was to study number, volume, apoptosis of corpora lutea (CL), and serum P concentrations in early, middle, and late diestrus of dogs. Thirty-six bitches were...
The aim was to study number, volume, apoptosis of corpora lutea (CL), and serum P concentrations in early, middle, and late diestrus of dogs. Thirty-six bitches were ovari-hysterectomized (OVX): Early Diestrus (Group [G]1; OVX 20 days after end of estrus [DEH]); Mid-diestrus (GII; OVX between 21 and 40 days after DEH), and Late-diestrus (GIII; OVX between 41 and 60 days after DEH). Before OVX a blood sample was collected to quantify P. After OVX, the number of CL (NCL) was recorded, CL measured using both ultrasonography (US) and caliper (CAL), and the volume (mm) was calculated. Based on abundances of caspase-3, apoptotic luteal cells were detected. Bitches in early-diestrus had greater P concentrations than bitches in mid- and late-diestrus (23.52 ± 3.78 and 10.86 ± 3.88 ng/mL; P < 0.05). The NCL, cumulative USCLV, and CALCLV were similar among diestrus stages (P > 0.30). Bitches with CL (≥5) had twice the serum P concentrations as bitches with CL1-2 and CL3-4 (22.71 ± 3.70 and 10.97 ± 4.06 ng/mL; P < 0.05). There were correlations between P concentrations with USCLV, CALCLV, and NCL (r = 0.64, r = 0.67, r = 0.44; P < 0.0001). When serum P concentrations were adjusted for stages of diestrus, however, there were only correlations during early diestrus. The percentage of apoptotic cells was greater in GIII compared with GI and GII (13.75 ± 2.26 % compared with 4.5 ± 0.68 % and 4.6 ± 1.5 %, respectively; P < 0.05). As days of diestrus increased, number of apoptotic cells increased, and serum P concentrations decreased.
Topics: Animals; Apoptosis; Corpus Luteum; Diestrus; Dogs; Female; Progesterone
PubMed: 32947187
DOI: 10.1016/j.anireprosci.2020.106591 -
Journal of Applied Physiology... Mar 2023We recently showed that in male rats, orexin contributes to the hypoxic ventilatory response (HVR), with a stronger effect in the active phase. The effect of orexin on...
We recently showed that in male rats, orexin contributes to the hypoxic ventilatory response (HVR), with a stronger effect in the active phase. The effect of orexin on the HVR in females has not been investigated. As estrogen can inhibit orexin neurons, here we hypothesized that orexin neurons are activated by hypoxia and facilitate the HVR only in diestrus, when estrogen is low. We exposed female rats ( = 10) to near-isocapnic hypoxia ([Formula: see text] from 0.21 to 0.09) over ∼5 min, after vehicle and again after suvorexant (a dual OxR antagonist; 20 mg/kg ip), with ventilation measured using whole body plethysmography. Each rat was tested in proestrus or estrus (p/estrus), and again in diestrus, during both inactive and active phases. We also performed immunohistochemistry (IHC) to determine the proportion of orexin neurons activated by acute hypoxia during diestrus ( = 6) or proestrus/estrus ( = 6) in the active phase. In the inactive phase, the HVR was unaffected by OxR blockade, irrespective of estrus stage. In the active phase, the effect of OxR blockade depended on stage: the slope of the HVR was significantly reduced by OxR blockade only during diestrus. IHC revealed that hypoxia activated more orexin neurons during diestrus compared with p/estrus. We conclude that in females, orexin neurons are activated by hypoxia and contribute to the HVR only in diestrus when estrogen levels are low. Stage of the estrus cycle should be considered when examining the physiological function of orexin neurons in females. We previously showed that orexin facilitates the hypoxic ventilatory response (HVR) of adult male rats during the active phase. Others have shown that estrogen inhibits orexin neurons. Here we show that orexin neurons are activated by hypoxia and facilitate the HVR of adult female rats during the active phase, but only in diestrus. These data suggest that orexin neurons facilitate the HVR in females when they are free from the inhibitory effects of estrogen.
Topics: Animals; Female; Rats; Diestrus; Estrogens; Estrus; Hypoxia; Orexins; Pulmonary Ventilation
PubMed: 36656978
DOI: 10.1152/japplphysiol.00661.2022 -
Theriogenology Jan 2022This study aimed to compare the activity of selected glycosidases (β-galactosidase, α-l-fucosidase, β-N-acetyl-hexosaminidase, and sialidase) in homogenates of...
Activity of the glycosidases β-galactosidase, α-l-fucosidase, β-N-acetyl-hexosaminidase, and sialidase in uterine tissues from female dogs in diestrus with and without pyometra.
This study aimed to compare the activity of selected glycosidases (β-galactosidase, α-l-fucosidase, β-N-acetyl-hexosaminidase, and sialidase) in homogenates of uterine tissues obtained from female dogs with and without pyometra. In addition, it examined the availability of substrates for these glycosidases in the homogenates. The study was carried out on female dogs undergoing ovariohysterectomy for pyometra (n = 10) and clinically healthy dogs (n = 10) undergoing elective spaying. The activity of β-galactosidase, α-l-fucosidase, and β-N-acetyl-hexosaminidase was analyzed using a spectrofluorometer and that of sialidase using a colorimetric method. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis with Alcian Blue (AB) and Periodic Acid-Schiff (PAS) staining was performed to determine the presence of substrates for these glycosidases in the homogenates of uterine tissues. The results revealed that the activity of all the examined glycosidases was significantly higher (P < 0.05) in the uterine tissues isolated from dogs with pyometra in comparison to healthy dogs. The electrophoretic patterns of the selected samples showed several proteins, which contained different sugar moieties stained by AB and PAS and the profiles differed significantly between the pyometra group and the healthy group. Densitometric analysis of AB staining showed patterns between 233 and 148, 86 and 55, and 43 and 20 kDa, which differed markedly in sugar content between the examined groups of animals. Similarly, PAS staining analysis revealed patterns of different molecular weights, between 233 and 117 and between 55 and 32 kDa, which also differed in sugar content. These findings suggest that canine pyometra is accompanied by the increase in the activity of selected glycosidases in the uterus. This could potentially modify the glycan structures of uterine glycoproteins and in result their biological functions. Further studies are needed to elucidate the potential role of the increased activity of glycosidases in the pathogenesis of this disease.
Topics: Animals; Diestrus; Dog Diseases; Dogs; Female; Glycoproteins; Neuraminidase; Pyometra; alpha-L-Fucosidase; beta-Galactosidase; beta-N-Acetylhexosaminidases
PubMed: 34700070
DOI: 10.1016/j.theriogenology.2021.10.020 -
Journal of Psychopharmacology (Oxford,... Dec 2021Acute hypoxia, which is panicogenic in humans, also evokes panic-like behavior in male rats. Panic disorder is more common in women and susceptibility increases during...
Enhanced responsiveness to hypoxic panicogenic challenge in female rats in late diestrus is suppressed by short-term, low-dose fluoxetine: Involvement of the dorsal raphe nucleus and the dorsal periaqueductal gray.
BACKGROUND
Acute hypoxia, which is panicogenic in humans, also evokes panic-like behavior in male rats. Panic disorder is more common in women and susceptibility increases during the premenstrual phase of the cycle.
AIMS
We here investigated for the first time the impact of hypoxia on the expression of panic-like escape behavior by female rats and its relationship with the estrous cycle. We also evaluated functional activation of the midbrain panic circuitry in response to this panicogenic stimulus and whether short-term, low-dose fluoxetine treatment inhibits the hyper-responsiveness of females in late diestrus.
METHODS
Male and female Sprague Dawley rats were exposed to 7% O. Females in late diestrus were also tested after short-term treatment with fluoxetine (1.75 or 10 mg/kg, i.p.). Brains were harvested and processed for c-Fos and tryptophan hydroxylase immunoreactivity in the periaqueductal gray matter (PAG) and dorsal raphe nucleus (DR).
RESULTS
Acute hypoxia evoked escape in both sexes. Overall, females were more responsive than males and this is clearer in late diestrus phase. In both sexes, hypoxia induced functional activation (c-Fos expression) in non-serotonergic cells in the lateral wings of the DR and dorsomedial PAG, which was greater in late diestrus than proestrus (lowest behavioral response to hypoxia). Increased responding in late diestrus (behavioral and cellular levels) was prevented by 1.75, but not 10 mg/kg fluoxetine.
DISCUSSION
The response of female rats to acute hypoxia models panic behavior in women. Low-dose fluoxetine administered in the premenstrual phase deserves further attention for management of panic disorders in women.
Topics: Animals; Behavior, Animal; Diestrus; Disease Models, Animal; Dorsal Raphe Nucleus; Female; Fluoxetine; Hypoxia; Male; Menstrual Cycle; Panic; Panic Disorder; Periaqueductal Gray; Rats; Rats, Sprague-Dawley; Selective Serotonin Reuptake Inhibitors; Sex Characteristics
PubMed: 34872406
DOI: 10.1177/02698811211058986 -
Theriogenology Dec 2020Our objectives were to investigate potential changes in the size of steroidogenic large luteal cells (LLC) during partial luteolysis induced by a sub-dose of...
Partial luteolysis during early diestrus in cattle downregulates VEGFA expression and reduces large luteal cell and corpus luteum sizes and plasma progesterone concentration.
Our objectives were to investigate potential changes in the size of steroidogenic large luteal cells (LLC) during partial luteolysis induced by a sub-dose of cloprostenol in early diestrus and to determine transcriptional variations in genes involved in corpus luteum (CL) functions. Cows were subjected to an Ovsynch protocol, with the time of the second GnRH treatment defined as Day 0 (D0). On D6, cows were randomly allocated into three treatments: Control (2 mL saline, im; n = 10), 2XPGF (two doses of 500 μg of cloprostenol, im, 2 h apart; n = 8) or 1/6PGF (single dose of 83.3 μg of cloprostenol, im; n = 10). Before treatments and every 8 h during the 48-h experimental period, blood samples were collected and CL volumes measured. Furthermore, two CL biopsies were obtained at 24 and 40 h post-treatment. The 1/6PGF treatment caused partial luteolysis, characterized by sudden decreases in plasma progesterone (P) concentrations, luteal volume and LLC size, followed by increases (to pretreatment values) in P and luteal volume at 24 and 40 h post-treatment, respectively. However, at the end of the study, P4, luteal volume and LLC size were all significantly smaller than in Control cows. Temporally associated with these phenotypes, there was a lower mRNA abundance of VEGFA at 24 and 40 h, and ABCA1 at 24 h (P < 0.05). In conclusion, a sudden reduction in CL size during partial luteolysis induced by a sub-dose of PGF analog on day 6 of the estrous cycle was attributed to a reduction in LLC size, although these changes did not account for the entire phenomenon. In addition to its involvement in reducing CL size, decreased VEGFA mRNA abundance impaired CL development, resulting in a smaller luteal gland and lower plasma P concentrations compared to Control cows.
Topics: Animals; Cattle; Corpus Luteum; Diestrus; Dinoprost; Female; Luteal Cells; Luteolysis; Progesterone
PubMed: 32961354
DOI: 10.1016/j.theriogenology.2020.09.015 -
Reproduction in Domestic Animals =... Dec 2019In domestic dogs, oocyte maturation rates are low and the percentage of oocytes that remain in the stage of germinal vesicle (GV) regardless of culture conditions is...
In domestic dogs, oocyte maturation rates are low and the percentage of oocytes that remain in the stage of germinal vesicle (GV) regardless of culture conditions is high. The present study was conducted to characterize the proteome of canine oocyte at the germinal vesicle stage using label-free mass spectrometry. Ovaries were collected from 415 adult domestic dogs and oocytes were divided anestrus and diestrus group. Protein lysates were subjected to quantitative proteomic analysis to identify differentially expressed proteins in different status reproductive. All runs for each sample were performed on an Easy nLC1000 nano-LC chromatograph system directly connected to a quadrupole-type Orbitrap mass spectrometer. For identification of peptides and proteins, raw data of the spectra were loaded into MaxQuant software version 1.5.2.8. Proteomic data were analysed according to gene ontology and a protein-protein interaction network. 312 proteins were identified and grouped according to their biological processes, molecular functions and cellular component. Forty-six differentially expressed proteins among diestrus and control group were associated with at least one GO term in the biological process database. Several proteins involved in the cell cycle, fertilization, regulation of transcription and signalling pathways that are essential for the full development of oocytes and fertilization were expressed. This study identified proteins that were absent, and more or less expressed in different status reproductive. These differentially expressed proteins revealed a framework of molecular reorganization within a GV that renders its competency. This knowledge will enable the identification of target competence biomarkers and thus the establishment of more adequate means of cultivation to improve the M-I and II indexes in this species and also to better understand the physiology of the domestic dog, promoting the development of new reproduction biotechniques.
Topics: Anestrus; Animals; Cell Nucleus; Diestrus; Dogs; Female; In Vitro Oocyte Maturation Techniques; Nuclear Proteins; Oocytes; Proteome; Signal Transduction
PubMed: 31484219
DOI: 10.1111/rda.13560