Rat age-related benign prostate hyperplasia is concomitant with an increase in the secretion of low ramified α-glycosydic polysaccharides.

This work analysed the expression of prostate polysaccharides in rats with age-related benign prostatic hyperplasia (BPH) for a better understanding of the possible relationship between prostate polysaccharides secretion and BPH onset. For this, prostatic glands from 1 month-old, 3 months-old, 6 months-old and 12 months-old Sprague-Dawley rats were processed in order to identify their overall polysaccharide content. Additionally, serum testosterone was also determined. One-month old rats showed significantly (P < 0.05) lower testosterone levels (0.77 ng/mL±0.12 ng/mL) compared with the other groups, which showed no significant difference among them. PAS staining showed positive polysaccharides markings in both the prostatic lumen and inside of luminal prostatic cells in all groups. Semiquantitative analysis of intraluminal PAS showed that one month-old rats had significantly (P < 0.005) lower PAS intensity when compared with all other groups (100.0 ± 0.5, arbitrary units vs. 107.3 ± 0.6, arbitrary units in 3 months-old ones), whereas 12 months-old ones showed significantly (P < 0.005) higher values when compared with all other groups (133.6 ± 3.5, arbitrary units in 12 months-old rats vs. 108.6 ± 1.4, arbitrary units in 6 months-old ones). The PAS + content practically disappeared when tissues were pre-incubated with either α-amylase or amyloglucosidase, regardless of a previous incubation with proteinase K. Incubation of prostate extracts from 12 months-old rats for 2 h with α-amylase yielded a significantly higher amount of free glucose (1.47 nmol/mg protein±0.23 nmol/mg protein vs. 0.32 nmol/mg protein±0.01 nmol/mg protein in untreated extracts). Similar results were obtained when extracts were pre-incubated with amyloglucosidase. Contrarily, pre-incubation with N-glycosidase induced a significantly (P < 0.05), much lower increase of free glucose. Pre-treatment with proteinase K did not significantly modify these results, which indicate that BPH is related to an increase in the secretion of low ramified ductal α-glycosydic polysaccharides that were not protected against lysis by any type of protein protective core. These changes seem to not be related with concomitant variations in serum testosterone levels.

The onset of age-related benign prostatic hyperplasia is concomitant with increased serum and prostatic expression of VEGF in rats: Potential role of VEGF as a marker for early prostatic alterations.

The onset of age-related benign prostate hyperplasia (BPH) is linked with changes in the expression of specific prostatic chemokines. The aim of this work was to characterize those most relevant changes through the simultaneous analysis of 34 chemokines in both prostatic tissue and serum in rats at different ages with the aim to identify clinically workable parameters for the detection of early prostatic alterations. The study included 28 healthy Sprague-Dawley male rats that were distributed in four groups, 1 month-old (prepuberal; n = 7), 3 months-old (young; n = 7), 6 months-old (mature; n = 7) and 12 months-old (elder; n = 7). Chemokines were analyzed through a commercial mini-array system specially designed for rat tissues. Serum testosterone levels and prostatic histological status were also evaluated. Histological lesions indicative of BPH were detected in three mature rats and in all elder ones. Mini-arrays from prostatic tissue showed that young animals had an overall decreased expression of most of the analyzed chemokines when compared with prepuberal rats, with the exception of agrin, which showed a significant (P < 0.05) increase (100.0 ± 1.3, arbitrary units in prepuberal rats vs.148.2 ± 4.1, arbitrary units in young ones). Older animals showed further specific changes in 4 out 34 analyzed chemokines, namely agrin, platelet-derived growth factor (PDGF), tissue inhibitor of metalloproteinase-1 (TIMP-1) and vascular endothelial growth factor (VEGF). Additionally, elder rats showed the lowest intensity levels of agrin combined with the highest ones for PDGF, TIMP1 and VEGF when compared with all other groups. Finally, a significant increase of serum VEGF was detected in elder, BPH-affected rats when compared with young ones. Results indicated that the onset of both rat puberty and BPH would be related with specific changes in the prostatic expression of chemokines such as VEGF. Otherwise, the observed changes in serum VEGF levels could suggest the future possible utilization of serum VEGF levels to detect early pathological prostatic processes.

Effects of intrauterine devices on proteins in the uterine lavage fluid of mares.

Intrauterine devices block luteolysis in cyclic mares, but the underlying mechanism is unknown. To clarify the mechanisms, the protein profile of the endometrial secretome was analyzed using two-dimensional difference gel electrophoresis (2D-DIGE). Twenty-seven mares were classified according to whether they were inseminated (AI) or had an intrauterine device (IUD), a water-filled plastic sphere, inserted into the uterus on Day 3 after ovulation. Uterine lavage fluids were collected on Day 15 from pregnant inseminated mares (AI-P; n = 8), non-pregnant inseminated mares (AI-N; n = 4), and mares with IUD (n = 15). The IUD group was further divided into prolonged (IUD-P; n = 7) and normal luteal phase (IUD-N; n = 8) groups on the basis of ultrasound examinations, serum levels of progesterone and PGFM on Days 14 and 15, and COX-2 results on Day 15. Four mares from each group were selected for the 2D-DIGE analyses. Ten proteins had significantly different abundance among the groups, nine of the proteins were identified. Malate dehydrogenase 1, increased sodium tolerance 1, aldehyde dehydrogenase 1A1, prostaglandin reductase 1, albumin and hemoglobin were highest in pregnant mares; T-complex protein 1 was highest in non-pregnant mares; and annexin A1 and 6-phosphogluconolactonase were highest in IUD mares. The results suggest that the mechanism behind the intrauterine devices is likely related to inflammation.

Relationship of aquaporins 3 (AQP3), 7 (AQP7), and 11 (AQP11) with boar sperm resilience to withstand freeze-thawing procedures.

Cryopreservation is the most suitable method to preserve boar spermatozoa over long-term storage. However, freeze-thawing protocols inflict extensive damage to sperm cells, reducing their viability and compromising their fertilizing ability. In addition, high individual variability is known to exist between boar ejaculates, which may be classified as of good (GFE) or poor (PFE) freezability. While conventional spermiogram parameters fail to predict sperm cryotolerance in fresh spermatozoa, high levels of certain proteins, also known as freezability markers, have been found to be related to the sperm resilience to withstand freeze-thawing procedures. In this context, the hypothesis of this study was that aquaporins AQP3, AQP7, and AQP11 could be linked to boar sperm cryotolerance. Twenty-nine ejaculates were evaluated and subsequently classified as GFE or PFE based upon their sperm viability and motility at post-thawing. Fourteen ejaculates resulted to be GFE, whereas the other fifteen were found to be PFE. Relative abundances of AQP3, AQP7, and AQP11 and their localization patterns were evaluated in all fresh and frozen-thawed ejaculates through immunoblotting and immunocytochemistry. Prior to cryopreservation, relative amounts of AQP3 and AQP7 were found to be significantly (p < 0.05) higher in GFE than in PFE. In contrast, no significant differences (p > 0.05) between freezability groups were found for AQP11, despite GFE tending to present higher levels of this protein. The localization of AQP7, but not that of AQP3 or AQP11, was observed to be affected by cryopreservation procedures. In conclusion, these results suggest that AQP3 and AQP7 are related to boar sperm cryotolerance and may be used as freezability markers.

Effects of Intrauterine Devices in Mares: A Histomorphological and Immunohistochemical Evaluation of the Endometrium.

Oestrous suppression by intrauterine devices (IUDs) is caused by prolongation of luteal function, but the biological mechanism is unknown. The aim of the study was to investigate mechanisms which could explain the action of IUDs. Thirty mares were age-matched and either inseminated (AI, n = 15) or fitted with an IUD (IUD, n = 15) and subsequently divided into four groups: AI-P, pregnant (n = 8); AI-N, non-pregnant (n = 7); IUD-P, prolonged luteal phase (n = 7); and IUD-N, normal luteal phase (n = 8). The median ages were 5.5 and 7 years in AI-P and IUD-P groups and 14 and 11 years in AI-N and IUD-N groups, respectively. On Day 15 after ovulation, an endometrial biopsy was obtained to study histomorphological and immunohistochemical expression patterns of uterine proteins (uteroferrin, UF; uterocalin, UC; uteroglobin, UG), oestrogen and progesterone receptors (ER, PR), proliferation marker Ki-67 and content of inflammatory cells. Expression of UF was higher in IUD mares; the difference between pregnant and IUD-P mares was significant. Mares exhibiting a prolonged luteal phase (AI-P, IUD-P) showed only mild angiosclerosis and lower expression of both ER and PR than mares with a normal luteal phase (AI-N, IUD-N). No significant differences were detected in the numbers of inflammatory cells, with the exception of macrophages, which were more numerous in AI-P than AI-N mares. Although inflammatory cells were not detected in IUD mares, increased UF levels may indicate chronic inflammation. Young age and normality of the endometrial blood vessels may improve the efficacy of IUDs.

Doppler evaluation of the effects of propofol, etomidate and alphaxalone on fetoplacental circulation hemodynamics in the pregnant ewe.

INTRODUCTION: Umbilical artery (UA) hemodynamics reflect blood flow and vascular resistance in the placental circulation. We examined non-invasively the hemodynamic effects of propofol, etomidate, and alphaxalone on the placental circulation of a sheep model by means of UA Doppler ultrasonography. METHODS: Eleven sheep fetuses were examined at 90-109 days of gestation. UA Doppler ultrasound was performed before and after administration of a single intravenous bolus of propofol, etomidate, or alphaxalone. UA Doppler velocities (peak systolic velocity, end diastolic velocity, and mean velocity), vascular indices (pulsatility index, resistance index, and S/D ratio), blood flow, and fetal heart rate were recorded during the experimental period and UA Doppler waveforms were characterized. RESULTS: A laminar, parabolic, low resistance flow was observed in the UA of the sheep fetuses. No statistically significant changes were observed in the UA Doppler waveforms or in the UA Doppler hemodynamics after anesthesia induction. DISCUSSION: Changes in placental vascular resistance may alter the corresponding UA Doppler waveforms. When resistance in the fetal placenta increases, blood flow in the UA becomes more pulsatile. In the present study, umbilical arteries showed a parabolic flow with low resistance in all cases, as it occurs in normal human pregnancy. The administration of these anesthetics did not cause abnormalities in the normal UA Doppler pattern, inducing no changes in the resistance of the placenta in any case. CONCLUSION: These results suggest that intravenous anesthetic induction with propofol, etomidate, or alphaxalone does not cause significant detrimental effects on the placental circulation of the pregnant ewe.

Effects of ovariohysterectomy on intra-abdominal pressure and abdominal perfusion pressure in cats.

Intra-abdominal pressure (IAP) and abdominal perfusion pressure (APP) have shown clinical relevance in monitoring critically ill human beings submitted to abdominal surgery. Only a few studies have been performed in veterinary medicine. The aim of this study was to assess how pregnancy and abdominal surgery may affect IAP and APP in healthy cats. For this purpose, pregnant (n=10) and non-pregnant (n=11) queens undergoing elective spaying, and tomcats (n=20, used as controls) presented for neutering by scrotal orchidectomy were included in the study. IAP, mean arterial blood pressure (MAP), APP, heart rate and rectal temperature (RT) were determined before, immediately after, and four hours after surgery. IAP increased significantly immediately after abdominal surgery in both female groups when compared with baseline (P<0.05) and male (P<0.05) values, and returned to initial perioperative readings four hours after surgery. Tomcats and pregnant females (P<0.05) showed an increase in MAP and APP immediately after surgery decreasing back to initial perioperative values four hours later. A significant decrease in RT was appreciated immediately after laparotomy in both pregnant and non-pregnant queens. IAP was affected by abdominal surgery in this study, due likely to factors, such as postoperative pain and hypothermia. Pregnancy did not seem to affect IAP in this population of cats, possibly due to subjects being in early stages of pregnancy.

Modulation of the biochemical composition of amniotic and allantoic fluids as a control mechanism of feline foetal development.

Amniotic fluid exerts a protective function and is an essential component for foetal development and maturation during pregnancy. However, little is known about the exact physiological functions of foetal fluids in this process as well as their biochemical composition in cats. In the present study, the biochemical composition of amniotic and allantoic fluids and maternal serum in pregnant queens was compared after performing an ovariohysterectomy. Fifteen queens were included in the study and distributed in four different groups, D(30), D(40), D(50) and D(60), according to their gestational age. Foetal fluids showed thoroughly greater concentrations of dissociate and total bilirubin, bile acids and gamma-glutamyl transferase than those of maternal serum, whereas albumin, total protein, alanine-transferase, creatine-kinase, amylase, lipase, triglycerides, cholesterol, HDL-cholesterol, and LDL-cholesterol were significantly lower, as compared to maternal serum. Other parameters like alkaline phosphatase, uric acid, creatinine, and electrolytes showed significant differences at specific stages of pregnancy, when compared to maternal serum. Lactate and cortisol significantly increased at the end of the pregnancy in foetal fluids, when compared with maternal serum. No significant differences between foetal fluids and maternal serum were observed for aspartate aminotransferase, lactate dehydrogenase, urea, phosphorus and glucose. According to our results, foetal fluids composition is not a result of simple filtration from maternal blood, the fetus being an active element involved in the production of the same and reflecting organ development and maturation.

Mechanisms behind intrauterine device-induced luteal persistence in mares.

Intrauterine glass balls are used to prevent oestrous signs in sports mares, but the mechanism of action is unknown. It has been suggested that the glass ball can mimic an embryo or act via an induced chronic uterine inflammation and absent or continuous low-grade prostaglandin (PG) release. The purpose of this study was to induce prolonged luteal function in mares using a small intrauterine device (IUD) and to study the mechanisms behind prolonged IUD-induced luteal function. A uterine swab and a biopsy specimen were obtained in early oestrus. A water-filled plastic ball, diameter 20mm and weight 3.6g, was inserted into the uterus 2-4 days after ovulation; the control mares underwent similar cervical manipulation without ball insertion. The mares were examined three times per week until day 23 and twice weekly thereafter until they returned to oestrus (transrectal palpation, ultrasonography and progesterone determination). The location of the IUD was recorded and ultrasound scans were video-recorded to assess the frequency of uterine contractions. When the mare returned to oestrus, a uterine swab and biopsy specimen were obtained and the bacteriological, cytological and histological (inflammation and glandular dilation) results compared with the samples obtained before the IUD insertion. The PG F(2alpha) metabolite levels were measured in the plasma of four control mares and eight IUD mares on days 11-16. The IUD induced a prolonged luteal phase in 75% of the mares (9/12; IUD-P); the mean dioestrous length was 57.0 days. The three mares that did not respond to the IUD (IUD-N) showed a mean dioestrous length of 15.7 days and the 12 control mares 16.1 days. The inflammation and glandular dilation scores were not significantly different in pre- and post-manipulation biopsy specimens. Although locational changes of the IUD were observed, they occurred over very small distances and were mostly limited within the body-bifurcation area. The IUD-N and control mares showed increased uterine contractility 11-16 days post-ovulation, whereas the IUD-P mares did not. The control mares (n=4) and IUD-N mares (n=2) showed increased PG levels from day 14 post-ovulation, while the IUD-P mares (n=6) showed basal levels only. We concluded that the IUD did not cause continuous PG release and suggest that close contact of the IUD with the endometrium may prevent the endometrial cells from releasing PGF(2alpha).