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In rabbits, the fasting-dependent reduction of LH secretion is likely mediated by leptin and estrogens via receptors in the brain. For the first time, using immunohistochemistry, the presence and regulation of receptors for leptin (Ob-R) and estradiol-17beta subtype alpha (ERalpha) were studied in the subcommissural organ (SCO) of rabbits, which were fed either ad libitum (control) or fasted for 48 h (treated) to verify whether this brain structure is a potential site of integration for metabolism and reproduction. In control rabbits, the cytoplasm of glial cells lining the SCO evidenced strong Ob-R immunoreactivity, whereas both ependymal and hypendymal cells of this glandular-like structure were negative. The Ob-R positive glial cells were identified as fibrous astrocytes using the phosphotungstic acid-hematoxylin histochemical (PTAH) and glial fibrillary acidic protein (GFAP) immunohistochemical techniques. ERalpha immunoreactive nuclei were detectable exclusively in the specialized cells forming the SCO, whereas surrounding astrocytes and neurons were negative. Compared to controls, in fasted rabbits, the staining of Ob-R immunoreaction was reduced in the cytoplasm of positive astrocytes, but greatly enhanced in plasma membranes, whereas the number of ERalpha immunoreactive SCO cells was increased (13.2+/-2.7 vs. 5.2+/-2.0, P

The aim of this work was to evaluate the hemodynamic changes in the utero-placental arterial vessels in rabbits (Orictolagus cuniculus) throughout pregnancy as well as those in the umbilical cord, aorta, and caudal vena cava of fetuses to establish their normal reference ranges for systolic peak velocity (SPV), end diastolic velocity (EDV), pulsatility index (PI), and resistance index (RI). The blood flow waveforms were monitored every 4 d in 10 rabbits from Day 10 of pregnancy onward by means of color and pulsed wave Doppler ultrasonography using a 5.5-7.5 MHz microconvex transabdominal probe. The utero-placental blood flow was characterized by steep increases and decrease in the SPV with a slow diastolic wave and relatively high EDV, whereas that of the umbilical artery was discontinuous until Day 22 of pregnancy, when a diastolic waveform was also detectable. From Day 10 to 22 of pregnancy, the fetal aorta blood flow was discontinuous, but thereafter a diastolic peak was measurable. The blood flow of the fetal caudal vena cava was characterized by a systolic peak followed by a small diastolic peak. Throughout the gestation, the SPV and the EDV of maternal and fetal vessels increased (alpha0.05), whereas the PI and the RI decreased (alpha0.05), except for the utero-placental vessels. This work confirms that the rabbit could also be a valid experimental animal model to study, by Doppler ultrasonography, functional hemodynamic changes of the fetuses and placenta vessels in both normal and pathophysiologic conditions.

Inflammation of the uterus and oviduct is associated with reduced reproductive performance in humans and domestic animals. Toll-like receptors are expressed in various immune and non-immune cells and play a crucial role in innate immunity. Toll-like receptor - 4 (TLR4) can detect lipopolysaccharide (LPS) from Gram-negative bacteria leading to the secretion of pro-inflammatory cytokines, chemokines, antimicrobial peptides and other inflammatory mediators. To investigate the effects of a local inflammation on the expression levels of TLR4 and pro-inflammatory cytokines, 12 female rabbits received an intracervical infusion with either saline solution endotoxin-free (carrier, 2 mL; n = 6) or LPS (500 μg diluted in 2 mL of saline solution; n = 6). Blood samples were performed at 0, 30, 60 and 90 min and 2,4,6 and 24 h after treatment to evaluate interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) plasma concentrations. Animals were sacrificed 24 h post-treatment. The uterus and oviducts were immediately collected. The gene expression and protein levels of TLR4 and pro-inflammatory cytokines were detected by quantitative real-time PCR (qRT-PCR) and immuno-histochemical assay, respectively. Our study showed that the intracervical administration of LPS induced local inflammation given that the animals showed no clinical signs, the histological samples revealed signs of inflammation and plasma levels of pro-inflammatory cytokines were unchanged compared to the control. LPS produced an increase in the TLR4 mRNA expression levels in the uterus with respect to the control (P

Inflammatory bowel diseases (IBD) are characterized by inflammatory conditions of the intestine. Probiotic bacteria (PB) can have beneficial effects in several gastrointestinal disorders. The objectives of this study were: (i) to provide an acute experimental IBD model induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS) in CD-1 mice, and (ii) to assess the preventive effects of Citogenex (Lactobacillus casei and Bifidobacterum lactis) supplementation on intestinal tissues and microbiota. Mice were inoculated intrarectally with saline, ethanol or different TNBS solutions. 1%TNBS induced clinical signs of colitis (P less than 0.01) and histological damage (P less than 0.01). Based on these results, mice were pre-treated with Citogenex or saline for 1, 2 or 3 weeks before 1%TNBS treatment. Probiotic pre-treatment determined a reduction of clinical signs (P less than 0.05), histological alterations of colitis (P less than 0.05) and increased beneficial bacteria (P less than 0.05). This study confirms that TNBS-induced colitis in CD-1 mice is useful for studying the mechanisms involved in IBD pathogenesis, and pre-treatment with Citogenex prevents the intestinal damage induced by TNBS.

This paper reviews the composition of colostrum and the potential preventive and therapeutic use of this "first milk" for treating various gastrointestinal disorders in humans. Colostrum is a complex biological liquid that is richer in antimicrobial peptides, immune-regulating compounds and growth factors than the subsequent mature milk. The main functions of colostrum are to provide essential nutritional components, strengthen the natural defense system, modulate immune response, balance intestinal microbiota and enhance the growth and repair of several tissues. Several studies and clinical trials carried out both in vitro and in vivo on humans and animals suggest the clinical benefits of bovine colostrum (BC) supplementation in gastro-intestinal diseases. Despite the encouraging results, further well-designed studies are required in order to confirm these effects, the dose and duration of treatment. Colostrum is safe since there are no contraindications regarding high dose levels and few side effects of clinical relevance have been reported. In conclusion, in the near future, colostrum-based supplements may play a complementary role to synthetic drugs in the prevention and treatment of various gastrointestinal disorders.