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CD19+CD5+ regulatory B cells regulate immune responses by producing IL-10. IL-10-producing regulatory B cell (Br1) responses by allergen stimulation were investigated in human food allergy. Six milk allergy patients and eight milk-tolerant subjects were selected according to DBPCFC. PBMCs were stimulated by casein in vitro and stained for intracellular IL-10 and apoptosis. In response to allergen stimulation, Br1 decreased from 26.2 ± 18.3 to 15.5 ± 8.9% (p = 0.031, n = 6) in the milk allergy group and increased from 15.4 ± 9.0 to 23.7 ± 11.2% (p = 0.023, n = 8) in the milk-tolerant group. Apoptotic non-IL-10-producing regulatory B cells increased from 21.8 ± 9.3 to 38.0 ± 16.1% (p = 0.031, n = 6) in the milk allergy group and unchanged from 28.8 ± 13.8 to 28.0 ± 15.0% (p = 0.844, n = 8) in the milk-tolerant group. Br1 may be involved in the immune tolerance of food allergies by producing IL-10 and simultaneously undergoing apoptosis in humans. The exact roles for Br1 in immune tolerance needs to be further investigated.  相似文献   

3.
B cells have regulatory functions in immune responses. Antigen-specific responses of B cell subsets by allergen stimulation ex vivo were examined in milk allergy of late eczematous reactions. Eight milk allergy subjects and 13 milk tolerant subjects were selected by DBPCFC. PBMCs were stimulated by casein ex vivo and stained for B cell subsets using monoclonal antibodies. CD19+ B cells unchanged from 8.7 ± 3.8% to 8.0 ± 5.1% (p = 0.504, n = 8) in the milk allergy group and decreased in the milk tolerant group from 8.5 ± 3.2% to 5.0 ± 1.6% (p = 0.001, n = 13). The fraction of apoptotic B cells in B cells significantly decreased 4.4 ± 3.1% to 1.3 ± 0.4% (p = 0.027, n = 4) in the allergy group and insignificantly increased from 2.8 ± 0.6% to 5.4 ± 2.6% (p = 0.059, n = 6) in the milk tolerant group. CD5+ regulatory B1 cell% in B cells decreased in milk allergy subjects from 36.2 ± 5.0% to 31.0 ± 5.7% (p = 0.010) and unchanged in milk tolerant subjects from 41.6 ± 10.2% to 43.8 ± 10.0% (p = 0.413). IL-10 producing CD19+CD5+ regulatory B cell% in CD19+CD5+ regulatory B cells significantly decreased from 24.9 ± 6.5% to 13.8 ± 5.6% (p = 0.002, n = 5) by casein stimulation in milk allergy group and unchanged from 44.8 ± 11.3% to 43.9 ± 10.0% (p = 0.297, n = 5) in the milk tolerant group. B cell subset responses to IL-4 and IL-5 were also similar in both groups. B cell subset changes seemed to have diagnostic value. Exact immunologic roles of regulatory CD5+ B1 cells need further investigation.  相似文献   

4.
Restricting-type anorexia nervosa (AN-R) is characterized by chronic food restriction and severe emaciation due to various cognitive biases such as a distorted self-image. In spite of several treatments, AN-R continues to be a refractory disease because of its unknown pathogenesis. Although previous studies have shown that changes in feeding regulatory peptides such as ghrelin are involved in anorexia, few reports have described the relationship between AN-R and nesfatin-1, a recently identified satiety peptide. Therefore, we examined the plasma nesfatin-1 levels in AN-R patients to determine its role in AN-R. A total of 15 women participated in the study; 7 patients with AN-R and 8 age-matched healthy controls (average BMI, 13.02 ± 0.30 vs. 21.57 ± 0.48, respectively). Our results showed that plasma nesfatin-1 levels were significantly lower in AN-R group than in control group (6.23 ± 0.70 ng/ml vs. 8.91 ± 0.85 ng/ml, respectively, P < 0.05). Plasma acyl ghrelin and des-acyl ghrelin levels were significantly higher in AN-R group than in control group (acyl ghrelin: 62.4 ± 10.15 fmol/ml vs. 27.20 ± 5.60 fmol/ml, P < 0.01 and des-acyl ghrelin: 300.17 ± 55.95 fmol/ml vs. 107.34 ± 40.63 fmol/ml, P < 0.05). Although AN-R is associated with emaciation for a prolonged period, our result suggested that nesfatin-1 levels may be regulated by nutrition status and response to starvation.  相似文献   

5.
Relatively high levels of d-alanine (d-Ala), an endogenous d-amino acid, have been found in the endocrine systems of several animals, especially in the anterior pituitary; however, its functional importance remains largely unknown. We observed d-Ala in islets of Langerhans isolated from rat pancreas in significantly higher levels than in the anterior/intermediate pituitary; specifically, 180 ± 60 fmol d-Ala per islet (300 ± 100 nmol/g islet), and 10 ± 2.5 nmol/g of wet tissue in pituitary. Additionally, 12 ± 5% of the free Ala in the islets was in the d form, almost an order of magnitude higher than the percentage of d-Ala found in the pituitary. Surprisingly, glucose stimulation of the islets resulted in d-Ala release of 0.6 ± 0.5 fmol per islet. As d-Ala is stored in islets and released in response to changes in extracellular glucose, d-Ala may have a hormonal role.  相似文献   

6.
Tumor necrosis factor α (TNF-α) is an essential player in infection with Leishmania, controlling inflammatory lesion and parasite killing. We recently have shown the leishmanicidal activity of transmembrane form of TNF (mTNF) derived from allogeneic natural killer (NK) cells in experimental visceral leishmaniasis. Allogeneic macrophages and human monocytes derived mTNF has significantly higher antileishmanial activity compared to allogeneic NK cells. Unlike NK cells, syngeneic macrophages also possess antileishmanial activity, although degree of activity is significantly less compared to allogeneic macrophages. Cellular therapy by intravenous transfer of allogeneic macrophages enhances leishmanicidal effect against the established infection in susceptible animal by reducing the splenic parasite burden to 28.3 ± 4.71 × 105 compared to 256.00 ± 17.36 × 105 in control group. In vivo treatment with anti-mouse TNF-α reduces the therapeutic efficacy of the allogeneic macrophages by increasing the parasite load in spleen of infected mice. These results demonstrated that allogeneic and xenogeneic macrophages induce cytokine mediated protective mechanism against infected macrophages via TNF-α in vitro and, possibly in vivo. The macrophage mediated protective role in absence of T cell help demonstrate an unique property of the mononuclear phagocytes in controlling infection and inflammation in visceral leishmaniasis, despite being acts as a host cell for the same parasite.  相似文献   

7.
Summary The phenotypic expression of the proteoglycan of human mast cells in the nasal mucosa and normal skin was analysed using histochemical techniques. Nasal mucosa was obtained from normal subjects, from patients with seasonal allergic rhinitis before and during the pollen season and from patients with nasal polyps. In the latter groups, specimens were taken from both polyp tissue and adjacent nasal mucosa. Formaldehyde treatment blocked the cationic dye binding in 75–84% of the mast cells located in the nasal mucosa, as compared to the optimum fixation with IFAA (iso-osmotic formaldehyde-acetic acid). A significantly lower degree of blocking of dye binding was obtained in the human skin where 45% of the mast cells were susceptible to formaldehyde treatment (P<0.01). The mast cells of the polyp tissue also showed a relatively low degree of blocking (54%), which was significantly lower than the blocking of mast cells of the nasal mucosa taken from the same individuals (P<0.05). Staining of serial tissue sections in Alcian Blue containing graded concentrations of MgCl2 was used to determine the critical electrolyte concentration (CEC) of the dye binding, defined as the salt concentration at which the staining of 50% of the mast cells is extinguished. The CEC of the skin mast cells was 0.64m MgCl2 which is significantly higher than that of the mast cells of the nasal mucosa of normal subjects [0.49m (P<0.05)], allergic subjects [0.52m (P<0.01)], patients with polyp disease [0.52m (P<0.01)] and the polyp tissue proper [0.57m (P<0.05)]. This implies that mast cells of the nasal mucosa contain glycosaminoglycans of a relatively lower charge density and/or molecular size than the connective tissue mast cells found in the human skin. A similar difference has been observed between rat mucosal mast cells, containing a chondroitin suphate proteoglycan, and rat connective tissue mast cells which contain a heparin proteoglycan. However, unlike the rat mucosal cells, the mast cells of the human nasal mucosa showed a weakly fluorescent Berberine binding and, like the rat connective tissue mast cells, entirely lost the ability to bind Toluidine Blue after treatment with nitrous acid. Such treatment results in a deaminative cleavage of heparin and heparan sulphate, but does not degrade chondroitin sulphate. These results provide further evidence of the existence of a distinctive mucosal mast cell phenotype also in man. It is suggested that the lower CEC of the mucosal mast cells is an expression of a content of haparan sulphate, while the relatively higher CEC of the skin mast cells is compatible with a content of heparin.  相似文献   

8.
In this study, a promising system consisting of up-flow anaerobic sludge blanket (UASB) reactor followed by down-flow hanging sponge (DHS) reactor was investigated for onion dehydration wastewater treatment. Laboratory experiments were conducted at two different phases, i.e., phase (1) at overall hydraulic retention time (HRT) of 11 h (UASB reactor: 6 h and DHS reactor: 5 h) and phase (2) at overall HRT of 9.4 h (UASB reactor: 5.2 h and DHS reactor: 4.2 h). Long-term operation results of the proposed system showed that its overall TCOD, TBOD, TSS, TKN and NH4N removal efficiencies were 92 ± 5, 95 ± 2, 95 ± 2, 72 ± 6 and 99 ± 1.3%, respectively (phase 1). Corresponding values for the 2nd phase were 85.4 ± 5, 86 ± 3, 87 ± 6, 65 ± 8 and 95 ± 2.8%. Based on the available results, the proposed system could be more viable option for treatment of wastewater generated from onion dehydration industry in regions with tropical or sub-tropical climates and with stringent discharge standards.  相似文献   

9.
BACKGROUND: Prostaglandin D2 (PGD2) is released from mast cells during the allergic response. OBJECTIVE: Since PGD2 has been shown to induce nasal congestion in humans, we investigated the distribution of hematopoietic prostaglandin D synthase (PGDS) and the two PGD2 receptors, DP and CRTH2 in human nasal mucosa from healthy subjects and subjects suffering from polyposis, a severe form of chronic rhinosinusitis. METHODS: DP mRNA expression was detected by in situ hybridization while PGDS, CRTH2 and various leukocyte markers expression were revealed by immunohistochemistry. RESULTS: In the normal mucosa, PGDS was only detected in few resident mast cells while CRTH2 was undetectable. In contrast, DP receptor mRNA was detected in epithelial goblet cells, serous glands and in the vasculature. In the nasal mucosa of subjects suffering from polyposis: (1) PGDS was detected in mast cells and other large infiltrating inflammatory cells, (2) both DP mRNA and CRTH2 were detected in eosinophils and (3) CRTH2 was detected on a subset of infiltrating T cells. Although DP mRNA could not be detected in the T cells invading the nasal mucosa, it was found to be expressed in the T cells present in the lymph node and the thymus from normal individuals. CONCLUSION: This study indicates that cells capable of producing PGD2 are present in the nasal mucosa and that both PGD2 receptors, DP and CRTH2, might play a role in inflammatory disease of the upper airways.  相似文献   

10.
The enzyme that acylates ghrelin was recently identified in mice as the fourth member of the membrane-bound O-acyltransferases superfamily (MBOAT4) and named ghrelin-O-acyltransferase (GOAT). Only one report showed GOAT mRNA expression in ghrelin-expressing cells of the mouse stomach. We investigated the distribution of GOAT protein in peripheral tissues and co-expression with endocrine markers in the gastric mucosa using a custom-made anti-GOAT antibody. Tissues were collected from male Sprague-Dawley rats and C57BL/6 mice. Western blot revealed two immunoreactive bands in rat and mouse gastric corpus mucosal proteins, a 50 kDa band corresponding to the GOAT protein and a 100 kDa band likely corresponding to a dimer. Western blot also detected GOAT in the plasma and levels were strongly increased after 24-h fasting in mice and slightly in rats. GOAT-immunoreactive cells were located in the gastric corpus mucosa and the anterior pituitary gland, whereas other peripheral tissues of rats and mice examined were negative. In mice, GOAT-immunoreactive cells were mainly distributed throughout the middle portion of the oxyntic glands, whereas in rats they were localized mainly in the lower portion of the glands. Double labeling showed that 95 ± 1% of GOAT-immunoreactive cells in mice co-labeled with ghrelin, whereas in rats only 56 ± 4% of GOAT-positive cells showed co-expression of ghrelin. The remainder of the GOAT-immunopositive cells in rats co-expressed histidine decarboxylase (44 ± 3%). No co-localization was observed with somatostatin in rats or mice. These data suggest species differences between rats and mice in gastric GOAT expression perhaps resulting in a different role of the MBOAT4 enzyme in the rat stomach. Detection of GOAT in the plasma raises the possibility that ghrelin octanoylation may occur in the circulation and the fasting-induced increase in GOAT may contribute to the increase of acylated ghrelin after fasting.  相似文献   

11.
The arrangement of the superficial facial veins enables blood flow from the nasal cavity into the peripheral circulation by two pathways: through the frontal vein into the cavernous sinus and through the facial vein into the external jugular vein. The current study was designed to determine whether estradiol and progesterone affect the vascular tone of the superficial veins of the nose and face in cycling gilts (Sus scrofa f. domestica) and to analyze the immunolocalization of progesterone receptors and estradiol receptors in these veins. The influence of hormones on vascular tension differed depending on the type of vessel and the phase of the estrous cycle. Estradiol decreased vascular tension in the nasal vein during the follicular phase (P < 0.05) and increased tension in the frontal vein during the luteal phase (P < 0.05). Progesterone increased the vascular tension of the frontal vein (P < 0.05) and decreased the tension of the other veins (P < 0.05) in both phases of the cycle. Expression of estradiol receptor β but not of progesterone receptor was observed in the superficial veins of the nose and face. In conclusion, the effect of ovarian steroid hormones on the vascular tension of the superficial veins of the nose and face in female pigs as well as the reactivity of these veins to steroid boar pheromones can affect the blood supply from the nasal cavity to the venous cavernous sinus. We propose that the ovarian steroid hormones that modulate the vascular tension of the nasal and facial veins may also influence the action of boar pheromones absorbed into the nasal mucosa in gilts and may reach the brain via local destination transfer.  相似文献   

12.
Low concentrations of cigarette smoke induced DNA damage and repair without leading to apoptosis in human bronchial epithelial cells. Higher concentrations of cigarette smoke, however, could induce either apoptosis or necrosis. The current study demonstrated that 15% cigarette smoke extract (CSE) induced apoptosis as evidenced by DNA content profiling (17.8 ± 2.1% vs 10.2 ± 1.6% of control, p < 0.05), LIVE/DEAD staining (60.2 ± 2.1% viable cells in CSE-treated vs 86.5 ± 2.3% in control cells, p < 0.05), and COMET assay (24.3 ± 0.6% of Apoptotic Index in the cells treated with CSE vs 4.7 ± 0.6% of control, P < 0.05). Hepatocyte growth factor (HGF) significantly blocked the cigarette smoke-induced apoptosis as shown by DNA profiling (10.8 ± 1.5% of CSE + HGF, p < 0.05), LIVE/DEAD staining (78.5 ± 1.2% in CSE + HGF treated cells, p < 0.05), and COMET assay (Apoptotic Index: 10.0 ± 0.8% in CSE + HGF treated cells, P < 0.05). This protective effect of HGF on CSE-induced apoptosis was abolished by PI3K inhibitors, wortmannin and LY294002, and by introduction of the dominant negative AKT into the cells. Furthermore, CSE plus HGF could induce phosphorylation of AKT Thr 308 and the pro-apoptotic protein, BAD. These results suggest that HGF modulates cell survival in response to cigarette smoke exposure through the PI3K/AKT signaling pathway.  相似文献   

13.
Crustacean hyperglycemic hormone (CHH) was originally identified in a neuroendocrine system-the X-organ/sinus gland complex. In this study, a cDNA (Prc-CHH) encoding CHH precursor was cloned from the hemocyte of the crayfish Procambarus clarkii. Analysis of tissues by a CHH-specific enzyme-linked immunosorbent assay (ELISA) confirmed the presence of CHH in hemocytes, the levels of which were much lower than those in the sinus gland, but 2 to 10 times higher than those in the thoracic and cerebral ganglia. Total hemocytes were separated by density gradient centrifugation into layers of hyaline cell (HC), semi-granular cell (SGC), and granular cell (GC). Analysis of extracts of each layer using ELISA revealed that CHH is present in GCs (202.8 ± 86.7 fmol/mg protein) and SGCs (497.8 ± 49.4 fmol/mg protein), but not in HCs. Finally, CHH stimulated the membrane-bound guanylyl cyclase (GC) activity of hemocytes in a dose-dependent manner. These data for the first time confirm that a crustacean neuropeptide-encoding gene is expressed in cells essential for immunity and its expression in hemocytes is cell type-specific. Effect of CHH on the membrane-bound GC activity of hemocyte suggests that hemocyte is a target site of CHH. Possible functions of the hemocyte-derived CHH are discussed.  相似文献   

14.
N-Arachidonoylethanolamine (AEA, anandamide) was the first endocannabinoid to be identified and has since become associated with the mediation of several physiological functions and disease states. AEA has been isolated from numerous tissues and biofluids, in the low nanomolar range, using lipid extraction techniques with organic solvents. These techniques require the drying down of relatively large volumes of solvents, making them unsuitable for high-throughput analysis. Here we describe a solid-phase extraction (SPE) method for the investigation of AEA concentrations in human plasma, serum, milk, urine, amniotic fluid, peritoneal fluid, saliva, follicular fluid, and fluid from an ovarian cyst. AEA was detected in serum and plasma from blood isolated from 20 adult women (means ± standard deviations: 0.68 ± 0.29 and 0.64 ± 0.28 nM, respectively), from pregnant women at term (1.37 ± 0.42 nM), and from umbilical vein (1.26 ± 0.33 nM) and umbilical artery (1.14 ± 0.35 nM), in milk (0.12 ± 0.05 nM) and from amniotic (0.03 ± 0.02 nM), peritoneal (0.93 ± 0.27 nM), follicular (1.17 ± 0.51 nM), and ovarian cyst (0.32 ± 0.01 nM) fluids. AEA was undetectable in saliva and urine. The 60% AEA extraction efficiency achieved with SPE from plasma was superior to the 19% efficiency achieved using the existing organic solvent extraction method. Limits of quantification and detection for AEA were also improved dramatically using SPE (8 and 4 fmol/ml) compared with organic extraction (25 and 18.75 fmol/ml plasma). These improvements allow the use of smaller plasma samples with SPE. Intra- and interday variability were comparable, and the mean AEA concentration of pooled plasma samples (1.18 nM, n = 15) was identical with the two techniques. Similarly, when 56 plasma samples from laboring and nonlaboring women were analyzed using both techniques, no extraction method-dependent differences were observed. Consequently, we provide evidence for a robust SPE technique for the extraction of AEA from biomatrices to replace the existing liquid extraction methods, with the SPE technique being superior in terms of speed, extraction efficiency, and sample size required.  相似文献   

15.
Regulation of apoptosis in mast cells   总被引:6,自引:0,他引:6  
Apoptosis is a physiological process of cell death that occurs in all multicellular organisms. Its dysregulation has been postulated as one of the main causes in the development of diseases such as cancer, AIDS, autoimmune diseases and allergy. Apoptosis has been mainly studied in the inflammatory cells that participate in the late and chronic stages of allergy (eosinophils, neutrophils, lymphocytes and macrophages) as a new way to elucidate the pathogenesis of this disease. Nevertheless, much less it is known about the regulation of apoptosis in the initiators of the allergic process: The Mast Cells. In normal conditions, mast cells are described as long-living cells that keep a constant number of cells in tissues. However, increased numbers of mast cells are observed in the late phase of asthma and in both the inflammatory and in the repair/remodeling stage of various inflammatory/fibrotic disorders. In this report, we discuss the possible mechanisms that regulate the apoptotic process in normal conditions and disease, such as survival factors and death receptors. A link between mast cell activation, during the early stages of the allergic process, and triggering of anti-apoptotic signaling pathways is also suggested as an important contributor to the extended life of mast cells.  相似文献   

16.
This initial report presents a neonatal rat model with exposure to a transient intermittent hypoxia (IH), which results in a persisting diabetes-like condition in the young rats. Twenty-five male pups were treated at postnatal day 1 with IH exposure by alternating the level of oxygen between 10.3% and 20.8% for 5 h. The treated animals were then maintained in normal ambient oxygen condition for 3 week and compared to age-matched controls. The IH treated animals exhibited a significantly higher fasting glucose level than the control animals (237.00 ± 19.66 mg/dL vs. 167.25 ± 2.95 mg/dL; P = 0.003); and a significantly lower insulin level than the control (807.0 ± 72.5 pg/mL vs. 1839.8 ± 377.6 pg/mL; P = 0.023). There was no difference in the mass or the number of insulin producing beta cells as well as no indicative of inflammatory changes; however, glucose tolerance tests showed a significantly disturbed glucose homeostasis. In addition, the amount of C-peptide secreted from the islets harvested from the IH animals were decreased significantly (from 914 pM in control to 809 pM in IH; P = 0.0006) as well. These observations demonstrate that the neonatal exposure to the IH regimen initiates the development of deregulation in glucose homeostasis without infiltration of inflammatory cells.  相似文献   

17.
Removing a horse from its social group may be considered risky, both for the handler and the horse, because other horses can interfere in the catching process. The main aim of this study was to identify where and when these risk situations occur while removing a horse from its group. A potential risk situation was defined by the closeness of loose horses in the group or by any physical contact with them. Whether the number of horses following would be influenced by the social rank of the horse being led out, and whether more horses would follow to the gate when a larger proportion of the group was removed compared to when a single horse was taken out were also investigated.Thirty-two mares (1-2 years) were kept in groups of four. All horses were taken out of their home paddock twice alone (64 tests) and twice with a companion (32 tests). One handler (or two handlers when two horses were removed) was asked to approach (phase 1) and catch the target horse (phase 2), walk it to the centre of the paddock and remain stationary at a post for 30 s (phase 3), walk to the paddock entrance (phase 4) and through the gate (phase 5). The number of horses following, and the number of loose horses in proximity (<2 m, 2-5 m) to the target horse and handler was estimated, and horse-horse and horse-human interactions were recorded continuously for the five scoring phases.Significantly more loose horses were within 2 m of a single target horse during the phases approach (mean ± SD: 1.5 ± 0.8), catch (1.6 ± 0.9) and post (1.7 ± 0.7) than during walk (1.0 ± 0.5) and gate (1.1 ± 0.6). Rank did not influence the number of horses following to the gate (high rank: 2.4 ± 0.7; lower rank: 2.0 ± 1.0; P = 0.396) and interactions between horses were rare. A greater proportion of the loose horses followed when two horses (0.9 ± 0.2) were removed compared to when a single horse (0.7 ± 0.3) was taken out (P = 0.011).In conclusion, maintaining a distance to other horses in the group by reducing the time being relatively stationary, so giving loose horses fewer chances to approach, is likely to contribute to improved handler's safety. Removing a small proportion of the group may also decrease the probability of the other horses following.  相似文献   

18.
19.
The sympathetic-catecholamine system is involved in the regulation of hepatic metabolic pathways mainly through cAMP-linked β2-adrenoceptors (β2-ARs) in humans and to a lesser extent through cAMP-independent mechanisms, but no information is available about the possible biochemical changes of β2-ARs and their signalling pathways in human colorectal cancer (CRC) and colorectal cancer hepatic metastases (CRCHM). Changes in density and distribution of β-ARs as well as in post-receptor signalling components were studied in membranes of human liver with CRCHM, and for comparison, in membranes of nonadjacent, non-metastatic human liver (NA-NM) obtained from 13 patients, using binding and competition binding studies. Studies were also carried out using normal and cancerous human colon tissues. In CRCHM, the density of β-ARs (Bmax) was significantly reduced, compared to NA-NM liver tissues (40.09 ± 2.83 vs. 23.09 ± 3.24 fmol/mg protein; P < 0.001). A similar decrease in the β-AR density was observed in the colon with primary colorectal cancer compared to healthy colon (37.6 ± 2.2 vs. 23.8 ± 3.5 fmol/mg protein), whereas the affinity of ICYP binding to the receptor remained unaffected. Desensitized β-ARs were uncoupled from stimulatory G-protein (GS), as total density of β-adrenoceptors in the high affinity state was significantly reduced. Concomitantly, CRCHM elicited decrease in the catalytic adenylate cyclase (AC) activity (cAMP formation) in response to isoproterenol plus GTP or forskolin or NaF. In NA-NM and CRCHM liver, the inhibition–concentration curves of ICI 118.551 showed the presence of a homogeneous population of the β2-AR subtypes. Neither the binding patterns nor the inhibition constant (Ki) of ICI 118.551 were altered in CRCHM. In CRCHM, the hepatic β-AR-G-protein(s)-AC signalling system was markedly impaired, thus, these changes may well influence β-AR-mediated functions in both organs.  相似文献   

20.
This study compared the effects of slow and fast freezing of testicular tissue of wild animals collected at post-mortem on testicular structure and testicular sperm. The testes of seven animals that had died in captivity; three felids (jungle cat, lion and leopard), two cervids (rusa deer and fea’s muntjac) and two bovids (Sumatran serows) were cryopreserved using slow- and fast-freezing protocols. There were greater reductions in the integrity of the sperm membrane and DNA in tissues cryopreserved using slow freezing compared to fast freezing (membrane integrity reduced by 21.5 ± 12.4% vs. 13.0 ± 6.9%, = 0.11 and DNA integrity reduced by 22.7 ± 16.3% vs. 6.6 ± 6.3%, = 0.13). Histologically, there were similar degrees of detachment and shrinkage of the seminiferous tubules whereas, TUNEL assay revealed a tendency towards more apoptotic changes in the intra-tubular cells of tissues frozen using fast freezing compared to slow freezing (= 0.09). In conclusion, fast freezing tended to cause less damage to testicular sperm but its protective effect on intra-tubular cells was likely compromised. This is the first report of gamete recovery in the wild and of the comparison in various wildlife species, between testicular tissues cryopreserved using different protocols.  相似文献   

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