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1

Effect of platelet-activating factor on motility parameters and plasmalemma integrity of boar spermatozoa

100%
Kordan W., Strzezek J.
Animal Science Papers and Reports
|
2002
|
tom 20
|
nr 1
2
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Role of leukotrienes and platelet activating factor in gastric mucosal damage and repair

86%
Konturek S. J., Brzozowski T.
Journal of Physiology and Pharmacology
|
1991
|
tom 42
|
nr 2
Gastric mucosal integrity depends upon the balance between „aggressive” factors and „defensive” mechanisms. The formation of mucosal lesions results from the disruption of defense lines, including the breaking of unstirred mucus layer, the reduction of surface hydrophobicity, extensive exfoliation of surface epithelium, penetration of offending agents deeply into the mucosa and damage to the microvessels. The release of proinflam- matory and vasoactive mediators such as leukotrienes (LT), thromboxanes, platelet activating factor (PAP), endothelins and others has been thought to be involved in the pathomechanism of mucosal injury, especially damage to the micro vascular endothelium, increased vascular permeability, reduction in mucosal blood flow, vascular stasis, tissue ischemia and glandular cell necrosis. This paper reviews the mechanisms and possible pathogenetic implication of two related compounds, LT and PAP in acute mucosal injury by topical irritants such as ethanol, aspirin, bile salts and by stress. LT and PAP arise from similar membrane phospholipids and may regulate the biosynthesis of one another in the damaged mucosa. Although pharmacological studies have clearly demonstrated the noxious effects of cysteinyl LT and PAP on the mucosa, especially when exposed to topical irritants, recent publications have challenged the primary role of these mediators in the pathogenesis of mucosal lesions and ulcerations because the treatment with agents that selectively antagonize their biosynthesis or the receptor sites at the target cells did not always interrupt the chain of events leading to mucosal injury. The role of these mediators in the mucosal repair processes has been little studied but both cysteinyl LT and PAP seem to delay the restitution and healing of the mucosa. Further studies are necessary to clarify to what extent the biosynthesis of LT and PAP and the pharmacological inhibition of their action on the target tissues is related to noxious, protective and reparative events in the mucosa exposed to mild irritants and ulcerogens.
3

A polypeptide from protein complex of platelet-activating factor acetylhydrolase [PAF-AH] of boar seminal plasma belongs to a family of adhesion proteins

86%
Kordan W., Wysocki P., Strzezek J.
Animal Science Papers and Reports
|
2004
|
tom 22
|
nr 3
The N-terminal amino acid sequence was analysed of 43 kDa polypeptide, component of the protein complex of PAF acetylhydrolase (PAF-AH) isolated from boar seminal plasma. Amino acid sequence of the 43 kDa did not show homology with the characteristic sequences of PAFAH isolated from other sources. However, 43 kDa showed a high homology with the characteristic sequences of IgG-binding proteins as well as with zona pellucida-binding adhesion proteins - zonadhesions. The results indicate that the isolated 43 kDa polypepfide belongs to the family of adhesion proteins, involved in the processes accompanying egg fertilization.
4
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Involvement of platelet activating factor in immediate heart response to lipopolysaccharide

86%
Jakubowski A., Olszanecki R., Chlopicki S.
Journal of Physiology and Pharmacology
|
2004
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tom 55
|
nr 2
Although lipopolysaccharide (LPS) is recognized to induce a biphasic cardiovascular response its mechanism is not fully elucidated. In this study we analysed the involvement of PAF, TXA2 and cysteinyl leukotrienes (cysLTs) in the acute cardiovascular effects of LPS in the isolated rat heart as well as in delayed phase of LPS response using a surrogate cellular model of the induction of NOS-2 by LPS in mouse macrophages. Perfusion of rat hearts with LPS resulted, in an immediate fall in heart contractility and coronary flow by 2.5 ± 0.59 ml min-1 and 560 ± 81 mmHg sec-1, respectively. This response was fully blocked by platelet activating factor (PAF) antagonist - WEB 2170 and partially inhibited, by inhibitor of cyclooxygenase (indomethacin) or by inhibitor of thromboxane synthase (camonagrel). The inhibition of leukotriene synthesis (BAY x1005) or cysLTs receptors (BAY x7195) was without effect. Administration of stable PAF analog (methylcarbamyl-PAF - MC-PAF) alone, mimicked heart response to LPS. In cultured mouse macrophages, MC-PAF did not induce NOS-2 expression and when given with LPS it slightly potentiated NOS-2 induction by LPS. However, in presence of WEB 2170 NOS-2 induction by LPS was inhibited in a dose-dependent manner. Inhibition of cyclooxygenase and leukotriene pathways had no effect on NOS-2 induced by LPS. These results indicate that PAF and TXA2 but not cysLTs mediate the instant heart response induced by LPS, while PAF alone mediates a delayed NOS-2 induction by LPS. Accordingly, PAF may constitute the mediator that links acute and delayed phases of LPS-induced cardiovascular response.
5
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Platelet activating factor [PAF] inhibitor [TCV-309] reduces caerulein - and PAF-induced pancreatitis. A morphologic and functional study in the rat

86%
Tomaszewska R., Dembinski A., Warzecha Z., Banas M., Konturek S. J., Stachura J.
Journal of Physiology and Pharmacology
|
1992
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tom 43
|
nr 4
Caerulein-induced acute pancreatitis was studied in rats. Consistent with this type of acute pancreatitis morphological (edema, leukocytic infiltration and acinar cell vaculization) and biochemical (increase in pancreatic protein content, PAF release and serum amylase) changes developed 5 hours after caerulein administration. In addition increase in pancreatic weight and decrease in pancreatic blood flow were noticed. PAF administration caused pancreatic damage similar in some parameters to caerulein-induced pancreatitis, along with reduction of pancreatic blood flow, increase in pancreatic protein content, and serum amylase. TCV-309, a selective PAF antagonist, administered prior to caerulein and/or PAF, reduced caerulein-induced pancreatitis and prevented PAF-induced pancreatitis. Results of our present studies indicate the crucial role of PAF in pathogenesis of experimental acute pancreatitis.
6
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Platelet-activating factor mediates Porphyromonas gingivalis lipopolysaccharide interference with salivary mucin synthesis via phosphatidylinositol 3-kinase-dependent constitutive nitric-oxide synthase activation

86%
Slomiany B. L., Slomiany A.
Journal of Physiology and Pharmacology
|
2004
|
tom 55
|
nr 1,1
Platelet -activating factor (PAF), a phospholipid-derived messenger molecule, is now recognized as the most proximal mediator of cellular events triggered by bacterial lipopolysaccharide (LPS) stimulation. In this study, we assessed the role of PAF in the disturbances in salivary mucin synthesis evoked by LPS of periodontopathic bacterium, P. gingivalis. Using primary culture of mucous acinar cells of sublingual salivary gland, we show that a specific PAF antagonist, BN52020, prevents in a dose-dependent fashion (up to 83.7%) the LPS-induced reduction in mucin synthesis, and the effect is reflected in a marked decrease in the LPS-induced apoptosis (74.8%), NO generation (82.6%), and the expression of TNF-alpha (76.1%). The impedance by BN52020 of the LPS inhibitory effect on mucin synthesis was blocked by wortmannin, an inhibitor of phosphatidylinositol 3-kinase (PI3K), which also obviated the inhibitory effect of BN52020 on the LPS-induced upregulation in apoptosis, TNF-alpha , and NO. A potentiation in the impedance by BN52020 of the LPS detrimental effect on mucin synthesis was however attained with NOS-2 inhibitor, 1400W, while cNOS inhibitor, L-NNA caused a reduction in the impedance effect of BN52020. However, while 1400W and BN52020 countered the potentiating effect of wortmannin on the LPS-induced decrease in mucin synthesis, a further exacerbation of the effect of wortmannin occurred in the presence of L-NNA. The findings implicate PAF as a pivotal factor affecting the extent of pathological consequences of P. gingivalis infection on salivary glands capacity for mucin production, and suggest that its release in response to the LPS serves as a negative regulator of PI3K controlling the pathway of cNOS activation.
7

Effect of platelet-activating factor on motility, plasmalemma integrity, the process of capacitation and acrosome reaction of fresh and cryopreserved boar spermatozoa

72%
Kordan W., Lecewicz M., Tobolski J.
Polish Journal of Veterinary Sciences
|
2009
|
tom 12
|
nr 2
175-181
The aim of the present study was to establish the effects of platelet-activating factor (PAF) on selected movement parameters, plasmalemma integrity, capacitation process and acrosome reaction in cryopreserved boar spermatozoa. A positive effect of PAF addition to cryopreserved semen on sperm motility was demonstrated, particularly with the application of phospholipid concentration of 1 x 10-6M-1 x 10-5M. A moderate induction of plasmalemma damage of cryopreserved spermatozoa was observed when PAF was used at a low concentration (1 x 10-8M-1 x 10-7M). The rate at which PAF induced the process of capacitation was inversely proportional to its concentration in the sample (the highest for the concentration of 1 x 10-8M, and the lowest at 1 x 10-5M). In turn, the strongest induction of acrosome reaction of spermatozoa was observed in samples with the addition of PAF at a concentration of 1 x 10-7M. The results obtained suggest that the application of PAF supplement to post-thawed boar semen can be used as a laboratory test of the ability of spermatozoa to induce the acrosome reaction.
8

Lysophosphatidylcholine triggers cell differentiation in the protozoan parasite Herpetomonas samuelpessoai through the CK2 pathway

72%
Dutra F. L., Vieira D. P., Coelho F. S., Adade C. M., Atella G. C., Silva Neto M. A. C., Lopes A. H.
Acta Parasitologica
|
2020
|
tom 65
|
nr 1
9

Platelet-activating factor changes in phospholipid extracts from the plasma, peripheral blood mononuclear cells and bone marrow mononuclear cells of patients with acute leukemia - A 31P MRS in vitro study

72%
Kuliszkiewicz-Janus M., Tuz M. A., Kielbinski M., Baczynski S., Jazwiec B., Sladowska H.
Cellular and Molecular Biology Letters
|
2008
|
tom 13
|
nr 1
58-66
The aim of this investigation was to evaluate the changes in PAF concentrations in the plasma, PBMC and BMMC of patients with acute lymphoblastic leukemia (ALL) and acute myeloblastic leukemia (AML). The plasma was from 23 healthy volunteers (HV) and 44 patients with AL (16 ALL, 28 AML). The PBMC were from 15 HV and 55 patients with AL (18 ALL, 37 AML), and the BMMC from 40 patients with AL (11 ALL, 29 AML). Methanol-chloroform phospholipid extraction from 60 × 106 cells (PBMC or BMMC) was performed according to a modified version of Folch’s method. 31P MRS data was obtained on an AMX 300 Bruker spectrometer (7.05 T). The PAF concentration in the plasma of the patients with ALL or AML was lower than that for the healthy volunteers. The PAF concentration in the plasma of the patients with ALL did not differ significantly from that of the patients with AML. In the case of both the PBMC and BMMC, the PAF concentration was significantly diminished in patients with ALL relative to the concentration for those with AML and for the healthy volunteers. No differences were observed in the PAF concentrations for the AML patients and the healthy volunteers.
10
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Effect of platelet activating factor (PAF) supplementation in semen extender on viability and ATP content of cryopreserved canine spermatozoa

72%
Kordan W., Lecewicz M., Strzezek R., Dziekonska A., Fraser L.
Polish Journal of Veterinary Sciences
|
2010
|
tom 13
|
nr 4
The aim of this study was to investigate the effect of platelet activating factor (PAF) on the quality characteristics of cryopreserved canine spermatozoa. Cryopreserved semen of 5 mixed-breed dogs was treated with different concentrations of exogenous PAF (1 × 10⁻³M, 1 × 10⁻⁴M, 1 × 10⁻⁵M and 1 × 10-6M) and examined at different time intervals (0, 30, 60 and 120 min). Cryopreserved semen treated without PAF was used as the control. Sperm quality was evaluated for motility (computer-assisted semen analysis, CASA), mitochondrial function (JC-1/PI assay) and plasma membrane integrity (SYBR-14/PI assay and Hoechst 33258). Also, ATP content of spermatozoa was determined using a bioluminescence assay. Treatment of cryopreserved semen with 1 × 10⁻³ M PAF at 120 min of incubation resulted in significantly higher total sperm motility compared with the control. It was observed that PAF-improved total sperm motility was concurrent with enhanced sperm motility patterns after treatment of cryopreserved semen. Treatment of cryopreserved semen with PAF did not improve either sperm mitochondrial function or plasma membrane integrity, as monitored by different fluorescent membrane markers. Furthermore, ATP content of cryopreserved spermatozoa was significantly higher when PAF was used at a concentration of 1 × 10⁻³ M compared with the control and other PAF treatments, regardless of the incubation time. The findings of this study indicated that treatment with 1 × 10⁻³ M PAF at 120 min of incubation rendered better quality of cryopreserved canine semen, which was associated with improved sperm motility parameters and ATP content. It can be suggested that exogenous PAF addition is beneficial as a supplement for canine semen extender used for cryopreservation.
11
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Puerperal influence of bovine uterine health status on the mRNA expression of pro-inflammatory factors

72%
Peter S., Michel G., Hahn A., Ibrahim M., Lubke-Becker A., Jung M., Einspanier R., Gabler C.
Journal of Physiology and Pharmacology
|
2015
|
tom 66
|
nr 3
12
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

The role of platelet-activating factor (PAF) antagonists and nitric oxide in cardiac actions of PAF. Electrophysiological and morphological study

72%
Kecskemeti V., Balogh I.
Journal of Physiology and Pharmacology
|
2000
|
tom 51
|
nr 4,1
13

Age-dependent and seasonal changes in the activity of platelet-activating factor acetylhydrolase [PAF-AH] of boar seminal plasma in relation to the content of calcium ions

72%
Kordan W., Strzezek J., Fraser L., Soliwoda D.
Animal Science Papers and Reports
|
2003
|
tom 21
|
nr 1
The objective of this study was to determine the activity of platelet-activating factor acetylhydrolase (PAF-AH) and the content of calcium ions (Ca2+) of boar seminal plasma in relation to season and animal age. Wide fluctuations in PAF-AH activity and Ca2+ content of plasma were observed. PAF-AH activity ranged from 334.2 to 524.3 nmol PAF hydrolyzed/min/mg protein, whereas the Ca2+ content from 2.4 to 3.4 mg/100 ml. In some cases PAF-AH activity was positively correlated with Ca2+ content.Both the PAF-AH activity and Ca2+ content of plasma depended on the season and age of the boars.The age-related and seasonal changes observed in PAF-AH activity suggest that the enzyme may play a role in boar reproductive functions.
14
Content available remote

The platelet activating factor triggers preconditioning-like cardioprotective effect via mitochondrial K-ATP channels and redox-sensible signaling

72%
Penna C., Mognetti B., Tullio F., Gattullo D., Mancardi D., Pagliaro P., Alloatti G.
Journal of Physiology and Pharmacology
|
2008
|
tom 59
|
nr 1
Endogenous platelet activating factor (PAF) is involved in heart ischemic preconditioning. PAF can also afford pharmacological preconditioning. We studied whether mitochondrial-ATP-sensitive K+ (mKATP) channels and reactive oxygen species (ROS) are involved in PAF-induced cardioprotection. In Group 1 control hearts, Langendorff-perfused rat hearts underwent 30 min ischemia and 2 hours of reperfusion. Group 2 hearts, before ischemia, were perfused for 19 min with PAF (2x10-11 M); Groups 3 and 4 hearts were co-infused with PAF and N-acetyl-L-cysteine or 5-hydroxydecanoate to scavenge ROS or to block mKATP channels, respectively. Left ventricular pressure and infarct size were determined. PAF-pretreatment reduced infarct size (33 ± 4% vs 64 ± 4.6 % of the area at risk of control hearts) and improved pressure recovery. Infarct-sparing effect of PAF was abolished by N-acetyl-L-cysteine and 5-hydroxydecanoate. Thus, the cardioprotective effect exerted by PAF-pretreatment involves activation of mKATP channels and redox signaling in pre-ischemic phase.
15
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Helicobacter pylori stimulates gastric acid secretion via platelet activating factor

58%
Sobhani I., Bado A., Cherifi Y., Moizo L., Laigneau J. P., Pospai D., Mignon M., Lewin M. J.
Journal of Physiology and Pharmacology
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1996
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tom 47
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nr 1
16

Functions of platelet activating factor [PAF] in mammalian reproductive processes: a review

58%
Kordan W., Strzezek J., Fraser L.
Polish Journal of Veterinary Sciences
|
2003
|
tom 06
|
nr 1
Platelet activating factor, PAF, (l-0-alkyl-2-acetyl-sn-glycero3-phosphorylcholine) is a naturally occurring compound of membrane phospholipid. The aim of this article was to briefly review current research on the significant role of PAF in mammalian reproductive functions. The involvement of this phospholipid in the female reproductive processes may indicate that it plays an important role in ovarian follicular development, reproductive cycle and pregnancy. A full understanding of PAF functions in sperm motility, capacitation and the acrosome reaction is mandatory to correctly interpret its role in the male reproductive processes. This review also addressed the importance of the mechanism regulating PAF metabolism, PAF-acetylhydrolase (PAF-AH), during the membrane fusion events associated with fertilization.
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