OBJECTIVETo determine the expression of E-prostanoid1 (EP(1)) and F-prostanoid (FP) receptor mRNAs in iris-ciliary bodies of the human eye using in situ hybridization.

METHODSEP(1) and FP receptor mRNAs were detected by riboprobes labeled with digoxigenin on paraffin sections of the iris-ciliary body tissue of the human eye using in situ hybridization.

RESULTSEP(1) and FP receptor mRNAs were highly expressed in blood vessels, muscles and the endothelia of the iris. EP(1) receptor hybridization signals were present in all muscle fibers of the ciliary body. Hybridization signal corresponding to FP receptor mRNA transcript was predominantly expressed in the circular muscle and in the collagenous connective tissues of the ciliary body. FP receptor mRNA was not detected in radial and longitudinal muscles.

CONCLUSIONSEP(1) and FP receptor mRNAs in human ocular tissues appear to be widely localized in the functional sites of the respective receptor agonists. Selective localization of EP(1) and FP receptor mRNAs in the circular muscles and collagenous connective tissues of the ciliary body suggests that EP(1) and FP receptors play an important role in enhancing uveoscleral outflow of aqueous humor.

Ciliary Body ; metabolism ; Humans ; In Situ Hybridization ; Iris ; metabolism ; RNA, Messenger ; analysis ; Receptors, Prostaglandin ; genetics ; Receptors, Prostaglandin E ; genetics ; Receptors, Prostaglandin E, EP1 Subtype

OBJECTIVETo investigate the roles of thromboxane A(2) (TXA(2)) and prostaglandin I(2) (PGI(2)) in development of oligohydramnios.

METHODSThe concentration of TXB(2) and 6-keto-PGF1 in umbilical cord blood collected from 30 normal parturients (control) and 30 parturients with oligohydramnios was detected by radioimmunoassay to calculate the TXA(2)/PGI(2) ratio. Immunohistochemistry was performed to detect the contents of TXA(2)R in vascular endothelial cell in the placental villi.

RESULTSCompared with the control group, the concentration of umbilical cord blood TXB(2) in oligohydramnios group was significantly increased (P<0.01), but the elevation of 6-keto-PGF(2) concentration was not statistically significant (P>0.05). The oligohydramnios group showed significantly higher positivity rates of TXB2 and 6-keto-PGF1 in than the control group (P<0.01), and the positivity rate of TXA(2)R in the vascular endothelial cells in the placental villi was also significantly higher in the oligohydramnios group (22/30, 77.3% vs 11/30, 36.7%, P<0.05). Most of the TXA(2)R-positive cases in the oligohydramnios group showed strong positivities of TXA(2)R.

CONCLUSIONAbnormal elevation of TXA(2) concentration in the umbilical cord blood and the TXA(2)/PGI(2) imbalance are responsible for the development of oligohydramnios.

Adult ; Alprostadil ; analogs & derivatives ; blood ; Epoprostenol ; blood ; Female ; Fetal Blood ; chemistry ; Humans ; Oligohydramnios ; metabolism ; Placenta ; chemistry ; Pregnancy ; Radioimmunoassay ; Receptors, Thromboxane A2, Prostaglandin H2 ; chemistry ; Thromboxane A2 ; blood

BACKGROUND/AIMS: Lubiprostone, a chloride channel type 2 (ClC-2) activator, was thought to treat constipation by enhancing intestinal secretion. It has been associated with increased intestinal transit and delayed gastric emptying. Structurally similar to prostones with up to 54% prostaglandin E2 activity on prostaglandin E receptor 1 (EP1), lubiprostone may also exert EP1-mediated procontractile effect on intestinal smooth muscles. We investigated lubiprostone's effects on intestinal smooth muscle contractions and pyloric sphincter tone. METHODS: Isolated murine small intestinal (longitudinal and circular) and pyloric tissues were mounted in organ baths with modified Krebs solution for isometric recording. Basal muscle tension and response to electrical field stimulation (EFS; 2 ms pulses/10 V/6 Hz/30 sec train) were measured with lubiprostone (10(-10)-10(-5) M) +/- EP1 antagonist. Significance was established using Student t test and P < 0.05. RESULTS: Lubiprostone had no effect on the basal tension or EFS-induced contractions of longitudinal muscles. With circular muscles, lubiprostone caused a dose-dependent increase in EFS-induced contractions (2.11 +/- 0.88 to 4.43 +/- 1.38 N/g, P = 0.020) that was inhibited by pretreatment with EP1 antagonist (1.69 +/- 0.70 vs. 4.43 +/- 1.38 N/g, P = 0.030). Lubiprostone had no effect on circular muscle basal tension, but it induced a dose-dependent increase in pyloric basal tone (1.07 +/- 0.01 to 1.97 +/- 0.86 fold increase, P < 0.05) that was inhibited by EP1 antagonist. CONCLUSIONS: In mice, lubiprostone caused a dose-dependent and EP1-mediated increase in contractility of circular but not longitudinal small intestinal smooth muscles, and in basal tone of the pylorus. These findings suggest another mechanism for lubiprostone's observed clinical effects on gastrointestinal motility.
Alprostadil ; Animals ; Baths ; Chloride Channels ; Constipation ; Contracts ; Dinoprostone ; Gastric Emptying ; Gastrointestinal Motility ; Humans ; Intestinal Secretions ; Intestine, Small ; Isotonic Solutions ; Mice ; Muscle Tonus ; Muscle, Smooth ; Muscles ; Pylorus ; Receptors, Prostaglandin E ; Receptors, Prostaglandin E, EP1 Subtype ; Lubiprostone

OBJECTIVETo investigate the effect of prostaglandins E2 (PGE2) in enhancing vascular endothelial growth factor (VEGF) expression in a rat macrophage cell line and the effect of the media from PGE2-inuced rat macrophages on angiogenetic ability of human umbilical vein endothelial cells (HUVECs) in vitro.

METHODSWestern blotting and qPCR were employed to investigate the expressions of VEGF protein and mRNAs in rat macrophage cell line NR8383 stimulated by PGE2 in the presence or absence of EP2 receptor inhibitor (AH6809) and EP4 receptor inhibitor (AH23848). Conditioned supernatants were obtained from different NR8383 subsets to stimulate HUVECs, and the tube formation ability and migration of the HUVECs were assessed with Transwell assay.

RESULTSPGE2 stimulation significantly enhanced the expression of VEGF protein and mRNAs in NR8383 cells in a dose-dependent manner. The supernatants from NR8383 cells stimulated by PGE2 significantly enhanced tube formation ability of HUVECs (P<0.05) and promoted the cell migration. Such effects of PGE2 were blocked by the application of AH6809 and AH23848.

CONCLUSIONPGE2 can dose-dependently increase VEGF expression in NR8383 cells, and the supernatants derived from PGE2-stimulated NR8383 cells can induce HUVEC migration and accelerate the growth of tube like structures. PGE2 are essential to corpus luteum formation by stimulating macrophages to induce angiogenesis through EP2/EP4.

Animals ; Cell Line ; Cell Movement ; Cells, Cultured ; Culture Media, Conditioned ; pharmacology ; Dinoprostone ; pharmacology ; Human Umbilical Vein Endothelial Cells ; cytology ; drug effects ; Humans ; Macrophages ; chemistry ; Neovascularization, Pathologic ; RNA, Messenger ; Rats ; Receptors, Prostaglandin E, EP2 Subtype ; metabolism ; Receptors, Prostaglandin E, EP4 Subtype ; metabolism ; Vascular Endothelial Growth Factor A ; Xanthones ; pharmacology

OBJECTIVETo investigate the effect of Guizhi Tang and its active components on the fever induced by EP3 receptor agonist sulprostone in rats.

METHODThe rise in body temperature evoked by a LCV(lateral cerebroventricle)-injection of sulprostone was compared with that of sulprostone induced-fever rats pretreated with Guizgi Tang and its active compounds, cinnamaldehyde, cinnamic acid and total glucosides of paeony.

RESULTPretreatments with Guizhi Tang and cinnamaldehyde inhibited the rise in body temperature induced by sulprostone, while cinnamic acid tended to augment the fever. The sulprostone-induced fever was blocked by an ip pretreatment of total glucosides of paeony even below the basement.

CONCLUSIONPresent data suggest that interruption with the down-stream events of EP3 receptor may contribute to the antipyretic action of Guizhi Tang, cinnamaldehyde and the total glucosides of paeony, while cinnamic acid may have no such effect.

Acrolein ; analogs & derivatives ; isolation & purification ; pharmacology ; Analgesics, Non-Narcotic ; isolation & purification ; pharmacology ; Animals ; Body Temperature ; drug effects ; Cinnamates ; isolation & purification ; pharmacology ; Dinoprostone ; analogs & derivatives ; Drug Combinations ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Fever ; chemically induced ; physiopathology ; Glucosides ; isolation & purification ; pharmacology ; Male ; Paeonia ; chemistry ; Plants, Medicinal ; chemistry ; Rats ; Rats, Wistar ; Receptors, Prostaglandin E ; agonists ; Receptors, Prostaglandin E, EP3 Subtype

OBJECTIVETo investigate the changes of the activity of both protein kinase A and C and the mechanisms of antipyretic action of Guizhi decoction.

METHODThe fever responses were observed after combination injection of H-89 (a selective inhibitor of PKA) and calphostin C (a selective inhibitor of PKC), and oral pretreatment of Guizhi decoction in fever rats induced by an intra-cerebroventricular (icv) injection of an EP3 agonist, and both PKA and PKC activity in hypothalamus were measured in rats pretreated with Guizhi decoction and vehicle using isotopic tracing assay.

RESULTThe rise in rat body temperature was inhibited by H-89, Calphostin C, and Guizhi decoction, moreover, pretreatment with Guizhi decoction reduced PKA activity obviously. PKC activity in model rats exhibited a tendency to drop compared with that of control group, Oral administration of Guizhi decoction in large dose inhibited the response significantly, while the low dose of Guzhi decoction has no effect on PKC.

CONCLUSIONBoth PKA and PKC may participate in the mechanism of fever induction by EP3 agonist. The decrease of PKA and PKC may contribute to the antipyretic action of Guizhi decoction, some isoenzyme of PKC may play a role in the fever production.

Analgesics, Non-Narcotic ; pharmacology ; Animals ; Cinnamomum aromaticum ; chemistry ; Cyclic AMP-Dependent Protein Kinases ; metabolism ; Dinoprostone ; analogs & derivatives ; Dose-Response Relationship, Drug ; Drug Combinations ; Drugs, Chinese Herbal ; administration & dosage ; isolation & purification ; pharmacology ; Fever ; chemically induced ; enzymology ; Hypothalamus ; enzymology ; Male ; Plants, Medicinal ; chemistry ; Protein Kinase C ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Receptors, Prostaglandin E ; agonists ; Receptors, Prostaglandin E, EP3 Subtype

Several new antithrombotic drugs have been developed and approved to use in clinical practice recently. Dabigatran, a direct thrombin inhibitor, and rivaroxaban, a factor Xa inhibitor, have been approved in many countries including Korea to prevent stroke in patient with atrial fibrillation. Apixaban, another factor Xa inhibitor, showed good results in clinical trial and is waiting for approval for clinical use. New antiplatelet agent, terutroban, selective thromboxane A2 receptor inhibitor, failed to prove the efficacy over the aspirin in secondary stroke prevention. Vorapaxar, a new antiplatelet agent that inhibits thrombin through PAR-1 antagonism, showed a high incidence of intracranial hemorrhage in patient with a history of stroke.
Aspirin ; Atrial Fibrillation ; Benzimidazoles ; beta-Alanine ; Factor Xa ; Humans ; Incidence ; Intracranial Hemorrhages ; Korea ; Lactones ; Morpholines ; Naphthalenes ; Propionates ; Pyrazoles ; Pyridines ; Pyridones ; Receptors, Thromboxane A2, Prostaglandin H2 ; Stroke ; Thiophenes ; Thrombin ; Dabigatran ; Rivaroxaban

OBJECTIVETo provide more detailed information on the roles of lipid peroxidation in the pathogenesis of chronic pancreatic injuries in a pre-clinical rat model.

METHODSTotally 72 rats were divided into 6 groups (12 in each group) Rats in 5 experimental groups (n = 12) were fed with a high-fat diet (1% cholesterol, 10% lard, 0.3% sodium tauroglycocholate, 87.3% standard rodent chow as the control group) for 2, 4, 6, 10 and 16 weeks, respectively. Morphological studies in the pancreas tissue samples from rats were investigated by using various histological methods. Pancreatic stellate cells (PSCs) were identified by immunohistochemical staining for Desmin and α-smooth muscle actin (α-SMA). The expression of the lipid peroxidation was detected by immunostaining for 4-hydroxy-2-nonenal (4-HNE) and thromboxane A2 receptor (TxA2r). The co-localization of α-SMA and 4-HNE or α-SMA and TxA2r in PSCs was also analyzed in this study.

RESULTSPancreatic cells with positive staining for Desmin and α-SMA in HFD rats were distributed in a more extensive way when compared to that in the control group. The levels of pancreatic 4-HNE and TxA2r were increased in rats from HFD groups significantly. The co-localization of 4-HNE and TxA2r were also found within activated PSCs in both of groups.

CONCLUSIONThe results showed that a chronic HFD feeding may increase the lipid peroxidation process and collagen synthesis through a critical signaling pathway of activated PSCs following pancreatic injuries in rats.

Actins ; metabolism ; Aldehydes ; metabolism ; Animals ; Collagen ; biosynthesis ; Desmin ; metabolism ; Diet, High-Fat ; adverse effects ; Disease Models, Animal ; Lipid Peroxidation ; Male ; Oxidative Stress ; Pancreas ; metabolism ; pathology ; Pancreatic Diseases ; metabolism ; pathology ; Rats ; Rats, Sprague-Dawley ; Receptors, Thromboxane A2, Prostaglandin H2 ; metabolism

Adipose tissue is the energy storage organ of the body, and excess energy is stored in adipocytes in the form of lipid droplets. The homeostasis of adipose tissue is the basis for the body to maintain normal metabolic activity. Prostaglandin E (PGE) is an important lipid mediator in the body. It is synthesized in almost all tissues and participates in the regulation of many physiological processes such as blood pressure, glucose and lipid metabolism, and inflammation. PGE is abundant in white adipose tissue, where it is involved in the regulation of fat metabolism. PGE plays its biological role through binding to four G protein coupled receptors (prostaglandin E receptors), including EP-1, -2, -3, and -4. The EP4 subtype has been proved to play an important role in adipogenesis and adipose metabolism: it could inhibit adipogenesis while it was activated, whereas its knockout could promote lipolysis. This review summarized the relationship between EP4 and adipose metabolism, hoping to identify new targets of drug development for metabolic disorders.
Adipocytes ; Adipogenesis ; Adipose Tissue ; metabolism ; Humans ; Receptors, Prostaglandin E, EP4 Subtype ; physiology

Prostaglandin E2 (PGE2) is a cyclooxygenase metabolite of arachidonic acid. It acts as a bioactive lipid and plays an important role in regulating many biological processes. PGE2 binds to 4 different G protein-coupled receptors including prostaglandin E2 receptor subtypes EP1, EP2, EP3 and EP4. The EP4 receptor is widely expressed in most of human organs and tissues. Increasing evidence demonstrates that EP4 is essential for cardiovascular homeostasis and participates in the pathogenesis of many cardiovascular diseases. Here we summarize the role of EP4 in the regulation of cardiovascular function and discuss potential mechanisms by which EP4 is involved in the development of cardiovascular disorders with a focus on its effect on inflammation.
Cardiovascular Diseases ; physiopathology ; Cyclooxygenase 2 ; Dinoprostone ; physiology ; Humans ; Receptors, Prostaglandin E, EP4 Subtype ; physiology