Evaluation of real-life data on the use of inhaler devices, including satisfaction and adherence to treatment, by community pharmacists in partnership with pulmonary disease specialists.

OBJECTIVE: The use of inhaler device (UID) and the satisfaction and adherence of patients to treatment were evaluated by Istanbul city community pharmacists to obtain real-life data from patients with asthma or chronic obstructive pulmonary disease (COPD). METHODS: Pharmacists educated by pulmonary disease specialists asked patients who combined medications with inhaler devices to fill out a questionnaire prepared by the specialists. Each patient's UID was checked, and their errors were corrected by showing them the already prepared standard video of their inhaler device. Afterward, the UID was repeated and rechecked. The visual analog scale (VAS), feeling of satisfaction with the inhaler (FSI-10) questionnaire, and the Morisky Green Levine (MGL) scale were used for symptom control, satisfaction, and adherence, respectively. Then, we compared the results of three different types of inhalers: metered dose inhalers (MDI), dry powder inhalers (DPI), and dry powder inhalation capsules (DPI Caps). RESULTS: Twenty-seven (19.3%) patients used MDI, 42 (30%) used DPI caps, and 71 (50.7%) used DPI. UID before training was better in patients with DPI than in those with MDI and DPI Cap (p < 0.001). After training, the UID increased in all three groups (p < 0.001). The VAS scores were high in the DPI Caps group than the other groups (p < 0.001). The FSI-10 score was not significantly different among the groups (p > 0.05). Full-adherence was observed in 36.8% of the MDI group, 39.1% of the DPI Caps group, and 21.7% of the DPI groups (p > 0.05). CONCLUSION: The partnership between community pharmacists and pulmonary disease specialists improved patients' UID.

Hydrogen sulfide is synthesized endogenously in both retinal artery and retina mostly via CSE.

Hydrogen sulfide (H2S) is an important gasotransmitter expressed in various tissues of the organism, including the eye. It is known that H2S is localized especially in the retina and corneal layers in bovine eye. The enzymes that mediate H2S synthesis are 3-mercaptopyruvate sulfurtransferase (3-MST), cystathionine ß-synthase (CBS) and cystathionine γ-lyase (CSE). Herein, we aimed to investigate the concentration levels and distribution profiles of these enzymes in bovine retina and retinal artery. Enzyme levels were measured by ELISA and distribution were determined by immunofluorescence microscopic analysis. Much higher concentrations of CBS and CSE have been detected in the retinal artery compared to the retina. In both tissues, particulary 3-MST was found at the lowest level while, CSE was determined to be the most abundant enzyme among the others. CBS distribution was shown in both endothelial and smooth muscle layers, while CSE was seen especially in the endothelial layer of the retinal artery. In the retina, CBS and CSE were expressed in cone-basil cells and retinal ganglion cells, while CSE was also present in bipolar cells. Our results indicated that H2S is synthesized endogenously in ocular tissues. The widespread expression of H2S synthesizing enzymes in the retina and retinal artery of the bovine eye, which has anatomical similarities with the human eye, may suggest a protective role for H2S against retinal vascular diseases as well as a regulatory role in the retinal vascular tone.

In Vitro Effects of Eicosapentaenoic and Docosahexaenoic Acid on the Vascular Tone of a Human Saphenous Vein: Influence of Precontractile Agents.

BACKGROUND: Cardiovascular effects of omega-3 polyunsaturated fatty acids including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been widely reported. However, there are limited studies concerning their effects on human blood vessels. Therefore, the aim of this study was to investigate the direct vascular effects of EPA and DHA on the human saphenous vein (SV) precontracted with either prostaglandin F2α (PGF2α), or thromboxane A2 analogue (U46619), or norepinephrine (NE). Moreover, we aimed to investigate the protein expression of free fatty acid receptor 4 (FFAR4) in human SV. METHODS: Pretreatment of human SV rings with EPA and DHA (100 µM, 30 min) was tested on vascular reactivity induced by PGF2α (10 nM to 5 µM), NE (10 nM to 100 µM), and U46619 (1 nM to 100 nM). In addition, direct relaxant effects of EPA/DHA (1-100 µM) were tested in human SV rings precontracted by PGF2α, NE, and U46619. Furthermore, the involvement of potassium channels on their vascular effects was investigated in the presence of the nonselective K+ channel inhibitor tetraethylammonium chloride. RESULTS: Pretreatment with EPA and DHA resulted in a significant decrease in vascular reactivity induced by U46619 and PGF2α compared to NE. In the presence of TEA, the relaxant effects of EPA and DHA were significantly decreased in SV preparations precontracted by U46619 and PGF2α for DHA. Furthermore, FFAR-4 protein was expressed in tissue extracts of human SV. CONCLUSIONS: Our study demonstrates that both EPA and DHA reduce the increased vascular tone elicited by contractile agents on the human SV and that the direct vasorelaxant effect is likely to involve potassium channels.

Resveratrol ameliorates the cyclosporine-induced vascular and renal impairments: possible impact of the modulation of renin-angiotensin system.

Cyclosporine, an immunosuppressive drug, exhibits a toxic effect on renal and vascular systems. The present study investigated whether resveratrol treatment alleviates renal and vascular injury induced by cyclosporine. Cyclosporine (25 mg/kg per day, s.c.) was given for 7 days to rats either alone or in combination with resveratrol (10 mg/kg per day, i.p.). Relaxation and contraction responses of aorta were examined. Serum levels of blood urea nitrogen, creatinine, angiotensin II, and angiotensin 1-7 were measured. Histopathological examinations as well as immunostaining for 4-hydroxynonenal and nitrotyrosine were performed in the kidney. RNA expressions of renin-angiotensin system components were also measured in renal and aortic tissues. Cyclosporine decreased the endothelium-dependent relaxation and increased vascular contraction in the aorta. It caused renal tubular degeneration and increased immunostaining for 4-hydroxynonenal, an oxidative stress marker. Cyclosporine also caused upregulations of the vasoconstrictive renin-angiotensin system components in renal (angiotensin-converting enzyme) and aortic (angiotensin II type 1 receptor) tissues. Resveratrol co-treatment prevented the cyclosporine-related deteriorations. Moreover, it induced the expressions of vasodilatory effective angiotensin-converting enzyme 2 and angiotensin II type 2 receptor in aorta and kidney, respectively. We conclude that resveratrol may be effective in preventing cyclosporine-induced renal tubular degeneration and vascular dysfunction at least in part by modulating the renin-angiotensin system.

Relaxant effect of atorvastatin on isolated rat gastric fundus strips: implications for Ca2+-signalling mechanisms.

Statins are determined to have various pleiotropic effects apart from their lipid-lowering properties. Herein, we investigated the direct effects of atorvastatin on gastric smooth muscle tone. Atorvastatin effectively relaxed isolated rat gastric fundus strips precontracted with acetylcholine, potassium chloride, and serotonin. Incubation of the strips with nitric oxide synthase inhibitor, l-NOARG (10-4 M, 20 min), l-type voltage-operated Ca2+ channel (VOCC) blocker, nifedipine (10-6 M, 30 min), KATP channel blocker, glibenclamide (10-5 M, 30 min), or precursor of cholesterol, mevalonate (10-2 M, 45 min) did not change the relaxations to atorvastatin. However, pretreatment of fundus strips with atorvastatin (3×10-5-3×10-4 M, 30 min) inhibited the contractions to calcium chloride (10-4-10-1 M), acetylcholine (10-4 M), and caffeine (20 mM) in the calcium-free medium. Moreover, atorvastatin reduced the contractions induced by sarco-endoplasmic reticulum Ca2+-ATPase (SERCA) inhibitor, cyclopiazonic acid (10-7-3×10-5 M). The current study demonstrated that atorvastatin produces an acute relaxant effect on gastric fundus strips, which appears to be mediated by several Ca2+-signalling mechanisms such as the blockade of l-type VOCC-independent Ca2+ entry, decrease in smooth muscle Ca2+ sensitivity, inhibition of IP3- and ryanodine-sensitive intracellular stores to mediate Ca2+ release, as well as the activation of SERCA. This acute relaxing effect seems unlikely to be related with nitric oxide, KATP channels, and the mevalonate pathway.

Relaxant effect of the prostacyclin analogue iloprost on isolated human radial artery: An approach for the reversal of graft spasm.

Radial artery graft spasm in the perioperative or postoperative period of coronary bypass surgery necessitates urgent treatment due to risk of graft failure and mortality. Herein, we evaluated the effect of iloprost, a prostacyclin (PGI2) analogue, against the contractions produced by noradrenaline and potassium chloride on isolated human radial artery. Following the determination of endothelial and vascular relaxing capacities of the arteries, iloprost (10-9M-10-6M) was cumulatively applied on rings precontracted submaximally with the spasmogens. In some rings, the response to iloprost was assessed following pretreatment with nitric oxide (NO) synthase inhibitor, l-NAME (3×10-4M,30min). Iloprost produced complete relaxations on radial artery rings precontracted with noradrenaline whereas, only moderate relaxations against the contractions induced by potassium chloride. Notably, the relaxation to iloprost was remarkably blunted in radial arteries with impaired endothelial function. Moreover, the relaxation to iloprost was unchanged in rings pretreated with l-NAME. Our results demonstrated that iloprost could be a potent relaxant agent in reversing radial artery spasm, particularly initiated by noradrenaline, possibly acting via an endothelium-mediated mechanism unrelated to NO.

Omega-3 polyunsaturated fatty acids reduce vascular tone and inflammation in human saphenous vein.

Dietary intake of omega-3 polyunsaturated fatty acids, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), has been reported to have beneficial cardiovascular effects. However, little is known about the effect of EPA and DHA on human vascular tone. Therefore, the aim of this study is to evaluate the effect of EPA and DHA on vascular tone of the human saphenous vein (SV) obtained from patients undergoing coronary bypass operation under normal and inflammatory conditions. Moreover, we aimed to investigate the effect of EPA and DHA on the release of inflammatory mediators from SV. Pretreatment of SV with EPA and DHA (100µM, 18h) decreased the contractile response of SV to norepinephrine (NE) under normal and inflammatory conditions. Moreover, EPA and DHA pretreatment diminished increased Monocyte Chemoattractant Protein-1 (MCP-1) and Tumor Necrosis Factor-alpha (TNF-α) release from SV under inflammatory conditions. In conclusion, our results suggest that EPA and DHA pretreatment may be beneficial to counteract graft vasospasm and vascular inflammation in SV which are important factors in graft failure development. Therefore, dietary intake of EPA and DHA may have potential clinical applications in improving coronary bypass graft patency.

Inhibition of microsomal PGE synthase-1 reduces human vascular tone by increasing PGI2 : a safer alternative to COX-2 inhibition.

BACKGROUND AND PURPOSE: The side effects of cyclooxygenase-2 (COX-2) inhibitors on the cardiovascular system could be associated with reduced prostaglandin (PG)I2 synthesis. Microsomal PGE synthase-1 (mPGES-1) catalyses the formation of PGE2 from COX-derived PGH2 . This enzyme is induced under inflammatory conditions and constitutes an attractive target for novel anti-inflammatory drugs. However, it is not known whether mPGES-1 inhibitors could be devoid of cardiovascular side effects. The aim of this study was to compare, in vitro, the effects of mPGES-1 and COX-2 inhibitors on vascular tone in human blood vessels. EXPERIMENTAL APPROACH: The vascular tone and prostanoid release from internal mammary artery (IMA) and saphenous vein (SV) incubated for 30 min with inhibitors of mPGES-1 or COX-2 were investigated under normal and inflammatory conditions. KEY RESULTS: In inflammatory conditions, mPGES-1 and COX-2 proteins were more expressed, and increased levels of PGE2 and PGI2 were released. COX-2 and NOS inhibitors increased noradrenaline induced vascular contractions in IMA under inflammatory conditions while no effect was observed in SV. Interestingly, the mPGES-1 inhibitor significantly reduced (30-40%) noradrenaline-induced contractions in both vessels. This effect was reversed by an IP (PGI2 receptor) antagonist but not modified by NOS inhibition. Moreover, PGI2 release was increased with the mPGES-1 inhibitor and decreased with the COX-2 inhibitor, while both inhibitors reduced PGE2 release. CONCLUSIONS AND IMPLICATIONS: In contrast to COX-2 inhibition, inhibition of mPGES-1 reduced vasoconstriction by increasing PGI2 synthesis. Targeting mPGES-1 could provide a lower risk of cardiovascular side effects, compared with those of the COX-2 inhibitors. LINKED ARTICLES: This article is part of a themed section on Targeting Inflammation to Reduce Cardiovascular Disease Risk. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.22/issuetoc and http://onlinelibrary.wiley.com/doi/10.1111/bcp.v82.4/issuetoc.

Vascular function and arginine and dimethylarginines in gentamicin-induced renal failure: a possible effect of heme oxygenase 1 inducer hemin.

Increased oxidative stress and disturbance in nitric oxide bioavailability lead to endothelial dysfunction and cardiovascular complication in renal disease. Gentamicin (GM), a commonly used antibiotic, exhibits a toxic effect on renal proximal tubules. Prevention of its nephrotoxicity is important. Therefore, we investigated whether heme oxygenase 1 HO-1) induction influenced kidney and vascular function in GM-administered rats. GM (100 mg·kg-1·day-1; i.p.) was given to rats alone or together with hemin (20 mg·kg-1 on alternate days; i.p.) for 14 days. Plasma and kidney l-arginine, asymmetric dimethylarginine (ADMA), and symmetric dimethylarginine (SDMA) as well as kidney 4-hydroxynonenal (HNE) levels and myeloperoxidase (MPO) activity were measured. Histopathological examinations of kidney and relaxation and contraction responses of aorta were also examined. GM increased serum SDMA, urea nitrogen (BUN), and creatinine levels and caused histopathological alterations in the kidney. GM elevated HO-1 protein and mRNA expressions, 4-HNE level, and MPO activity and decreased antioxidant enzyme activities and l-arginine levels in the kidney. Decreased relaxation and contraction were detected in the aorta. Hemin restored renal oxidative stress and inflammatory changes together with vascular dysfunction, but did not affect SDMA, BUN, or creatinine levels. We conclude that HO-1 induction may be effective in improving renal oxidative stress, inflammation, and vascular dysfunction mediated by GM.

The elevation of intraocular pressure is associated with apoptosis and increased immunoreactivity for nitric oxide synthase in rat retina whereas the effectiveness of retina derived relaxing factor is unaffected.

Glaucoma is a progressive ocular disease that stands in the upper rank for the cause of blindness in worldwide. In the present study, we aimed to elucidate the possible disturbances occurred in the layers of retina due to an increase in intraocular pressure (IOP) and to verify the effectiveness of retina derived relaxing factor, i.e., RRF in this pathologic condition. The increase in IOP was induced by cauterization of the three of episcleral veins simultaneously in rats. After 8 weeks period, the retinas excised from the vein cauterized eyes were evaluated for the possible histopathological and ultrastructural alterations as well as for the relaxing effects on isolated bovine retinal and rat mesenteric arteries, in comparison with the retinas obtained from contralateral sham-operated eyes. In the retinas of IOP-elevated eyes, profound morphological deteriorations were determined in the ganglion and outer nuclear cell layers which were associated with an increased number of TUNEL positive cells in the ganglion and inner nuclear cell layers. Increased immunohistochemical stainings for three isoforms of nitric oxide synthase (NOS) were defined in almost all layers of the retinas of IOP-elevated eyes, in which eNOS was abundant particularly in the inner plexiform and ganglion cell layers. An irregular basal folding of retinal pigment epithelium (RPE) and an increased inter lamellar space of photoreceptor cell layer furtherly characterized the prominent degeneration of those layers in the retinas of IOP-elevated eyes. On the other hand, the relaxing effects of the retina obtained from IOP-elevated eyes were determined to be unchanged on the retinal and mesenteric arteries precontracted either with prostaglandin F2α (PGF2α, 30 µM) or potassium chloride (K(+), 100 mM), when compared with the relaxations of control retina obtained from contralateral sham-operated eyes. Overall, these findings suggested that the elevation of IOP induces prominent structural changes in rat retina particularly in the ganglion and inner layers that is associated with marked apoptosis and increased immunoreactivity for NOS, while the functional effectiveness of retina derived relaxing factor, i.e., RRF is unaffected.

Barnidipine ameliorates the vascular and renal injury in L-NAME-induced hypertensive rats.

The present study was aimed to investigate the influence of Barnidipine treatment on early stage hypertension by determining the function and morphology of the mesenteric and renal arteries as well as the kidney in N(ω)-Nitro-L-Arginine Methyl Ester (L-NAME)-induced hypertensive rats. Barnidipine (3 mg/kg/day p.o) was applied to rats after 2 weeks of L-NAME (60 mg/kg/day) administration, and continued for the next 3 weeks concomitantly with L-NAME. The systolic blood pressure (SBP) of rats was determined to decrease significantly in Barnidipine treated hypertensive group when compared to that of rats received L-NAME alone. Myograph studies demonstrated that the contractile reactivity to noradrenaline were significantly reduced in both of the resistance arteries while endothelium-dependent relaxations to acethylcholine were significantly diminished particularly in the mesenteric arteries of L-NAME-induced hypertensive rats. The impaired contractile and endothelial responses were completely restored by concomitant treatment of Barnidipine with L-NAME. Histopathological examinations verified structural alterations in the arteries as well as the kidney. Moreover, a decrease in endothelial nitric oxide synthase (eNOS) expression was presented both in the arteries and kidney of hypertensive rats which were increased following Barnidipine treatment. Elevated plasma levels of malondialdehyde (MDA) and myeloperoxidase (MPO) were also reduced in Barnidipine treated hypertensive rats. In conclusion, besides to its efficacy in reducing the elevated SBP, amelioration of vascular function, modulation of arterial and renal eNOS expressions as well as reduction of the plasma levels of oxidative and inflammatory biomarkers are possible supportive mechanisms mediating the favorable implications of Barnidipine in L-NAME-induced hypertension model.

Retina derived relaxation is mediated by K(ir) channels and the inhibition of Ca(2+) sensitization in isolated bovine retinal arteries.

Retinal relaxing factor (RRF) has recently been identified as a novel paracrine regulator of retinal circulation acting differently from well known mediators of the endothelium and the retina. Herein, we aimed to characterize the relaxing mechanism of the retina, i.e. RRF, by evaluating the role of Ca(+2)-dependent and -independent signaling mechanisms as well as inward rectifier K(+) (Kir) channels. Retinal relaxation was determined by placing a piece of retinal tissue just on top of the precontracted bovine retinal arteries mounted in a wire myograph. The retina produced a complete relaxation response, which display a biphasic character, in depolarized arteries contracted by L-type Ca(2+) channel agonist, Bay k 8644. Blockade of L-type Ca(2+) channel by nifedipine, inhibition of sarcoplasmic reticulum Ca(2+)-ATPase by cyclopiazonic acid or removal of extracellular Ca(2+) did not influence the prominent relaxation to the retina. Originally, retinal relaxation was found to be unaffected from the inhibition of myosin light chain kinase by ML7, whereas, completely abolished in the presence of myosin light chain phosphatase (MLCP) inhibitor, Calyculin A. Moreover, the inhibition of Rho kinase by its putative inhibitor, Y-27632 displayed comparable relaxant effects to RRF in retinal arteries precontracted either by prostaglandin F2α or K(+), and augmented the moderate response to the retina in K(+) precontracted arteries. In addition, retinal relaxation was significantly inhibited and lost its biphasic character in the presence of Kir channel blocker, Ba(2+). Our results suggested that inhibition of Ca(2+) sensitization through the activation of MLCP, possibly via interfering with Rho kinase, and the opening of Kir channels are likely to be involved in the inhibitory influence of RRF on the retinal arteries.

Control of human vascular tone by prostanoids derived from perivascular adipose tissue.

Perivascular adipose tissue (PVAT) surrounds most vessels and has now been recognized as a regulator of vascular functions. This effect of PVAT has been mostly demonstrated in vessels obtained from rats and mice. Thus, the aim of this study was to investigate anti-contractile effect of PVAT surrounding human coronary bypass grafts such as saphenous vein (SV) and internal mammary artery (IMA). Moreover, we aimed to determine the involvement of prostanoids in the anticontractile effect of PVAT. Human SV and IMA preparations were set up in an organ bath. The presence of PVAT in SV and IMA preparations significantly attenuated the contractile response to noradrenaline (NA). Preincubation with indomethacin, a cyclooxygenase inhibitor, increased NA contraction in SV preparations with PVAT. This effect was not observed in IMA preparation with PVAT incubated with indomethacin. The lower measurements of prostaglandin E2 (PGE2) released from PVAT surrounding IMA versus SV supported these effects. In conclusion, our results show that PVAT of SV could attenuate NA-induced contraction by releasing both PGE2 and prostacyclin (PGI2). In contrast to SV, PVAT of IMA exerts its anti-contractile effect independently from prostanoids. These observations suggest that retaining PVAT in human SV and IMA preparations may have potential clinical implications to improve coronary bypass graft patency.

Effects of Crataegus microphylla on vascular dysfunction in streptozotocin-induced diabetic rats.

Vascular dysfunction plays a key role in the pathogenesis of diabetic vascular disease. In this study, we aimed to investigate whether chronic in vivo treatment of Crataegus microphylla (CM) extract in diabetic rats induced with streptozotocin (STZ, intraperitoneal, 65 mg/kg) preserves vascular function and to evaluate whether the reduction of inducible nitric oxide synthase (iNOS), proinflammatory cytokines, and lipid peroxidation mediates its mechanisms of action. Starting at 4 weeks of diabetes, CM extract (100 mg/kg) was administrated to diabetic rats for 4 weeks. In aortic rings, relaxation to acetylcholine and vasoreactivity to noradrenaline were impaired, whereas aortic iNOS expression and plasma tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), total nitrite-nitrate, and malondialdehite levels were increased in diabetic rats compared with controls. Chronic CM treatment significantly corrected all the above abnormalities in diabetic rats. In comparison, pretreatment of the aorta of diabetic rats with N-[3(aminomethyl) benzyl]-acetamidine, dihydrochloride (10(-5) M), a selective inhibitor of iNOS, produced a similar recovery in vascular reactivity. These results suggest that chronic in vivo treatment of CM preserves endothelium-dependent relaxation and vascular contraction in STZ-induced diabetes, possibly by reducing iNOS expression in the aorta and by decreasing plasma levels of TNF-α and IL-6 and by preventing lipid peroxidation.

Retina evokes biphasic relaxations in retinal artery unrelated to endothelium, K(V), K(ATP), K(Ca) channels and methyl palmitate.

Retinal relaxing factor (RRF) is suggested to be released from the retina and to contribute in the maintenance of retinal arterial tone. Herein, we aimed to clarify the effects of retinal tissue in isolated bovine retinal arteries in comparison with choroidal tissue and to evaluate the possible role of endothelium and potassium channels. In parallel, the effects of palmitic acid methyl ester (PAME), a putative vasodilator proposed to be released from the retina, was also examined. A piece of bovine retinal or choroidal tissue was placed within a close proximity on top of retinal arteries mounted in a wire myograph and precontracted with noradrenaline, prostaglandin F(2α), endothelin-1, thromboxane A(2) mimetic, U46619 or potassium (K(+)). To elucidate possible mechanisms in the effects of retinal tissue, retinal arteries were either deendothelized or incubated with inhibitors of endothelial vasodilators, i.e. nitric oxide (NO) and prostaglandins, or K(+) channels. Unlike the choroid, retinal tissue produced rapid, biphasic and complete relaxations in isolated bovine retinal arteries precontracted with various spasmogens acting on distinct receptors. Endothelium removal or preincubation of retinal arteries with inhibitors of NO synthase; L-NOARG (10(-4)M), guanylate cyclase; ODQ (10(-5)M) and cyclooxygenase; indomethacin (10(-5)M), did not cause a significant difference in the relaxation profile. Additionally, retinal relaxations remained unchanged in the presence of respective inhibitors of ATP-sensitive (K(ATP)) (glibenclamide, 10(-5)M), voltage-dependent (K(V)) (4-aminopyridine, 2×10(-3)M), and calcium-activated (K(Ca)) (tetraethylammonium 10mM; charybdotoxin, 10(-7)M; and apamin, 5×10(-7)M) K(+) channels. Thus, our results provide novel evidence regarding the biphasic relaxing profile of RRF in the retinal artery which was unrelated to endothelium and K(+) channels (K(ATP), K(V) and K(Ca)). Interestingly, PAME (10(-14)-10(-5)M) did not provoke a relaxation in bovine retinal artery suggesting no association with RRF.

Involvement of prostaglandin F2α in preeclamptic human umbilical vein vasospasm: a role of prostaglandin F and thromboxane A2 receptors.

OBJECTIVE: Preeclampsia is characterized by hypertension and proteinuria developing after 20 weeks of gestation. Increased vasoconstriction can be one of the major underlying pathophysiological event in this syndrome. We examined the role of vasoconstrictor prostanoid, prostaglandin F2α (PGF2α) in preeclamptic and normotensive human umbilical veins. METHODS: Umbilical veins were set up in organ bath. The concentration-response curves of PGF2α (endogenous agonist of prostaglandin F receptor) and fluprostenol (prostaglandin F receptor selective agonist) were determined in normal and preeclamptic veins either in the absence or presence of BAY u3405 (thromboxane A2 receptor selective antagonist). PGF2α and its major metabolite concentrations were measured by enzyme immunoassay kit. The expression of vasoconstrictor prostanoid receptors was determined by western blot. RESULTS: The concentration-dependent contractions to PGF2α and fluprostenol were significantly increased in umbilical vein preparations derived from preeclamptic women compared with those of normotensives. Increased reactivity was related with enhanced sensitivity to these spasmogens in preeclamptic veins. BAY u3405 (10 µmol/l) did not modify the responsiveness to PGF2α in normal umbilical veins whereas moderately reduced the contractions in preeclamptic preparations. Serum concentrations of PGF2α and its major metabolite, 13,14-dihydro-15-keto-PGF2α, were comparable between preeclamptics and normotensives whereas the metabolite concentration was elevated in umbilical cord serum of preeclamptics. 13,14-dihydro-15-keto-PGF2α, release was also increased in umbilical vein preparations of preeclamptic women. An increased prostaglandin F receptor protein expression was determined whereas EP3 and thromboxane A2 protein expressions were unchanged in preeclamptic umbilical veins. CONCLUSION: Prostaglandin F and thromboxane A2 receptors activation by PGF2α could be involved in umbilical vasospasm observed in preeclampsia.

Matrix-type transdermal patches of verapamil hydrochloride: in vitro permeation studies through excised rat skin and pharmacodynamic evaluation in rats.

The objectives of this study were to develop matrix-type transdermal patches of verapamil hydrochloride (VRP) with pectin as a matrix polymer to investigate the influence of several terpenes on in vitro permeation of VRP through rat skin and to evaluate pharmacodynamic activity of transdermal formulations in rats. Matrix-type transdermal patches containing VRP were prepared using pectin as a matrix agent and propylene glycol as a plasticizer agent. Terpenes such as nerolidol, d-limonene, eucalpytol, menthone, and menthol were also used as a chemical enhancer to improve the skin penetration of VRP. The permeation studies were performed using Franz-type diffusion cells and full-thickness excised abdominal rat skin. Effects of terpenes on the permeation parameters of VRP were evaluated. In vitro skin permeation studies showed that nerolidol was the most promising enhancer among the enhancers examined in the present study, followed by d-limonene. Pharmacodynamic activity of the transdermal patches containing nerolidol or d-limonene was evaluated in rats by the measurement of systolic blood pressure for 360 min with the use of the tail cuff method. VRP transdermal patches significantly decreased the systolic blood pressure after 30 min and transdermal patches containing nerolidol and d-limonene maintained the decrease in blood pressure during the observation of 360 min.

Comparative effects of tolazoline and nitroprusside on human isolated radial artery.

BACKGROUND: The radial artery is increasingly being used in coronary revascularization as an alternative conduit to a saphenous vein graft. Its perfect endothelial capacity provides a high patency rate comparable with the internal mammary artery (IMA). However, its spastic characteristics cause difficulties during its intraoperative preparation and may lead to early postoperative graft failure. Thus, treatment and/or prevention of radial artery spasm with an effective vasodilator agent is essential for its longevity. Endogenous vasoconstrictors, including noradrenaline, endothelin-1, and thromboxane A2, are likely to play a role in the pathogenesis of graft spasm. In the present study, we evaluated the vasorelaxant effect of tolazoline, a nonselective alpha-adrenoceptor blocker, against the contractions induced by various spasmogenic agents in an isolated human radial artery. METHODS: Tolazoline (10(-9)-10(-4) M) or sodium nitroprusside (SNP, 10(-9)-10(-4) M) were cumulatively applied on radial artery rings precontracted submaximally with noradrenaline, endothelin-1, thromboxane analogue, U46619, or potassium chloride. In addition, some rings were pretreated with tolazoline (4 x 10(-6) M) for 30 minutes and the contractile response curve to noradrenaline was assessed in its presence. RESULTS: Tolazoline effectively reversed noradrenaline-induced contractions in the radial artery, whereas it failed to produce remarkable relaxations on rings contracted with other spasmogenic agents, while SNP overcame the contractions induced by all spasmogens to a similar extent. In addition, brief pretreatment of radial artery rings with tolazoline significantly inhibited the contractions to noradrenaline. CONCLUSIONS: Tolazoline is not as broadly effective as SNP against all spasmogens investigated; however, it may be effective in counteracting alpha-adrenoceptor-mediated vasospasm in human radial arteries.

The comparison of the relaxant effects of two methoxylated flavones in rat aortic rings.

The vascular effect of salvigenin (6-hydroxyapigenin 6,7,4' -trimethyl ether), a natural flavone, was investigated in comparison with another flavone, 6-hydroxyluteolin 6,7,3',4' -tetramethyl ether in rat aortic rings. Cumulative addition of their increasing concentrations (10(-9)-10(-4)M) produced graded relaxations on rings precontracted with noradrenaline (10(-6) M) and KCl (40 mM). The maximal relaxations induced by flavones were similar, however, based on their pEC50 values salvigenin displayed a higher potency than 6-hydroxyluteolin 6,7,3',4'-tetramethyl ether. Endothelium removal markedly reduced the relaxations to salvigenin while the responses to 6-hydroxyluteolin 6,7,3',4'-tetramethyl ether were partially affected. In addition, a significant decrease was observed in maximal responsiveness and sensitivity to flavones in the presence of L-NOARG, a NO synthase inhibitor. The cyclooxygenase inhibitor indomethacin significantly inhibited the relaxations to salvigenin, but not altered the responses to 6-hydroxyluteolin 6,7,3',4'-tetramethyl ether. Our results provide evidence that salvigenin is an effective flavone in causing vasorelaxation which appears to be mediated by endothelium derived NO and prostacyclin. Whereas, the other flavone, 6-hydroxyluteolin 6,7,3',4'-tetramethyl ether induced relaxant responses are partially endothelium, presumably NO mediated.