Abstract:
:Isolated perfused rat kidney was used to examine the possible mechanisms involved in the hypotensive/vasodilator actions of cryptolepine. In kidneys preconstricted by phenylephrine (PE 5-7.5 x 10(-7) M), cryptolepine at bolus doses of 2.5, 5, and 10 micrograms elicited dose-dependent reductions in perfusion pressure by 29.8 +/- 4.1, 43.3 +/- 3.9, and 54.3 +/- 4.9 mm Hg, respectively. In the presence of indomethacin, cryptolepine-induced reduction in perfusion pressure was not significantly changed, suggesting a lack of a cyclooxygenase-mediated component in its renal vasodilator response. Removal of the endothelium with p-bromophenacyl bromide (p-BPB 10 microM) inhibited the vasodilator response to cryptolepine 2.5, 5, and 10 micrograms to 10.2 +/- 1.8, 15.9 +/- 1.5, and 20.2 +/- 2.0 mm Hg, respectively (p < 0.01). The vasodilator response to acetylcholine (ACh 50 ng) was also reduced from a control value of 56.7 +/- 4.5 to 15.3 +/- 1.9 mm Hg (p < 0.01); responses to sodium nitroprusside (SNP 5 micrograms) and isoprenaline (1 microgram) were not affected. In kidneys treated with hydroquinone (10(-5) and 10(-4) M), a specific inhibitor of endothelium-dependent vasodilation, cryptolepine- and ACh-induced vasodilation were inhibited dose dependently (p < 0.01). N omega-nitro-L-arginine (L-NNA 10(-5)-10(-4) M), a specific inhibitor of the synthesis/release of endothelium-derived relaxing factor/nitric oxide (EDRF/NO), attenuated the vasodilator response to cryptolepine and ACh (50 ng) dose dependently. At 10(-4) M L-NNA, cryptolepine-induced vasodilation was reduced to 6.6 +/- 2.2 (2.5 micrograms), 10.9 +/- 2.2 (5 micrograms), and 13.3 +/- 1.4 mm Hg (10 micrograms). L-Arginine (10(-4) and 3 x 10(-4) M) but not D-arginine (10(-4) M) inhibited the effects of L-NNA, with vasodilatory effects of cryptolepine returning to control values, suggesting that the vasodilator material released by cryptolepine is EDRF, possibly NO. Methylene blue (MB 10(-4) M), the inhibitor of soluble guanylate cyclase which inhibited 50 ng ACh and 5 micrograms SNP-induced vasodilation also reduced the vasodilatory responses to cryptolepine to 0.8 +/- 0.8 (2.5 micrograms), 4.2 +/- 4.2 (5 micrograms), and 10.8 +/- 6.2 mm Hg (10 micrograms) suggesting that the effector pathway for cryptolepine-induced vasodilation is soluble guanylate cyclase-linked increase in cyclic GMP of vascular smooth muscle.
journal_name
J Cardiovasc Pharmacoljournal_title
Journal of cardiovascular pharmacologyauthors
Oyekan AOdoi
10.1097/00005344-199404000-00012subject
Has Abstractpub_date
1994-04-01 00:00:00pages
602-11issue
4eissn
0160-2446issn
1533-4023journal_volume
23pub_type
杂志文章abstract::Because the role of sodium channels in the initiation and maintenance of VF is not fully elucidated, we studied the significance of sodium channel activity in VF using sodium channel blockers. In nonischemic isolated feline hearts, the following electrophysiologic parameters were measured before and after application ...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/00005344-200012000-00015
更新日期:2000-12-01 00:00:00
abstract::Sinoaortic deafferentation (SAD) is characterized by arterial pressure lability, without sustained hypertension. Although SAD rats did not become hypertensive, their isolated aortas exhibit RCs. We have investigated whether these RCs are influenced by endothelium. Aortic rings were placed in an organ chamber, and the ...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/FJC.0b013e31813c112f
更新日期:2007-11-01 00:00:00
abstract::The binding of [3H]ketanserin and [125I]BE 2254 [( beta-(4-hydroxyphenyl)ethylaminomethyl]tetralone) was characterized in human brain cortex membranes. As observed in saturation experiments, [3H]ketanserin (a reportedly selective serotonin 5-HT2 ligand) and [125I]BE 2254 (a selective alpha 1-adrenergic antagonists) la...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:
更新日期:1987-01-01 00:00:00
abstract::Cardiovascular effects of Nifekalant were examined using halothane-anesthetized dogs, and its proarrhythmic potential was estimated with chronic complete atrioventricular block dogs. Nifekalant was intravenously administered to the halothane-anesthetized dogs in three doses of 0.03, 0.3, and 3 mg/kg/10 minutes with a ...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/00005344-200405000-00015
更新日期:2004-05-01 00:00:00
abstract::In this retrospective study, a group of 435 patients provided meaningful analyses of blood pressure and dosage data for treatment periods of up to 4.5 years. The protocol, study objectives, and pretreatment demographic characteristics of the group are summarized in this report, which is the first in a series in this i...
journal_title:Journal of cardiovascular pharmacology
pub_type: 临床试验,杂志文章
doi:
更新日期:1981-01-01 00:00:00
abstract::The vulnerable period (VP) is an interval of time during the cardiac cycle within which premature stimulation may lead to trains of responses (one: many stimulus-response coupling). Although the VP parallels the recovery of sodium channel availability, modulators of its boundaries remain unclear. Numerical studies of ...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:
更新日期:1992-05-01 00:00:00
abstract::Previous animal experiments suggest that the increase in the amplitude from the R-wave to the S-wave (RSh) may be more sensitive than other ECG measures to sodium channel blocking drug actions. We measured RSh of three orthogonal leads at baseline and during intravenous pharmacologic stimulation with adenosine, ajmali...
journal_title:Journal of cardiovascular pharmacology
pub_type: 临床试验,杂志文章
doi:10.1097/00005344-199510000-00023
更新日期:1995-10-01 00:00:00
abstract::Sarcosyl1, cysteinyl-S-methyl8-angiotensin II [(Sar1, Cys-Me8) Ang II] was examined for antagonism of angiotensin (Ang) responses in isolated rabbit atrial and aortic tissues. (Sar1, Cys-Me8) Ang II competitively antagonized Ang II responses in aorta at a concentration of 5 nM. Concentrations of the antagonist greater...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/00005344-198311000-00017
更新日期:1983-11-01 00:00:00
abstract::Endothelin-1 (ET-1) is a potent vasoconstrictive peptide produced by endothelial cells of blood vessels. This peptide has quite a unique structure and pharmacological properties. ET-1 is produced in endothelial cells and may be secreted in a similar way to some paracrine hormones. The pressor response of ET-1 is large...
journal_title:Journal of cardiovascular pharmacology
pub_type: 历史文章,杂志文章,评审
doi:10.1097/00005344-198900135-00002
更新日期:1989-01-01 00:00:00
abstract::Heart rate turbulence (HRT) denotes the baroreflex-mediated short-term oscillation of cardiac cycle lengths after spontaneous ventricular premature complexes. The physiological pattern of HRT consists of brief heart rate acceleration followed by more gradual heart rate deceleration before the heart rate returns to bas...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章,评审
doi:10.1097/FJC.0b013e3181d4c973
更新日期:2010-06-01 00:00:00
abstract::Dietary omega-3 polyunsaturated fatty acids (PUFAs) are readily incorporated into heart and skeletal muscle membranes where, in the heart, animal studies show they reduce O2 consumption. To test the hypothesis that omega-3 PUFAs alter O2 efficiency in humans, the effects of fish oil (FO) supplementation on O2 consumpt...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章,随机对照试验
doi:10.1097/FJC.0b013e3181911913
更新日期:2008-12-01 00:00:00
abstract::We studied the acute intravenous (i.v.) effects of the antiarrhythmic agents ibutilide, sematilide, lidocaine, and encainide in a canine Y-shaped right atrial incision model of atrial flutter. After baseline determination of atrial effective refractory period (AERP), sustained atrial flutter (AFL) was initiated by atr...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/00005344-199504000-00005
更新日期:1995-04-01 00:00:00
abstract::Stroke is a major clinical problem in hypertension. Cerebral hemorrhage has become considerably less frequent since treatment of hypertension has become more widely used. Antihypertensive treatment has also reduced the incidence of lacunar stroke, which is a result of hypertensive vascular disease of small arteries. C...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章,评审
doi:
更新日期:1990-01-01 00:00:00
abstract::Three-month-old spontaneously hypertensive rats were treated for 1, 2, or 3 months with daily intraperitoneal injections of naftidrofuryl (30 mg/kg). Systolic arterial pressure was measured. Tail arteries were removed and perfused at a constant flow rate of 2 ml/min. A concentration-response curve for serotonin was pr...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:
更新日期:1990-01-01 00:00:00
abstract::We studied the hemodynamic effects of four doses of milrinone, administered by intravenous (i.v.) infusion alone and after autonomic blockade with prazosin, propranolol, atropine, and clonidine. Plasma concentrations of milrinone (50-600 ng/ml) were similar to those used for the treatment of cardiac failure and were u...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/00005344-198705000-00002
更新日期:1987-05-01 00:00:00
abstract::We investigated the effects of the ATP-dependent K+ channel antagonist glyburide and the ATP-dependent K+ channel agonist pinacidil in a Langendorff-perfused rabbit isolated heart subjected to a period of global hypoxia. A class III antiarrhythmic drug, E-4031, also was studied in this model. These studies aimed to de...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/00005344-199302000-00001
更新日期:1993-02-01 00:00:00
abstract::Using cardiac microdialysis, we studied release of the adenine nucleotide breakdown products (ANBP) adenosine (ADS), inosine (INS), and hypoxanthine (HYP) into the interstitium of canine myocardium during 20- and 40-min occlusion of the anterior descending coronary artery and reperfusion. Dialysate ANBP concentrations...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/00005344-199212000-00017
更新日期:1992-12-01 00:00:00
abstract::We examined the involvement of the oxidative stress in high glucose-induced suppression of human aortic endothelial cell proliferation. Chronic glucose treatment for 72 h concentration-dependently (5.6-22.2 mol/l) inhibited human coronary endothelial cell proliferation. Temocaprilat, an angiotensin-converting enzyme i...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/00005344-200312001-00013
更新日期:2003-12-01 00:00:00
abstract::Recent in vitro experiments have shown that amrinone enhances the release of nitric oxide (NO) from the endothelium and induces NO mediated vasodilatation. This in vivo study examined whether amrinone causes vasodilatation mediated by endothelium-derived NO, and whether this effect is attenuated in patients with endot...
journal_title:Journal of cardiovascular pharmacology
pub_type: 临床试验,杂志文章
doi:10.1097/00005344-200008000-00008
更新日期:2000-08-01 00:00:00
abstract::The pharmacologic profile of SK-1080, a nonpeptide AT1-selective angiotensin-receptor antagonist, was investigated by receptor-binding studies, functional in vitro assays with rabbit and rat aorta, and in vivo experiments in pithed rats. SK-1080 inhibited the specific binding of [125I]-[Sar1, Ile8]-angiotensin II to h...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/00005344-199903000-00004
更新日期:1999-03-01 00:00:00
abstract::To evaluate the role of intracellular calcium and particularly Ca2+-uptake in the initiation of lymphocyte mitogenesis, the effect of mibefradil, which blocks both L- and T-type calcium channels with a more selective blockade of T-type channels, on the proliferation of human peripheral blood mononuclear cells (PBMCs) ...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/00005344-199904000-00012
更新日期:1999-04-01 00:00:00
abstract::Endothelin-1 (ET-1) stimulated cAMP formation in Chinese hamster ovary cells stably expressing human wild-type ET(A) (CHO/hET(A) cells) and inhibited the formation in cells expressing human wild-type ETB (CHO/hETB cells), suggesting a selective coupling of hET(A) and hETB with G alpha s and G alpha i, respectively. To...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:
更新日期:1995-01-01 00:00:00
abstract::Felodipine, a dihydropyridine calcium antagonist, was used to treat eight patients with severe uncontrolled hypertension: five had essential hypertension, two had renovascular disease, and one chronic pyelonephritis. Mean blood pressure (BP) was 221 +/- 14/120 +/- 4 mm Hg despite treatment with three or more antihyper...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/00005344-199015004-00032
更新日期:1990-01-01 00:00:00
abstract::The electromechanical effects of UK-68,798 (UK), a novel class III antiarrhythmic drug, were studied in guinea pig and rat papillary muscles (PMs) and atria in vitro using conventional microelectrode technique. UK (10(-8)-10(-6) M) prolonged the action potential duration (APD) by 21-58% and effective refractory period...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/00005344-199009000-00008
更新日期:1990-09-01 00:00:00
abstract::A hallmark of vascular disease is the inappropriate proliferative and synthetic behavior of smooth muscle cells. This phenotypically immature behavior arises as a consequence of the myocytes undergoing conversion from a contractile to proliferative/secretory cell type. The stimulus invoked for this dedifferentiative p...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章,评审
doi:
更新日期:1992-01-01 00:00:00
abstract::Endothelial cells and smooth muscle cells are the major cells that constitute blood vessels, and endothelial cells line the lumen of blood vessels. These 2 types of cells also play an integral role in the regional specialization of vascular structure. On the basis of these observations, we designed our study to invest...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/FJC.0b013e31803e8756
更新日期:2007-05-01 00:00:00
abstract::beta 2-Adrenoceptor function may be decreased in primary hypertension, resulting in increased peripheral resistance. To study the beta 2-adrenoceptor function, we used circulating mononuclear leukocytes (MNL) as a model system. Twenty untreated hypertensive subjects [(HT) 10 men and 10 women] and 20 age- and sex-match...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/00005344-199311000-00004
更新日期:1993-11-01 00:00:00
abstract::The aim of this study was to compare the hemodynamic effects of three nitric oxide (NO) donors [i.e., (+/-)-(E)-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (FK409), (+/-)-N-[(E)-4-ethyl-3-[(Z)-hydroxyimino]-6-methyl-5-nitro-3-he ptenyl]-3-pyridinecarboxamide (FR 146801) and isosorbide dinitrate (ISDN)] in rats. In...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章
doi:10.1097/00005344-199708000-00011
更新日期:1997-08-01 00:00:00
abstract::The oral anticoagulant edoxaban, a factor Xa inhibitor, will likely be coadministered with digoxin in some patients with atrial fibrillation. Both drugs are substrates for P-glycoprotein. The objective of this phase 1, parallel study was to assess the effects of coadministration of both drugs on their respective pharm...
journal_title:Journal of cardiovascular pharmacology
pub_type: 杂志文章,随机对照试验
doi:10.1097/FJC.0b013e31826265b6.
更新日期:2012-10-01 00:00:00
abstract::The efficacy and safety of carvedilol, a beta-blocker with vasodilatory properties, were compared with that of hydrochlorothiazide (HCTZ) both at a once-daily dose of 25-50 mg in a double-blind, randomized, parallel-group, multicenter study. Following a single-blind placebo phase of 3-6 weeks, 201 eligible patients (a...
journal_title:Journal of cardiovascular pharmacology
pub_type: 临床试验,杂志文章,多中心研究,随机对照试验
doi:
更新日期:1991-01-01 00:00:00