Eggs of oviparous amniotes can contain substantial quantities of several steroids at the time of oviposition. These maternally derived steroids appear to affect the phenotype of developing offspring, but not all steroid sensitive traits are affected by maternal steroids, and little is known about how these effects may arise. In ...

OBJECTIVES: Hypovolemia has occurs frequently in sepsis. Due to pathologically increased permeability of the capillaries, the fluid leaks to the interstitium. An adequate fluid therapy is the corner stone to achieve circulatory stabilization and sufficient tissue perfusion; on the other hand, according to the data from the literature a tissue ...

Intestinal barrier function in pigs after weaning is almost exclusively determined in terminal experiments with Ussing chambers. Alternatively, the recovery in urine of orally- administered lactulose can be used to assess intestinal permeability in living animals. This experiment was designed to study the barrier function of the small intestine of ...

An ethanolic extract of Antiaris toxicaria trunk bark showed potent in vitro cardiotonic effect on isolated guinea pig atria. Bioassay-guided fractionation of the extract led to identification of nine new cardiac glycosides (1-9, named antiarosides A-I), antiarotoxinin A (10), and 18 known compounds. Their structures were established using MS and ...

The cost of islet procurement from donor pigs is increased by the use of organs that produce low yields. We developed an assessment system using dithizone-stained pig pancreas biopsies to enable the preselection of donor organs. Pig pancreas biopsy slices were soaked in dithizone solution. The islets were evaluated before ...

OBJECTIVE: To differentiate between the effects of parasympathetic and sensorimotor stimulation of isolated mouse and guinea-pig bladders in vitro by measuring the pressure increases to electrical field stimulation (EFS) and then comparing the effects of botulinum neurotoxin A (BoNT-A) applied either to the lumen or to the external bathing medium. ...

Although metabolic response after partial hepatectomy has been well studied in animal models, there are few studies examining restoration of metabolic capacity after right hepatectomy in humans. The L-[1-(13)C]-phenylalanine breath test (PBT) is a simple non-invasive diagnostic tool which allows measurement of liver functional reserve. We investigated the PBT for ...

This thesis deals with the isolation and structural elucidation of bioactive naphthylisoquinoline alkaloids and related analogs. The mode of action of the antiplasmodial activity exhibited by the naphthylisoquinoline alkaloids was explored and compared to that of the antimalarial drug chloroquine. Furthermore, the phase 1 and 2 metabolism of dioncophyllines A ...

BACKGROUND: Porcine pancreas is a potential source of material for islet xenotransplantation. However, the difficulty in isolating islets, because of their fragility and the variability of isolation outcome in donor age and breed, represents a major obstacle to porcine islet xenotransplantation. In this study, we compared the islet isolation yield ...

Milled wood lignin (MWL), cellulolytic enzyme lignin (CEL), and enzymatic mild acidolysis lignin (EMAL) were isolated from different wood species and characterized by various techniques. The EMAL protocol offered gravimetric lignin yields 2-5 times greater than those of the corresponding MWL and CEL. The purities of the EMALs were 3.75-10.6% ...

Toxoplasma gondii infection is widely prevalent in humans in Brazil. Among the food animals, pigs are considered the most important meat source of T. gondii for infection in humans. In the present study, we report the first isolation of viable T. gondii from finishing pigs in Brazil. Antibodies to T. ...

The effects of the aqueous extract of the leaves of solenostemma argel were examined on the isolated rabbit aortic strip and guinea pig atria. The aqueous extract produced stimulatory effect on isolated rabbit aortic strip and this effect was not blocked by tolazoline. When added to isolated guinea pig atria ...

1. Doxorubicin (DOX), a standard chemotherapeutic anthracycline agent, causes a positive inotropic effect in guinea-pig isolated atria in a concentration-dependent manner with an ED(50) of 3.6 micromol/L. This increase in contractility is strictly related to the generation of reactive oxygen species (ROS) as a consequence of quinone metabolism. The ED(50) ...

A sting of the fish S. argus, a venomous edible spotted butterfish, produces tremendous local pain, severe swelling, rise of body temperature, throbbing sensation etc. To establish the pharmacological activities of S. argus sting extract, the present investigation, was carried out on experimental animals. The LD50 of extract was found ...

Among ten patients who contracted sporadic acute or fulminant hepatitis E between 2001 and 2002 in Hokkaido, Japan, nine (90 %) had a history of consuming grilled or undercooked pig liver 2-8 weeks before the disease onset. We tested packages of raw pig liver sold in grocery stores as food ...

Several hydroindenic derivatives (7a-methyl-2,3,5,6,7,7a-hexahydro-1H-indenes), bearing an amidinohydrazone at C-5 and different moieties at C-1, have been synthesized and evaluated for their inotropic and chronotropic effects on right- and left-guinea-pig-atria activity. Three of them showed the same profile as digoxin, although with lower potency. The effect on Na(+),K(+)-ATPase (NKA) was also ...

BACKGROUND: Although both positive chronotropic and inotropic effects of beta-adrenergic stimulation are thought to be mediated by cyclic adenosine 3'5'-monophosphate, phosphodiesterase III inhibitors such as amrinone and milrinone potentiate the positive inotropic effect of catecholamines with minimum influence on the heart rate in clinical setting. The aim of the current ...

A novel, potential antidepressant, E-6006 citrate (E-6039), dose-dependently reduced the vocalizations emitted by isolated guinea pig pups. The (+)-E-6006, but not the (-)-E-6006, enantiomer also reduced vocalizing. There were no reliable effects of E-6039 on locomotor activity, crouching, or other behavioral measures, but both E-6039 and the (+)-E-6006 enantiomer elevated ...

In myocardial preparations isolated from guinea pigs, 2-methyl-1, 4-naphthoquinone (menadione) causes an increase in contractility that is strictly related to the generation of reactive oxygen species (ROS) as a consequence of quinone metabolism. In heart, menadione undergoes one-electron reduction to semiquinone, a reaction mainly catalysed by mitochondrial NADH: ubiquinone oxidoreductase. ...

Acute effects of aflatoxins (AF), and in particular cardiac actions, have not been examined as much as chronic toxicity. Thus, in the present study we evaluated the effects of specific AF on isolated guinea pig atria. Isoprenaline (ISO, 4x10(-9)), AFB(1) (3x10(-6) and 6x10(-5) M) and AFG(1) (3x10(-6) and 6x10(-6) M) ...

While human islet allotransplantation is limited due to the shortage of donors, pig islet xenotransplantation appears to be a possible alternative. Enzymatic digestion is the method most commonly used for adult pig islet isolation, but since the description of the semiautomated isolation technique in the late 1980s, yields of pig ...

AIM: To investigate the effect of melittin (Mel) on isolated guinea pig atria. METHODS: The effect of Mel on the contraction and heart rate of isolated guinea pig atria at different concentrations was determined. RESULTS: Mel at a lower concentration (0.1-0.8 mumol.L-1) enhanced the contraction of left atria in a ...

In our previous experiments measuring acid secretion in the isolated mouse stomach we found higher EC50 values (agonist concentration, evoking half maximal effect) for histamine than in the experiments on the isolated guinea pig right atrium (contraction frequency). The difference could be due to nonequilibrium conditions in the isolated mouse ...

Isolated hepatocytes are a suitable system for the study of hepatic physiology and metabolism. They are also used for pharmacological and toxicological studies related to hepatic uptake, metabolism, excretion and toxicity of xenobiotics, as well as morphological and metabolic effects induced in the liver as a result of drug or ...

In papillary muscles, carbachol reduced the positive inotropic effects of isoprenaline (10 nmol/l). The negative inotropic effects of carbachol in isoprenaline-stimulated guinea pig papillary muscles were attenuated by additionally applied sodium fluoride (3 mmol/l). These effects of sodium fluoride were blocked by deferoxamine (200 micromol/l). In guinea pig left atria, ...

Guinea pig pups were injected subcutaneously with a corticotropin-releasing factor antagonist (CRF12-41) or saline vehicle and then placed into a novel cage for 30 or 60 min. Isolated 20- to 26-day-old pups vocalized more and exhibited more locomotor activity when given 15 to 150 micrograms of CRF12-41 than when given ...

1. Two new milrinone analogs, 3-acetyl-6-phenyl-2(1H)-pyridone (SF 348) and 3-acetyl-7-methyl-7,8-dihydro-2,5(1H, 6H) quinolinone (SF 349), increase the contractile activity of spontaneously beating and electrically driven atria isolated from reserpine-treated guinea-pigs. 2. Propranolol 0.1 microM drastically inhibits the contractile effect of SF 348, whereas that of SF 349 is unaffected. Preincubation of ...

The effects of ginsenoside Re on atria properties of guinea pigs were studied in vitro. Re decreased dose-dependently the contractile force and frequency of isolated guinea pig atria. The correlation of dose-effects of Re on autorhythmicity and contractility of atria was significant. 4.7 x 10(-8) M Re prolonged the effective ...

Neuropeptide Y exerts prejunctional effects on automaticity in cardiac pacemaker tissue and postjunctional effects on contractile activity of cardiomyocytes. It is uncertain whether neuropeptide Y has postjunctional effects on cardiac automaticity. This paper reports a study of the actions of exogenous neuropeptide Y (10(-10)-10(-6) M) on automaticity of isolated preparations ...

The purpose of the present study was to investigate the functional consequences of KATP modulation in the normal and the metabolically inhibited guinea-pig isolated diaphragm using the K+ channel openers cromakalim, pinacidil, RP49356 (N-methyl-2-(3-pyridil)-tetrahydrothiopyran-2-carbothiami de-1-oxide) and ZM260384 (2-(2,2-bis(difluoromethyl)-6-nitro-3,4-dihydro-2H-1,4-benzoxazine -4-yl)pyridine-N-oxide) and the K+ channel inhibitors glibenclamide, phentolamine and ciclazindol. All K+ ...

The action of hyperosmotic nutrient solutions on the depressive effects of carbofuran was studied on spontaneously contracting guinea pig atria. The force and frequency of contraction were recorded using an isotonic lever. Carbofuran 33.0 micrograms ml-1 produced a gradual depressive effect. The time for stabilization of the depressive effect was ...

Structures are proposed for the Inagami-Tamura endogenous digitalis-like factor (EDLF), and two possible candidates, (14 beta,15 beta,16 beta,17 alpha)- and (14 beta,15 alpha,16 alpha,17 alpha)-2,3,14,15,16,17-hexahydroxy-1,3,5(10)-estratrienes, were synthesized. Both compounds were potent in inducing a contractile response in isolated rat aorta and guinea pig left atrium.

1. Inotropic and chronotropic effects of beraprost sodium (beraprost), a chemically stable prostacyclin analogue, were examined in isolated myocardial preparations of guinea pigs. 2. In the left atria, 10(-9) - 10(-7) M beraprost had no significant effect on the contractile force, but 10(-6) and 10(-5) M produced a concentration-dependent positive ...

The recently synthesized benzofuranylethanolamines GE 68, GE 70, GE 76, RG 16 and RG 25, were studied in guinea-pig isolated papillary muscles and right atria. With regard to their inotropic, chronotropic and beta-adrenoceptor-blocking activity, these compounds were compared with the reference drug propafenone. GE 68, GE 70 and GE 76 ...

The metabolism of the organophosphonate herbicide glyphosate was investigated in 163 environmental bacterial strains, obtained by a variety of isolation strategies from sites with or without prior exposure to the compound. Isolates able to use glyphosate as sole phosphorus source were more common at a treated site, but much less ...

1. The local cardiac actions of substance P were examined in isolated perfused hearts and atria of the guinea-pig. 2. In both hearts and right atria, substance P caused negative inotropic and chronotropic effects. 3. Atropine (10(-6) M) or depletion of acetylcholine, by electrical stimulation and hemicholinium-3 perfusion, significantly attenuated ...

Effects of total Panax notoginseng saponins (PNS) and Panax notoginseng saponin monomers Rb1 and Rg1 (Rb1, Rg1) on total ATPase and Na(+)-K(+)-exchanging ATPase of guinea pig heart were studied. It was found that PNS inhibited the total myocardial ATPase, but had no significant effect on the myocardial Na(+)-K(+)-exchanging ATPase. The ...

The antagonist radioligand 1,3-[3H]dipropyl-8-cyclopentylxanthine ([3H]DPCPX) was used to characterize adenosine A1 receptors in membrane preparations from atrial and ventricular myocardium of rat, rabbit, guinea pig and pig. Kd values in crude membranes from guinea pig atria and ventricles (3.3 and 3.0 nM) were higher than those in the other species ...

The inotropic effects of isoprenaline, dobutamine and dopexamine were studied in human right atrial myocardium and in rat and guinea-pig left atria electrically stimulated at 1 Hz. To investigate the contribution of endogenously released catecholamines to the positive inotropic effects of beta-adrenoceptor agonists, experiments were performed both in the absence ...

Since guinea pig and rat atria have been used as models to study acute anthracycline-induced cardiotoxicity, experiments were carried out in these preparations to evaluate possible acute cardiac effects mediated by mitoxantrone (MTX). After a latency period of approximately 90 min, MTX (10(-5)-10(-4) M) promoted a concentration-related and time-dependent decrease ...

The present study describes an in vitro method to characterize inotropic and vascular effects of compounds on isolated human cardiovascular tissues. In vitro, the positive inotropic effect in electrically driven left ventricular papillary muscle strips of nonfailing and failing human myocardium was studied and compared to experiments performed in muscle ...

In guinea pig and rat cardiac tissue, redox cycling benzoquinones (2,5-dimethyl-p-benzoquinone and duroquinone) and naphthoquinones (menadione and 2,3-dimethoxy-1,4-naphthoquinone) generated superoxide anion (O2-.) both through one- and two-electron reductions, the generation being significantly greater in guinea pig than in rat tissue. In electrically driven left atria isolated from guinea pig and ...

The beta-adrenoceptor blocking effects of the bopindolol (Wandonorm, CAS 62658-63-3) metabolites 18-502 (indole-2,4- methylaminopropoxy(N-tert.butyl)-tartrate) and 20-785 (indole-2,4-carboxyaminopropoxy(N-tert.butyl] were studied in electrically stimulated guinea-pig left atria and in spontaneously beating guinea-pig atria in vitro. Both compounds shifted the concentration-response curve of isoprenaline to the right, but did not reduce the maximum ...

A series of fluorenyl analogues of verapamil were synthesized and their cardiovascular properties on guinea pig isolated atria and isolated perfused heart evaluated. The compounds were also tested for their calcium antagonistic activity on guinea pig aorta. They were found to be poor calcium antagonists, but showed negative inotropic and ...

The in vitro chronotropic and inotropic effects of norepinephrine and acetylcholine in isolated right and left guinea pig atria were examined in the absence and presence of halothane, isoflurane, and enflurane (0.6 and 1.2 MAC). All three anesthetics elicited dose-dependent reductions in contractile force and spontaneous pacemaker activity. The maximal ...

Dopaminergic agonist apomorphine (Apo, 1-100 mumol.L-1) had a concentration-dependent positive inotropic effect on guinea pig left atria. This effect was not changed obviously when the influences of sympathetic and parasympathetic nerves were eliminated by reserpine and atropine, respectively. Apo had little inotropic action on guinea pig papillary muscles. The time ...

Ketamine is a cardiovascular stimulant through its sympathomimetic effects; however, its direct inotropic effect has been reported as positive in rat and negative in rabbit ventricular myocardium. This study reexamines the effect of ketamine on the contractile properties of mammalian ventricular myocardium. In isolated, electrically stimulated ferret right ventricular papillary ...

Supersensitivity was induced by injection of guinea pigs with reserpine, 0.1 mg/kg/day for 7 days. This treatment induced chronotropic supersensitivity of isolated right atria to isoproterenol but not to forskolin. The pretreatment induced supersensitivity to the cyclic AMP-generating effects of isoproterenol or forskolin in left, but not right, atria. These ...

Recently several non catecholamine, non glycoside cardiotonic drugs have been described. New compounds include amrinone, sulmazole, milrinone and pimobendan. In an attempt to alleviate anthracycline toxicity, we have previously reported that these compounds reduced the negative inotropic effect of adriamycin, 4-epiadriamycin and esorubicin in isolated guinea pig atria. The present ...

A series of 2-substituted 1H-imidazo[4,5-b]pyridines and the isomeric 1H-imidazo[4,5-c]pyridine derivatives has been prepared and evaluated as inotropic agents. The 1H-imidazo-[4,5-b] derivatives were found to be consistently more potent than their isomers in the [4,5-c] series in isolated guinea pig papillary muscle preparations. Structure-activity relationships and the species-dependence of inotropic potencies ...