Evaluation of the acute toxicity, analgesic and CNS activities of different species ofTeucrium genus

Methanol and dichloromethanol extracts of the leaves and stems of four Teucrium species (T. cartaginenses, T. flavum, T. pumillum and T. buxifolium) have been tested for their toxicity, analgesic and central depressor effects. The intraperitoneal administration of the different extracts showed a CNS depressant activity in mice, but they lacked anticonvulsive effects. When tested for analgesic activity none of the extracts increased the threshold of pain thermal stimulus. However, the methanol and dichloromethanol extracts of T. cartaginenses and T. buxifolium species showed a significant analgesic effect in models of pain induced by chemical or mechanical stimulation.

Effects on Arterial Blood Pressure of Methanol and Dichloromethanol Extracts fromJuniperus oxycedrus L.

The present study analysed the effect of the methanol and dichloromethanol extracts from Juniperus oxycedrus on arterial blood pressure in anaesthetized rats. The arterial blood pressure of normotensive rats was significantly reduced by the i.v. administration of both extracts. The hypotensive effect of these extracts was independent of the adrenergic system. These results may explain the vasorelaxing actions observed in other Juniperus species.

Antiinflammatory activity and effects on isolated smooth muscle of extracts from differentTeucrium species

The present study analyses the antiinflammatory effects and the action on in vitro motility of methanol and dichloromethanol extracts and stems of four Teucrium species (T. flavum, T. cartaginenses, T. buxifolium and T. pumillum). The antiinflammatory activity was tested in the carrageenan-induced paw oedema in rats. T. flavum methanol (200 mg/kg, i.p.) and dichloromethanol (138 mg/kg, i.p.) extracts showed a significant anti-inflammatory effect through the 24 h experimental period and reduced the Emax induced by histamine and serotonin in vitro on guinea-pig ileum and rat uterus respectively. These extracts did not modify the contractile effects induced by acetylcholine on rat duodenum and…

Low endotoxemia prevents the reduction of gastric blood flow induced by NSAIDs: role of nitric oxide

1 The role of nitric oxide (NO) in the effects of low endotoxemia on gastric damage and blood flow has been evaluated in indomethacin-treated rats. 2 Pretreatment (-1 h) with endotoxin (40 micro g kg(-1)) reduced gastric damage induced by indomethacin (20 mg kg(-1)) in conscious rats. 3 Endotoxin prevented the reduction in gastric blood flow (laser Doppler flowmetry) induced by indomethacin in pentobarbital-anaesthetised rats. 4 Pretreatment with an NO-synthase (NOS) inhibitor (L-NAME, 1 mg kg(-1)) reversed the protective effect of endotoxin on gastric blood perfusion. 5 Endotoxin did not modify the expression of mRNA for endothelial NOS or inducible NOS in the gastric corpus when evaluated…

Pharmacological evaluation of the dichloromethanol extract fromInula crithmoides L.

The pharmacological effect of the dichloromethanol extract of Inula crithmoides L. was analysed in in vitro and in vivo models. The extract dose-dependently decreased arterial blood pressure and furthermore it showed low acute toxicity, CNS depressor activity and analgesic and antiinflammatory effects. Preincubation of the guinea-pig ileum and rat duodenum (100 μg/mL) produced a significant reduction in the contractile effects of histamine and acetylcholine and a concentration-related inhibition of the effects of serotonin. Following further fractionation the methylene chloride/acetone (50/50) fraction caused a significant decrease in motor activity and significantly reduced the threshold o…

The analgesic-antiinflammatory extract fromAraujia sericifera lacks ulcerogenic activity on stress-gastric damage model

The present study evaluates the ulcerogenic activity of the hexane extract from dry fruits of Araujia sericifera in an experimental model of cold-restraint stress. Treatment of rats with 200 mg/kg (i.p.) of hexane extract did not affect the gastric lesions induced by cold-restraint stress. However, it was confirmed that a dose of 300 mg/kg (i.p.) of acetylsalicylic acid (ASA) which induced a similar analgesic-antiinflammatory effect, increased significantly the level of gastric damage. Thus, the hexane extract from the fruits of A. sericifera seems to possess analgesic-antiinflammatory properties which are not linked to gastrolesive effects.

Effects on Arterial Blood Pressure of the Methanol and Dichloromethanol Extracts from Schinus molle L. in Rats

The effects on arterial blood pressure of the methanol and dichloromethanol extracts from Schinus molle L. were analysed in urethane anaesthetized rats. In normotensive rats, the mean arterial blood pressure was significantly reduced by the i.v. administration of both extracts. The dichloromethanol extract inhibited the effects of noradrenaline on arterial blood pressure in the anaesthetized rat and it reduced the maximal contractile effect (Emax) induced by noradrenaline on rat vas deferens in the organ bath. However, the methanol extract did not modify the effects of noradrenaline in the evaluated tests.

Analgesic Activity and Effects on Isolated Smooth Muscle of Different Fractions of Hexane Extract fromAraujia sericifera Brot

The present study analyses the analgesic activity and action on in vitro motility of methanol soluble and methanol insoluble fractions obtained from the hexane extract of fruits from Araujia sericifera. The methanol fraction did not show any pharmacological activity on the different tests evaluated. However, the insoluble methanol fraction exhibited an interesting analgesic effect in models of chemical and thermal stimulus and it reduced the E max induced by histamine in vitro on guinea-pig ileum. This extract lacked any central depressor activity since it did not modify the number of mouse movements in the activity cage.

A pharmacological study ofAraujia sericifera B. extracts in rodents

The present study analyses the pharmacological activity in in vitro and in vivo models of different extracts obtained from Araujia sericifera. The hexane extract of fruits lacked toxicity, but exhibited an analgesic effect in models of chemical and thermal stimulation. Such an extract was the only one which exhibited antiinflammatory actions. The intrinsic effect on arterial blood pressure was biphasic: at low doses it significantly increased blood pressure, whereas at high doses it exerted the opposite effect. On isolated organs it produced a marked decrease in the maximum effect of histamine and acetylcholine. The dichloromethanol extract of fruits decreased arterial pressure and the maxi…

Cardiovascular effects of the methanol and dichloromethanol extracts fromTeucrium flavum L.

The effects on arterial blood pressure and heart rate of the methanol and dichloromethanol extracts from Teucrium flavumL. were analysed in urethane anaesthetized rats. Mean arterial blood pressure was significantly reduced by the i.v. administration of both extracts to normotensive rats. The methanol extract also induced a decrease in the heart rate, while the dichloromethanol extract lacked any effect on this parameter. © 1998 John Wiley & Sons, Ltd.

Evaluation of the analgesic and CNS actions of different fractions from the methanol extract ofTeucrium flavum L.

Different fractions (F.1, F-3, F-5, F-6, F-7, F-8) of the methanol extract from Teucrium flavum L. have been tested for their central nervous system and analgesic activities at a dose of 200 mg/kg. Fractions F-1, F-3 and F-7 showed CNS depressant activity, while fractions F-5, F-6 and F-8 had a slight CNS stimulant action. Fractions F-5, F-6, F-7 and F-8 were responsible for the analgesic activity of the extract.

Evaluation of the analgesic action of different fractions from the methanol extract of Teucrium buxifolium L

Different fractions (F-2, F-3, F-5) of the methanol extract from Teucrium buxifolium L. have been tested for their analgesic activity in mice. All of them exhibited peripheral analgesic activity except F-3, Fraction F-5 had the strongest effect and was subjected to a second re-extraction. The subfractions obtained (F-5/3 and F-5/8) exhibited a similar activity to that observed with the whole fraction. (C) 1998 John Wiley & Sons, Ltd.

Cardiovascular effects of the methanol and dichloromethanol extracts fromTeucrium cartaginenses L.

Methanol and dichloromethanol extracts of the leaves and stems of Teucrium cartaginensesL. have been tested for their effects on resting arterial blood pressure, heart rate and noradrenaline induced hypertension. Both extracts administered i.v. to urethane anaesthetized normotensive rats reduced mean arterial blood pressure and heart valve, while only the dichloromethanol extract prevented noradrenaline induced hypertension. © 1998 John Wiley & Sons, Ltd.

INTERACTION BETWEEN NORADRENALINE AND DOPAMINE IN THE ISOLATED GUINEA-PIGATRIA

Mechanisms of gastroprotection by transdermal nitroglycerin in the rat

Nitric oxide (NO) donors prevent experimentally-induced gastric mucosal damage, but their clinical utility is limited by short duration of action or unsuitability of the pharmaceutical form employed. This study analyses the gastroprotection elicited by a clinically used mode of continuous administration of an NO donor, namely the nitroglycerin patch. Application to rats of a transdermal patch that releases doses of nitroglycerin comparable to those used in man (40, 80, 160 and 400 ng min(-1) rat(-1)) reduced gastric damage induced by indomethacin (25 mg kg(-1), p.o. or s.c.). The nitroglycerin patch (160 ng min(-1) rat(-1)) also diminished damage by oral administration (1 ml) of acidified b…

Cardiovascular effects of the methanol and dichloromethanol extracts fromMentha suaveolensEhrh.

Methanol and dichloromethanol extracts of the leaves and stems of Mentha suaveolens Ehrh. have been tested for their effects on resting arterial blood pressure, heart rate and noradrenaline induced hypertension. Both extracts administered by i.v. bolus to urethane anaesthetized normotensive rats reduced the mean arterial blood pressure and heart rate, while only the dichloromethanol extract prevented the noradrenaline induced hypertension.

Pharmacological properties of the methanol extract from Mentha suaveolens Ehrh.

The present study analyses the pharmacological activity in in vivo and in vitro models of the methanol extract obtained from the leaves and steams of Menta suaveolens Ehrh. This extract lacked toxicity, but exhibited a central nervous system depressant action; an analgesic effect in models of chemical and mechanical stimulation suggesting the induction of a peripheral analgesic response. The extract also exhibited an antiinflammatory action inhibiting the rat paw oedema induced by carrageenin. Moreover, the in vitro studies showed a significant diminution in the contractile effects induced by histamine, serotonin and acetylcholine.

Effects on arterial blood pressure of the methanol extracts from differentTeucriumspecies

Methanol extracts of the leaves and stems of two Teucrium species (T. pumillum L. and T. buxifolium L.) have been tested for their effects on resting arterial blood pressure. Both T. pumillum L. and T. buxifolium L. extracts reduced mean arterial blood pressure in a dose dependent manner when administered i.v. to urethane anaesthetized normotensive rats. © 1997 John Wiley & Sons, Ltd.

Angiotensin II is involved in nitric oxide synthase and cyclo-oxygenase inhibition-induced leukocyte-endothelialcell interactionsin vivo

Chronic inhibition of nitric oxide synthase (NOS) provokes a hypertensive state which has been shown to be angiotensin II (Ang-II) dependent. In addition to raising blood pressure, NOS inhibition also causes leukocyte adhesion. The present study was designed to define the role of Ang-II in hypertension and in the leukocyte-endothelial cell interactions induced by acute NOS or cyclo-oxygenase (COX) inhibition using intravital microscopy within the rat mesenteric microcirculation. While pretreatment with an Ang-II AT1 receptor antagonist (losartan) reversed the prompt increase in mean arterial blood pressure (MABP) caused by indomethacin, it had no effect on the increase evoked by systemic L-…

Pharmacological Screening of DifferentJuniperus oxycedrusL. Extracts

Methanol and dichloromethanol extracts of leaves and stems of Juniperus oxycedrus have been tested for their toxicity, analgesic, antiinflammatory and central effects. Both extracts showed low acute toxicity and decreased spontaneous motility. The methanol extract exhibited an analgesic effect in models of chemical, mechanical and thermal stimulation whereas dichloromethanol extract showed only a significant effect in models of pain induced by chemical stimulation. Both extracts showed a significant antiinflammatory activity and inhibition of the rat paw oedema induced by carrageenin.

In vitro pharmacological evaluation of the dichloromethanol extract fromSchinus molle l.

The pharmacological activity of the dichloromethanol extract of Schinus molle L. (SM-DCM) was analysed in in vitro models. Preincubation of the isolated guinea-pig ileum or rat uterus preparations with the extract (100 μg/mL) abolished the contractile effects of histamine and serotonin respectively. At the same dose, the extract partially reduced the contractile effects of acetylcholine on the isolated rat duodenum. A 10 μg/mL dose showed an inhibitory effect on histamine and serotonin, but not on acetylcholine-induced contractions (NS). No significant effect was found with a 1 μg/mL dose. © 1998 John Wiley & Sons, Ltd.

Pharmacological screening of the methanol and dichloromethanol extracts ofGenista patens

The pharmacological effects of the dichloromethanol and methanol extracts obtained from leaves and stems of Genista patens DC were analysed in in vitro and in vivo models. Both extracts showed low acute toxicity (LD 50 >3 g/kg), CNS depressor and antiinflammatory activity, and similar analgesic effect in models of chemical and thermal stimulation. Furthermore, the dichloromethanol extract (1-20 mg/kg) induced a pronounced dose-dependent decrease on blood pressure. On isolated organs, the dichloromethanol extract (1, 10, 100 μg/mL) shifted the concentration-effect curve to the right for ACh and reduced the E max induced by histamine without modifying responses induced by noradrenaline and se…

In vitro studies of methanol and dichloromethanol extracts ofJuniperus oxycedrus L.

The present study evaluated the effect of methanol and dichloromethanol extracts obtained from the leaves and stems of Juniperus oxycedrus against neurotransmitter-induced contraction in different isolated tissues of rats and guinea-pigs. Diverse concentrations of these extracts inhibit the concentration curve response to histamine, serotonin and acetylcholine. These results contribute to explaining the use of this plant in folk medicine. © 1997 John Wiley & Sons, Ltd.

Analgesic and central depressor effects of the dichloromethanol extract fromSchinus molle L.

The analgesic and central depressor effects of the dichloromethanol extract of Schinus molle L. were analysed in in vivo models. This extract showed low acute toxicity, CNS depressor activity and analgesic effect. Following further fractionation, the hexane/dichloromethane (75/25) fraction showed the most interesting results. Thus, this fraction caused a total inhibition of motor activity and significantly reduced the threshold of pain to chemical stimulus. © 1997 John Wiley & Sons, Ltd.

Globularia alypumL. extracts reduced histamine and serotonin contractionin vitro

The present study analyses in in vitro models the pharmacological activity of methanol and dichloromethane extracts (1, 10 and 100 microg/mL) obtained from the leaves and stems of Globularia alypum L. Preincubation of the guinea-pig ileum and rat uterus with both extracts produced a dose dependent abolition of the contractile effects of histamine and serotonin, respectively. At the same doses, neither methanol nor dichloromethane extract reduced the contractile effects of acetylcholine on rat duodenum or noradrenaline on rat vas deferens.