Pharmacological activity of the essential oil of Satureja viminea (Lamiaceae)

The aqueous extract and the essential oil of Satureja viminea (Lamiaceae) were tested. General physiologic effects were assessed through the Hippocratic screening test. Non fasted female Sprague Dawley rats were utilized and 250, 500, 750 and 1000 mg/kg doses were used. Two animals were used for each dosage level and for the vehicle alone. Exploratory behavior and curiosity were measured using a hole board apparatus and placing non-trained mice on the board and recording the number of holes explored in a 5 minute period. The Boissier chimney test was used to evaluate motor coordination. Muscle strength was assessed through a grasping test where mice were hung by their fore-limbs 40 cm above the base on a horizontal metal stainless bar. In all these tests, 3 groups of 6 albino mice, were treated with 1000 mg/kg of each the essential oil of S. viminea, the vehicle and diazepan (1 mg/kg) as a positive control. Analgesic activity was explored in Sprague-Dawley rats. The tail flick method described by D'Amour and Smith (1941) modified by CYTED was implemented on three groups (6 rats each) of animals treated with, each the essential oil of S. viminea (1000 mg/kg), the vehicle and indomethacine. The test was carried out just before and 30, 60 and 120 min after oral treatment. Peristaltic activity was measured in albino mice, three groups of 6 animals each, treated orally with each the essential oil of S. viminea (1000 mg/kg), the aqueous extract (1000 mg/kg), and the vehicle. The marker used was activated carbon. Animals were sacrificed 30 min after the marker was given and the percent of total small intestine traversed by it was calculated. Also a lethal dose 50 (LD 50) was determined with the Spearman-Karber method. A dose-related spontaneous motor activity reduction was observed. Exploratory behavior and curiosity were diminished. The grasping strength of mice was reduced. A very clear and significant analgesic effect was observed with the oral administration of the essential oil of S. viminea (1000 mg/kg). This effect is compared to that of indomethacine. Intestinal transit and gastric emptying were inhibited by the essential oil. The LD50 of the essential oil of S. viminea is 556.8 mg/kg.

Pharmacological activity of the essential oil of Satureja viminea (Lamiaceae).

The aqueous extract and the essential oil of Satureja viminea (Lamiaceae) were tested. General physiologic effects were assessed through the Hippocratic screening test. Non fasted female Sprague Dawley rats were utilized and 250, 500, 750 and 1000 mg/kg doses were used. Two animals were used for each dosage level and for the vehicle alone. Exploratory behavior and curiosity were measured using a hole board apparatus and placing non-trained mice on the board and recording the number of holes explored in a 5 minute period. The Boissier chimney test was used to evaluate motor coordination. Muscle strength was assessed through a grasping test where mice were hung by their fore-limbs 40 cm above the base on a horizontal metal stainless bar. In all these tests, 3 groups of 6 albino mice, were treated with 1000 mg/kg of each the essential oil of S. viminea, the vehicle and diazepan (1 mg/kg) as a positive control. Analgesic activity was explored in Sprague-Dawley rats. The tail flick method described by D'Amour and Smith (1941) modified by CYTED was implemented on three groups (6 rats each) of animals treated with, each the essential oil of S. viminea (1000 mg/kg), the vehicle and indomethacine. The test was carried out just before and 30, 60 and 120 min after oral treatment. Peristaltic activity was measured in albino mice, three groups of 6 animals each, treated orally with each the essential oil of S. viminea (1000 mg/kg), the aqueous extract (1000 mg/kg), and the vehicle. The marker used was activated carbon. Animals were sacrificed 30 min after the marker was given and the percent of total small intestine traversed by it was calculated. Also a lethal dose 50 (LD 50) was determined with the Spearman-Karber method. A dose-related spontaneous motor activity reduction was observed. Exploratory behavior and curiosity were diminished. The grasping strength of mice was reduced. A very clear and significant analgesic effect was observed with the oral administration of the essential oil of S. viminea (1000 mg/kg). This effect is compared to that of indomethacine. Intestinal transit and gastric emptying were inhibited by the essential oil. The LD50 of the essential oil of S. viminea is 556.8 mg/kg.

Consumo de micronutrientes con función antioxidante en estudiantes de la Universidad de Costa Rica, con edades comprendidas ente los 17 y 19 años / Consumption of micronutrients with antioxidants functions in students of the Universidad de Costa Rica, with ages between the 17 and 19 years

Objetivos: Determinar el consumo de alimentos fuentes de micronutrientes con función antioxidante en individuos de 17 a 19 años. Sitio de realización: Faculatad de Medicina, Universidad de Costa Rica. Materiales y Métodos: La muestra estuvo constituida por 150 estudiantes universitarios de 17 a 19 años de edad,seleccionados al azar, a los cuales se les evaluó la ingesta de micronutrientes con función antioxidante, utilizando el método denominado dieta usual, y se estimaron las cantidades consumidas mediante el catálogo de fotografías de porciones comúnmente utilizadas en Costa Rica. Para procesar la información se utilizó el programa Nutrionist IV. Resultados: Al menos el 75 por ciento de los sujetos de la muestra cubren las recomendaciones establecidas para vitamina E, vitamina C, selenio, cobre, cinc y manganeso. Unicamente el 25 por ciento de la muestra cubre las recomendaciones para beta carotenos. Conclusión: Los resultados de esta investigación revelan un adecuado consumo de casi la totalidad de los micronutrientes con función antioxidante, ya que para la mayoría de las vitaminas y minerales analizados sobrepasa el 100 por ciento de la cantidad recomendada para este grupo de edad. Sin embargo, este no es el caso para el consumo de beta carotenos, los cuales presetan un déficit importante en los porcentajes de adecuación. Se recomienda por lo tanto, la creación de programas de educación e intervención nutricional dirigidos a estudiantes universitarios, para fortalecer los hábitos alimentarios que están permitiendo que actualmente el consumo de micronutrientes con función antioxidante sea el adecuado y promover además el consumo de aquellos alimentos fuentes de beta carotenos, principalmnte vegetales verdes y amarillos que se encuentran deficientes en la dieta de esta población. Palabras claves: nutrición, adolescentes, antioxidantes, micronutrientes, beta carotenos.

Hypotensive action of an aqueous extract of Pimenta dioica (Myrtaceae) in rats

The intra-venous (i.v.) hypotensive action of the final aqueous fraction of Pimenta dioica was studied in Spontaneously Hypertensive Rats (SHR). The rats were anaesthetized (sodium pentobarbital 50 mg/kg), the trachea, right carotid artery and jugular vein were cannuated for adequate ventilation, direct blood pressure measurement and intra-venous administration of extract, solutions and drugs. The arterial line was connected to a pressure transducer (Viggo-Spectramed model P23 XL) and a polygraph (Grass model 7H) and monitored continuously during the firts five minutes after plan extract administration and then at 5 and 15 minute intervals for one hour. Responses were taken as the maximum pressure changes observed during this period. Increasing doses of the final aqueous fraction were given i.v. to groups of six SHR each. It produced a dose dependent decrease in blood pressure and the ED50 was 45 mg/kg. To discard that the hypotensive effect of the extracts was due to its ionic composition, a solution containing KCl, NaCl, CaCl2 adn MgCl2 equivalent to hte ion contents present in a dose of 50mg/kg of total asqueous extract was injected to Sprague-Dawley rats (SDN) using the same method as described above. It did not produce singificant changes in blood pressure. Pharmacological antagonistic studies were done injection either autonomic ganglion,alfa adrenoceptor,beta adrenoceptor and cholinergic receptor blockers prior to extract administration in SHR rats. Atropine, propranolol and phentolamine did no affect the hypotensive effect to the final aqueous fraction. With hexamethonium (autonomic ganglion blocker) the hypotensive response was diminished in a significant way (p<0.05). The hypotensive action of the final aqueous extract was not mediated through cholinergic, alfa o beta adrenergic receptors. The extract may posses vasorelaxing activity which could no be eviden after autonomic ganglion blockade due to extreme vasodilation present prior to extract administration. Future studies should address the question of a possible direct vasodilating effect of the extracts. Key words: Pimenta dioica, traditional medicine, herbal medicine, antihypertensive effect, arterial hypertension

Mecanismo de la respuesta celular a las señales extracelulares mediada por canales iónicos y receptores intracelulares / Mechanism of the cellular response a the median extracellular signals for ionic channel and intracellular receptors

En este artículo, se revisa el mecanismo de respuesta celular para mensajeros que actúan por medio de receptores de membrana con canal iónico incorporado o de receptores intracelulares, también conocidos como esteroides. Los principales ligandos para los receptores con canal iónico son neurotransmisores que al cambiar la conductancia de la membrana celular a iones como el sodio, potasio, calcio y cloruro modifican la excitabilidad de las células blanco. Los receptores esteroides se localizan intracelularmente, en el citosol o en el núcleo. Las hormonas que actúan a través de este tipo de receptor después de penetrar la membrana celular forman un complejo con el receptor que regula la transcripción genética.