Influencia adrenérgica y colinérgica sobre la producción de especies reactivas de oxígeno en neutrófilos humanos* / Adrenergic and cholinergic influence on the production of reactive oxygen species in human neutrophils*

RESUMEN Objetivos. Determinar y comparar el efecto de fármacos agonistas adrenérgicos y colinérgicos sobre la producción de especies reactivas de oxígeno (ROS) en neutrófilos de individuos sanos. Materiales y métodos. Se tomaron muestras de sangre total de cinco participantes para purificar los neutrófilos mediante el método de gelatina. Se midió la producción de ROS por quimioluminiscencia (QLM) usando un contador de centelleo y forbol-12-miristato-13-acetato (PMA) como estímulo. También se realizaron pruebas sin PMA para medir la producción espontánea. Posteriormente, con el mismo método se midió la formación de ROS en presencia de nicotina (agonista colinérgico), salbutamol y clonidina (agonistas adrenérgicos), cada uno en concentraciones de 10-2 M, 10-3 M, 10-4 M y 10-5 M. Se calculó el área integrada bajo las curvas de QLM y se halló el porcentaje de inhibición o de estimulación según sea el caso. Se comparó el efecto provocado por las drogas con sus controles correspondientes y se realizó el análisis estadístico. Resultados. Se obtuvo una disminución de la producción de ROS como efecto de las sustancias estudiadas con una diferencia significativa entre los controles y el efecto producido a 10-2 M, 10-3 M y 10-4 M. Este efecto aumentó de intensidad conforme la concentración de las drogas se incrementó. Los mayores porcentajes de inhibición se mostraron a 10-2 M y 10-3 M. Salbutamol presentó los máximos valores con todas las concentraciones con diferencia significativa entre su inhibición y la generada por las demás drogas. Conclusiones. Los estímulos adrenérgico y colinérgico tienen un efecto inhibitorio de la producción de ROS en neutrófilos de individuos sanos.

ABSTRACT Objectives. To determine and compare the effect of adrenergic and cholinergic agonist drugs on the production of reactive oxygen species (ROS) in neutrophils of healthy individuals. Materials and Methods. Whole blood samples were taken from five participants to purify neutrophils using the gelatin method. The production of chemiluminescent (QLM) ROS was measured using a scintillation counter and phorbol-12-myristat-13-acetate (PMA) as a stimulus. Non-PLA tests were also conducted to measure spontaneous production. Subsequently, with the same method, ROS formation was measured in the presence of nicotine (cholinergic agonist), salbutamol, and clonidine (adrenergic agonists), each in concentrations of 10-2 M, 10-3 M, 10-4 M, and 10-5 M. The area integrated under the QLM curves was calculated and the percentage of inhibition or stimulation was found as the case may be. The effect of the drugs was compared with their corresponding controls and statistical analysis was carried out. Results. A decrease in the production of ROS was obtained as an effect of the substances studied with a significant difference between the controls and the effect produced at 10-2 M, 10-3 M, and 10-4 M . This effect increased in intensity as drug concentration increased. The highest percentages of inhibition were shown at 10-2 M and 10-3 M. Salbutamol presented the maximum values with all the concentrations with a significant difference between its inhibition and that generated by the other drugs. Conclusions. Adrenergic and cholinergic stimuli have an inhibitory effect on the production of ROS in neutrophils of healthy individuals.

Effects of experimental amitraz intoxication in cats

This work studied the effects of experimental amitraz intoxication in cats. Sixteen cats were randomly divided equally into two groups: amitraz group - animals received 1.5 percent amitraz at 1mg/kg IV; and the control group - animals without amitraz. Physiological parameters from blood, cardiorespiratory system, and sedation indicators were quantified over time up to 360 minutes. Blood profile, urea, creatinine, alananine aminotransferase and aspartate aminotransferase were not affected by amitraz. Sedation, loss of reflexes, hypothermia, bradycardia, bradyarrhythmia, hypotension, bradypnea, mydriasis, besides transitory hyperglycemia, hypoinsulinemia and decrease of cortisol levels were observed in cats experimentally exposed to amitraz. The alpha2-adrenergic effects induced by amitraz intoxication in cats are very similar to the same effects reported in others species, contributing with more information about this type of intoxication to veterinary toxicology

Este trabalho estudou os efeitos da intoxicação experimental por amitraz em 16 gatos, distribuídos, aleatoriamente, em dois grupos: grupo amitraz - animais receberam amitraz a 1,5 por cento na dose de 1,0 mg/kg IV; e grupo controle - animais sem amitraz. Parâmetros fisiológicos sangüíneos, do sistema cardiorespiratório e de sedação foram aferidos até 360min. Perfil sangüíneo, uréia, creatinina, alanina aminotransferase e aspartato aminotransferase não foram afetados pelo amitraz. Sedação, perda de reflexos, hipotermia, bradicardia, bradiarritmias, hipotensão, bradipnéia, midríase, além de transitória hiperglicemia, hipoinsulinemia e diminuição dos níveis de cortisol, foram observados nos gatos experimentalmente expostos ao amitraz. Os efeitos alfa 2-adrenérgicos induzidos pela intoxicação por amitraz em gatos são muito similares aos mesmos efeitos relatados em outras espécies, contribuindo com mais informações dessa intoxicação para a toxicologia veterinária

Comparison of the effect of sympathetic agonist and antagonist on rabbits perfused heart: a study on simple and succussed dilutions

The pharmacological effect of Adrenaline and Atenolol dilutions / succussion is still unexplainable for their reverse effect on tissues. This effect of potentization is observed in the recent study with differences in the effect of simple and succussed dilutions on heart rate. For this purpose, both simple and succussed dilutions of Adrenaline and Atenolol were prepared serially, ranging from 10 [-3] to 10 [-36] for testing on the isolated perfused Rabbit's heart. Langendorff heart assembly was used to perfuse the heart and its activity was recorded on Oscillograph through isotonic transducer. The significant difference between the effects of simple and succussed dilutions of Adrenaline at 10 [-3] and 10 [-4] and for Atenolol 10 [-5], 10 [-11], 10 [-27], 10 [-30], 10 [-33] and 10 [-36] was observed on heart rate respectively. This study confirms that there are differences in the effects of simple and succussed dilutions. While potentization or reverse effect observed than normal has been found in-consistently throughout the range of dilutions used. Thus in-consistency expresses the instability of change in parent drug molecule on succussion

Selective destruction of nigrostriatal dopaminergic neurons does not alter [3H]-ryanodine binding in rat striatum

Dopamine nigrostriatal neurons are important for motor control and may contain a particularly dense population of ryanodine receptors involved in the control of dopamine release. To test this hypothesis, we used a classical model of unilateral selective lesion of these neurons in rats based on 6-hydroxydopamine (6-OHDA) injection into the substantia nigra. Binding of [3H]-GBR 12935, used as a presynaptic marker since it labels specifically the dopamine uptake complex, was dramatically decreased by 83-100 percent in striatum homogenates after 6-OHDA lesion. On the contrary, no reduction of [3H]-ryanodine binding was observed. The present data indicate that [3H]-ryanodine binding sites present in rat striatum are not preferentially localized in dopaminergic terminals

Angiotensin induced changes in blood glucose level.

Angiotensin given by intravenous route in rabbits caused a marked rise in blood glucose within 45 min. Guanethidine, bretylium, alpha methyl DOPA, adrenalectomy and reserpinization significantly influenced the changes in blood glucose induced by angiotensin II. It is suggested that the rise in blood glucose level induced by angiotensin II appears to be mediated by facilitation of catecholamine release or due to inhibition of reuptake.