Efeito relaxante do extrato aquoso das folhas de Erythrina vellutina em ducto deferente de rato

O objetivo deste trabalho foi avaliar o efeito do extrato aquoso das folhas de Erythrina vellutina (AE) sobre ducto deferente de rato. Nesta preparação, o AE inibiu as contrações induzidas por estímulo elétrico de campo de maneira dependente da concentração. Esta inibição não foi afetada após atropina (10-5M), propanolol (10-5M), prazosin (10-5M) ou yohimbina (10-5M), sugerindo uma ação indireta do AE sobre receptores colinérgicos ou adrenérgicos. A incubação da preparação com os antagonistas de canais de K+, tetraetilâmonio (10-6M) ou 4-aminopiridina (10-6M) não alterou o efeito inibitório induzido pelo AE. Entretanto, a glibenclamida (10-6M) atenuou significantemente este efeito, sugerindo um possível envolvimento de canais de K+ dependentes de ATP. Além disso, o AE (0.15 mg/mL) não alterou as contrações induzidas por noradrenalina (10-5M), ATP (10-4M) ou KCl (80 mM), descartando uma interação do AE com um sítio pós-sináptico. Em conclusão, estes resultados demonstram que o efeito inibitório do AE pode ser devido a uma interação pré-sináptica com canais de K+ dependentes de ATP em neurônios simpáticos de ducto deferente de rato. _________________________________________________________________________________________ ABSTRACT: The effect of the Aqueous Extract from the leaves of Erythrina vellutina (AE) on rat vas deferens preparation was evaluated in this work. The AE inhibited the muscle contractions induced by electrical field stimulation (EFS) in a concentration-dependent manner. This inhibition was not affected by atropine (10-5M), propanolol (10-5M), prazosin (10-5M) or yohimbine (10-5M), suggesting that there is no direct interaction of the AE with cholinergic nor adrenergic receptors. Incubation of vas deferens with the K+ channel antagonists, tetraethylamonium (10-6M) or 4-aminopyridine (10-6M) had also no effect on the AE-induced inhibition. On the other hand, glibenclamide (10-6) significantly attenuated the effect of the AE, suggesting a possible involvement of ATP-dependent K+ channels. The AE (0.15 mg/mL) did not alter the contractions induced by noradrenaline (10-5M), ATP (10-4M) nor KCl (80 mM), against an interaction of the extract with post-synaptic sites. The data presented suggests that the inhibition of the electrically driven muscle twitches by the AE could be due to a pre-synaptic interaction of the extract with ATP-dependent K+ channels from vas deferens sympathetic neurons

El efecto anticonvulsivo de geraniol y la inclusión de geraniol complejo: β-ciclodextrina

Geraniol (GR) es un alcohol monoterpeno acíclico presentes en los aceites esenciales de las especies de plantas aromáticas utilizadas en la medicina popular brasileña para el tratamiento de la epilepsia. El presente estudio fue diseñado para evaluar el efecto anticonvulsivo del GR y de la inclusión de geraniol complejo: β-ciclodextrina (GR:β-CD). Los ratones fueron tratados con GR o con GR:β- CD (50, 100 y 200 mg/kg) 30 minutos antes de pentylenotetrazole (PTZ) o strichinine (STN). GR a 200 mg/kg y GR:β-CD en las dosis de 100 y 200 mg/kg aumentó significativamente la latencia para la primera convulsión inducida PTZ-y redujo la porcentaje de animales que convulsionó. El tratamiento previo de flumazenil no revirtió el efecto anticonvulsivo de GR en el modelo de convulsión inducida con PTZ. En el modelo de convulsión inducida com STN, los efectos de GR fueron investigados y no se encontró ninguna diferencia contra el control. Los resultados demostraron una actividad anticonvulsiva de geraniol en el modelo de PTZ, que fue potenciada por la formación de complejos con β-CD

Attenuation of motor deficits by hydroethanolic extract of Poincianella pyramidalis in a Parkinson's disease model

The present study aimed to evaluate the possible neuroprotective effect of the hydroethanolic extract of Poincianella pyramidalis (EFIPp) (Tul.) L. P. Queiroz (Fabaceae), an endemic plant found in Northeastern Brazil, commonly used in folk medicine, on the motor deficits induced by repeated treatment with reserpine (RES) in rats. Adult male Wistar rats received 10 s.c. injections of 0.1 mg/kg RES or vehicle (VR), every 48 h, and daily i.p. injections daily of HEPp (25 mg/kg) or vehicle (VE). Throughout treatment, catalepsy behavior and oral movements were scored. After behavioral tests, superoxide dismutase (SOD) and catalase (CAT) activities were evaluated in the prefrontal cortex, hippocampus and striatum. RES treatment induced a progressive increase of catalepsy time in the treated group compared to control groups starting at day 15. RES also increased the number of vacuous chewing movements, tongue protrusions and duration of facial twitching. Treatment with HEPp attenuated the motor deficit in the catalepsy test and delayed the onset of oral movements induced by RES. No significant changes were observed in the antioxidant assay. Taken together, these results show a beneficial effect of HEPp on motor deficits induced by reserpine, suggesting a neuroprotective effect in a rat model of PD.Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Fundação de Apoio a Pesquisa e a Inovação Tecnologica do Estado de Sergipe (FAPITEC)Pro-reitoria de Pesquisa da Universidade Federal de Sergipe (POSGRAP/UFS)Univ Fed Sergipe, Dept Physiol, Sao Cristovao, SE, BrazilUniv Massachusetts, Neurosci & Behav Program, Amherst, MA 01003 USAMinist Educ, CAPES Fdn, BR-70040020 Brasilia, DF, BrazilUniv Fed Sao Paulo, Dept Biosci, Santos, SP, BrazilUniv Fed Sao Paulo, Dept Pharmacol, Sao Paulo, SP, BrazilUniv Fed Sergipe, Dept Biosci, Itabaiana, SE, BrazilUniv Fed Sao Paulo, Dept Biosci, Santos, SP, BrazilUniv Fed Sao Paulo, Dept Pharmacol, Sao Paulo, SP, BrazilWeb of Scienc

Attenuation of motor deficits by hydroethanolic extract of Poincianella pyramidalis in a Parkinson’s disease model

The present study aimed to evaluate the possible neuroprotective effect of the hydroethanolic extract of Poincianella pyramidalis (EHPp) (Tul.) L. P. Queiroz (Fabaceae), an endemic plant found in Northeastern Brazil, commonly used in folk medicine, on the motor deficits induced by repeated treatment with reserpine (RES) in rats. Adult male Wistar rats received 10 s.c. injections of 0.1 mg/kg RES or vehicle (VR), every 48 h, and daily i.p. injections daily of HEPp (25 mg/kg) or vehicle (VE). Throughout treatment, catalepsy behavior and oral movements were scored. After behavioral tests, superoxide dismutase (SOD) and catalase (CAT) activities were evaluated in the prefrontal cortex, hippocampus and striatum. RES treatment induced a progressive increase of catalepsy time in the treated group compared to control groups starting at day 15. RES also increased the number of vacuous chewing movements, tongue protrusions and duration of facial twitching. Treatment with HEPp attenuated the motor deficit in the catalepsy test and delayed the onset of oral movements induced by RES. No significant changes were observed in the antioxidant assay. Taken together, these results show a beneficial effect of HEPp on motor deficits induced by reserpine, suggesting a neuroprotective effect in a rat model of PD

Essential Oil of Ocimum basilicum

The racemate linalool and its levogyrus enantiomer [(−)-LIN] are present in many essential oils and possess several pharmacological activities, such as antinociceptive and anti-inflammatory. In this work, the effects of essential oil obtained from the cultivation of the Ocimum basilicum L. (EOOb) derived from Germplasm Bank rich in (−)-LIN content in the excitability of peripheral nervous system were studied. We used rat sciatic nerve to investigate the EOOb and (−)-LIN effects on neuron excitability and the extracellular recording technique was used to register the compound action potential (CAP). EOOb and (−)-LIN blocked the CAP in a concentration-dependent way and these effects were reversible after washout. EOOb blocked positive amplitude of 1st and 2nd CAP components with IC50 of 0.38±0.2 and 0.17±0.0 mg/mL, respectively. For (−)-LIN, these values were 0.23±0.0 and 0.13±0.0 mg/mL. Both components reduced the conduction velocity of CAP and the 2nd component seems to be more affected than the 1st component. In conclusion EOOb and (−)-LIN inhibited the excitability of peripheral nervous system in a similar way and potency, revealing that the effects of EOOb on excitability are due to the presence of (−)-LIN in the essential oil