Dopamine receptors gene expression in male rat hippocampus after administration of MDMA (ecstasy) / La expresión génica de receptores de dopamina en el hipocampo de ratas macho después de la administración de MDMA (éxtasis)

Ecstasy is one of the most popular amusing drugs among young people. Documents indicate some effects of Ecstasy on hippocampus and close relations between dopaminergic functions with reward learning. Therefore, the aim of this study was evaluation of the chronic effects of Ecstasy on memory in male Wistar rats and determination of dopamine receptors' gene expression in hippocampus. Forty adult male Wistar rats randomly distributed in five groups: Control, sham (received 1 ml/kg 0.9% saline) and three experimental groups were: Exp. 1 (2.5 mg/kg), Exp. 2 (5 mg/kg), and Exp. 3 (10 mg/kg) received MDMA intraperitoneally once every 7 days (3 times a day, 3 hours apart) for 4 weeks. Before the first injection animals trained in Shuttle Box memory and tested after the last injection. 24 hours after the final testing, brains of rats were dissected and hippocampus was removed and homogenized. After total RNA extraction and cDNA synthesis, expression of dopamine receptor genes in the hippocampus determined with Real-Time PCR. Our results showed that 2.5 and 5 mg/kg MDMA-treated groups had memory impairment. Also we found that MDMA increased the mRNA expression of dopamine receptors in hippocampus and the highest increase found in dopamine D1 receptors in the 5 mg/kg experimental group. We concluded that low doses of Ecstasy could increase Dopamine takers gene expression in hippocampus and disorder avoidance memory. But in high doses the increase in Dopamine takers gene expression was not as much as that in low doses and avoidance memory disorder was not observed.

El éxtasis es una de las drogas de diversión más populares entre los jóvenes. La investigación reporta algunos de los efectos del éxtasis sobre el hipocampo y la relación entre las funciones dopaminérgicas con la recompensa en el aprendizaje. El objetivo de este estudio fue la evaluación de los efectos crónicos del éxtasis en la memoria de ratas macho Wistar y la determinación de la expresión de genes receptores de dopamina en el hipocampo. Cuarenta ratas macho adultas fueron distribuidas al azar en cinco grupos: grupo control, simulado (a 1 ml/kg 0,9% de solución salina) y tres grupos experimentales: Grupo exp. 1 (2,5 mg/kg), Exp. 2 (5 mg/kg), y Exp. 3 (10 mg/kg) recibió MDMA vía intraperitoneal cada 7 días (3 veces al día, con 3 horas de diferencia) durante 4 semanas. Antes de la primera inyección los animales fueron entrenados en memoria Shuttle Box y examinados después de la última inyección. Veinticuatro horas después de la prueba final, los cerebros de las ratas fueron diseccionados, el hipocampo fue separado y homogeneizado. Después de la extracción total de ARN y síntesis de ADNc, la expresión de genes de los receptores de dopamina en el hipocampo fue determinado con PCR en tiempo real. Nuestros resultados mostraron que los grupos de 2,5 kg y 5 mg/MDMA tratados tenían deterioro de la memoria. Además, encontramos que la MDMA aumentó la expresión de ARNm de los receptores de dopamina en el hipocampo y el aumento mayor se observó en los receptores D1 de dopamina en el 5 mg/kg Grupo experimental. En conclusión, las dosis bajas de éxtasis podrían aumentar tomadores de expresión génica de la dopamina en el hipocampo y trastornos de la memoria. Sin embargo, en dosis altas el aumento de la expresión génica no mostró un aumento significativo, a diferencia de los resultados con dosis bajas, tampoco se observaron trastornos disociativos de memoria.

effects of different concentrations of leukemia inhibitory factor on the development of isolated preantral follicles from fresh and vitrified mouse ovaries

Leukemia inhibitory factor [LIF] is a pleiotropic cytokine of interleukin-6 family with a remarkable range of biological actions such as proliferative effects on the granulosa and theca cells. The aim of this study was to evaluate the effects of LIF on the growth and maturation of mouse fresh and vitrified preantral follicles, an in vitro model was developed. The ovaries of 14-day-old mice were vitrified in a mixture of ethylene glycol, ficoll 70 and sucrose in PB1 for 5 min. The preantral follicles were mechanically isolated from vitrified-warmed and non-vitrified ovaries. They were cultured in alpha-minimum essential medium supplemented with 5% fetal bovine serum, 100 mIU/ml recombinant follicle stimulating hormone, 1% insulin, transferrin and selenium, 20 ng/ml murine recombinant epidermal growth factor and different concentrations of LIF [25, 50, 100 ng/ml] for 12 days. On day 12, ovulation was induced using 1.5 mIU/ml human chorionic gonadotropin. In this study, the follicle diameter, survival rate and maturation rate were assessed. The mean diameter of fresh and vitrified preantral follicles cultured in 50 ng/ml concentration of murine recombinant LIF was significantly higher than that of other concentrations in each group on day 2 [229.42 +/- 30.40, 222.55 +/- 33.4] [P<.001] and on day 4 [340.45 +/- 61.05, 299.50 +/- 65.55], respectively [P<0.01]. The survival rates of follicle in fresh and vitrified groups were 80.56% and 77.78, respectively. There was no significant difference between control and treated groups. The percentage of follicles which released metaphase II [MII] oocyte in fresh groups in the presence of 0, 25, 50, 100 ng/ml of LIF was 16%, 14.28%, 40% and 21.05% [P<0.01] and so in vitrified groups were 11.76%, 14.28%, 28.57% and 13.38%, respectively [P<0.05]. There were significant differences between 50 ng/ml LIF-treated groups with other concentrations in each group. Therefore, in vitro growth and maturation of mouse follicles were improved in the presence of 50 ng/ml LIF