Remifentanil as analgesia for labor.

BACKGROUND AND OBJECTIVES: The neuraxial techniques currently represent the most effective methods for pain control during labor and the epidural block using ultradiluted anesthetic solutions is considered the gold standard promoting adequate pain relief with minimum side effects. In some situations however the use of these techniques is limited by the existence of maternal contraindications, or structural or material obstacles. In these cases, the alternatives are still precarious and scarce offering little optimistic results and of dubious effectiveness. CONTENT: This article presents through a literature review the available information on the use of remifentanil as an alternative technique for analgesia during labor discussing aspects of pharmacokinetics, analgesia efficacy, maternal satisfaction and maternal/fetal side effects. CONCLUSIONS: The initial data show that remifentanil is a promising option to be employed in situations where the parturient cannot or does not want to receive the neuraxial analgesia.

Remifentanil em analgesia para o trabalho de parto: [revisão] / Remifentanil en analgesia para el trabajo de parto: [revisión] / Remifentanil as analgesia for labor

JUSTIFICATIVA E OBJETIVOS: As técnicas neuroaxiais representam atualmente os métodos mais efetivos para controle da dor durante o trabalho de parto e a analgesia peridural utilizando soluções anestésicas ultradiluídas é considerada o padrão ouro, promovendo alívio adequado da dor com mínimos efeitos colaterais. Em algumas situações, no entanto, o emprego dessas técnicas é limitado pela existência de contraindicações maternas ou obstáculos estruturais e materiais. Nestes casos, as opções alternativas ainda são precárias e escassas, oferecendo resultados pouco otimistas e de eficácia questionável. CONTEÚDO: Este artigo apresenta, com base em uma revisão da literatura, as informações disponíveis relacionadas ao emprego do remifentanil como técnica alternativa para a analgesia de parto discutindo aspectos farmacocinéticos, farmacodinâmicos, eficácia analgésica, satisfação materna e efeitos colaterais maternos e fetais. CONCLUSÕES: Os dados iniciais apontam o remifentanil como uma opção promissora a ser empregada nas situações em que a gestante não quer ou não pode receber a analgesia neuroaxial.

BACKGROUND AND OBJECTIVES: The neuraxial techniques currently represent the most effective methods for pain control during labor and the epidural block using ultradiluted anesthetic solutions is considered the gold standard promoting adequate pain relief with minimum side effects. In some situations however the use of these techniques is limited by the existence of maternal contraindications, or structural or material obstacles. In these cases, the alternatives are still precarious and scarce offering little optimistic results and of dubious effectiveness. CONTENT: This article presents through a literature review the available information on the use of remifentanil as an alternative technique for analgesia during labor discussing aspects of pharmacokinetics, analgesia efficacy, maternal satisfaction and maternal/fetal side effects. CONCLUSIONS: The initial data show that remifentanil is a promising option to be employed in situations where the parturient cannot or does not want to receive the neuraxial analgesia.

JUSTIFICATIVA Y OBJETIVOS: Las técnicas neuroaxiales representan actualmente los métodos más efectivos para el control del dolor durante el trabajo de parto, y la analgesia epidural utilizando soluciones anestésicas ultradiluidas se considera el estándar oro, promoviendo el alivio correcto del dolor con los mínimos efectos colaterales. En algunas situaciones, sin embargo, el uso de esas técnicas queda limitado por la existencia de contraindicaciones maternas u obstáculos estructurales y materiales. En esos casos, las alternativas todavía son precarias y escasas, ofreciendo resultados poco optimistas y de una eficacia cuestionable. CONTENIDO: Con base en una revisión de la literatura, este artículo muestra que las informaciones disponibles relacionadas a lo empleo de lo remifetanil como técnica alternativa para la analgesia del parto discutindo los aspectos farmacocinéticos, farmacodinamicos, eficacia analgésica, satisfacion materna y efectos colaterales maternos y fetales. CONCLUSIONES: Los datos iniciales nos indican al remifentanil como una opción promisoria que podemos usar en las situaciones en que la embarazada no quiere o no puede recibir la analgesia neuroaxial.

Cerebral DARPP-32 expression after methylphenidate administration in young and adult rats.

Dopamine may alter the phosphorylation state of DARPP-32 that plays a central role in the dopaminergic neurons biology. Studies have shown that DARPP-32/protein phosphatase 1 cascade is a major target for psychostimulants drugs. Methylphenidate is a psychostimulant that acts blocking the dopamine transporter has been used as an effective treatment for Attention Deficit Hyperactivity Disorder. We investigated if methylphenidate could alter DARPP-32 expression in five brain regions (striatum, hippocampus, prefrontal cortex, cortex and cerebellum) in young and adult rats. Our results showed that methylphenidate treatment is able to alter DARPP-32 expression in rat brain. Acute methylphenidate treatment has reduced hippocampal DARPP-32 protein levels in old rats, while chronic methylphenidate treatment has decreased them in old rat hippocampus and young rat cerebellum. It was found an increased cortical expression after chronic methylphenidate administration in old rats. Our results provide the first experimental demonstration that methylphenidate induces changes in total DARPP-32 expression that are posology- and age-related in some rat brain areas, although further studies are needed to shed more light on the mechanisms behind these findings.

Methylphenidate alters NCS-1 expression in rat brain.

Methylphenidate has been used as an effective treatment for attention deficit hyperactivity disorder (ADHD). Methylphenidate (MPH) blocks dopamine and norepinephrine transporters causing an increase in extracellular levels. The use of psychomotor stimulants continues to rise due to both the treatment of ADHD and illicit abuse. Methylphenidate sensitization mechanism has still poor knowledge. Neuronal calcium sensor 1 was identified as a dopaminergic receptor interacting protein. When expressed in mammalian cells, neuronal calcium sensor 1 attenuates dopamine-induced D2 receptor internalization by a mechanism that involves a reduction in D2 receptor phosphorylation. Neuronal calcium sensor 1 appears to play a pivotal role in regulating D2 receptor function, it will be important to determine if there are alterations in neuronal calcium sensor 1 in neuropathologies associated with deregulation in dopaminergic signaling. Then, we investigated if methylphenidate could alter neuronal calcium sensor 1 expression in five brain regions (striatum, hippocampus, prefrontal cortex, cortex and cerebellum) in young and adult rats. These regions were chosen because some are located in brain circuits related with attention deficit hyperactivity disorder. Our results showed changes in neuronal calcium sensor 1 expression in hippocampus, prefrontal cortex and cerebellum mainly in adult rats. The demonstration that methylphenidate induces changes in neuronal calcium sensor 1 levels in rat brain may help to understand sensitization mechanisms as well as methylphenidate therapeutic effects to improve attention deficit hyperactivity disorder symptoms.