RESUMO
In this issue, Rodrigues et al. (2020) present a systematic review with meta-analyses that reports the efficacy of five treatments for children with attention-deficit hyperactivity disorder symptoms in the context of autism spectrum disorder - (a) methylphenidate; (b) atomoxetine; (c) guanfacine; (d) aripiprazole; and (e) risperidone. In this commentary, we highlight the contrast between the scarce evidence base of treatment for ADHD in the context of autism and other subpopulations, such as tic disorders and intellectual disability, and the extensive evidence base of treatment for ADHD in general. The commentary weighs about the conundrum clinicians face of whether to rely on the limited evidence base of treatment for ADHD in subpopulation, or to derive conclusions from the larger body of evidence of treatment for ADHD in general. The commentary also discusses potential avenues for future research to address this clinical problem.
Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Metilfenidato , Cloridrato de Atomoxetina/farmacologia , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Espectro Autista/tratamento farmacológico , Criança , Guanfacina/farmacologia , Humanos , Metilfenidato/farmacologiaRESUMO
We investigated the effects of epinephrine on the reversible nerve conduction block induced by high [K(+)](o) using electrophysiological extracellular recordings in the isolated rat sciatic nerve in vitro. Bath application of 400 micro M epinephrine (EN) or norepinephrine (NE) reduced the high-potassium-induced compound action potentials (CAPs) blockage in both sensory and motor fibers. The beta-adrenoreceptor agonist isoproterenol mimicked the EN effect while the alpha-adrenoreceptor agonists phenylephrine and guanfacine did not affect the CAPs reduction. Addition of EN to normal ACSF partially reversed the nerve conduction blockage induced by high frequency stimulation. These results suggest that EN and NE modulate the electrophysiological properties of both sensory and motor axons, and they improve the nerve conduction under high [K(+)](o) by modulating nerve excitability.