Latin American consensus on guidelines for chronic migraine treatment / Consenso latino-americano para as diretrizes de tratamento da migranea cronica

Chronic migraine is a condition with significant prevalence all around the world and high socioeconomic impact, and its handling has been challenging neurologists. Developments for understanding its mechanisms and associated conditions, as well as that of new therapies, have been quick and important, a fact which has motivated the Latin American and Brazilian Headache Societies to prepare the present consensus. The treatment of chronic migraine should always be preceded by a careful diagnosis review; the detection of possible worsening factors and associated conditions; the stratification of seriousness/impossibility to treat; and monitoring establishment, with a pain diary. The present consensus deals with pharmacological and nonpharmacological forms of treatment to be used in chronic migraine.

A migrânea crônica é uma condição com prevalência significativa ao redor do mundo e alto impacto socioeconômico, sendo que seu manuseio tem desafiado os neurologistas. Os avanços na compreensão de seus mecanismos e das condições a ela associadas, bem como nas novas terapêuticas, têm sido rápidos e importantes, fato que motivou as Sociedades Latino-americana e Brasileira de Cefaleia a elaborarem o presente consenso. O tratamento da migrânea crônica deve ser sempre precedido por uma revisão cuidadosa do diagnóstico, pela detecção de possíveis fatores de piora e das condições associadas, pela estratificação de gravidade/impossibilidade de se tratar e pelo monitoramento com um diário da dor. Este consenso apresenta abordagens farmacológicas e não-farmacológicas para tratar a migrânea crônica.

Direct negative chronotropic and inotropic efects of curare on isolated and perfused frog's heart

It has been stated that curare has no direct effect upon the heart because the cardiac muscle is deprived of nicotine receptors. While performing an experimental work, we noticed that when high doses of curare were administered to frogs, a change in cardiac activity occurred. In order to elucidate whether the cardiac effects of curare wee the results of a direct action or a reflex response, we studie the effects of increasing doses of d-tubocurarine on the rate and contractility of 8 isolated and perfused frogs'hearts. After testing the d-tubocurarine effects on the heart rate and contractility, we added either acetylcholine, atropine, atenonol or verapamil in orden to find out whether any change ocurred in the cardiac effects produced byd-tubocurarine. Thirty seven measurements were carriet out and it wasfound that 1) high doses (between 1 and 15 micrograms) of d-tubocurarine produced a highly significant decrease in heart rate an contractility; 2) d-tubocurarine did not avoid the acetycholine effect; 3) atropine, atenonol and verapamil did not interfere with d-tubocurarine effects. We conclude that high doses of d-tubocurarine produce "dosis-dependent" heart rate and contratility reductions. These effects are not mediated by muscarinic receptors beta-1 receptors or the show calcium channels