Análisis de impacto presupuestal del uso de anticuerpos bloqueadores de acetilcolina receptores, comparado con la prueba de Tensilon, de estímulo repetitivo, electromiografía con electrodo de fibra única e I CE test para pacientes con miastenia gravis / Budget impact analysis of the use of acetylcholine receptor blocking antibodies, compared to the Tensilon test, repetitive stimulus, electromyography with single fiber electrode and IEC test for patients with myasthenia gravis

Tecnologías evaluadas: -Tecnologías actuales: electromiografía con electrodo de fibra única e ICE test;\r\n-Tecnología nueva: anticuerpos bloqueadores de acetilcolina receptores, prueba de Tensilon, prueba de estímulo repetitivo. Población: Esta prueba se puede aplicar a todas las edades y a todos los sexos, ya que la aparición de la enfermedad puede presentarse en toda la población. Perspectiva: Tercer pagador - Sistema General de Seguridad en Salud (SGSSS) colombiano. Horizonte temporal: El horizonte temporal de este AIP en el caso base corresponde a un año. Adicionalmente se reportan las estimaciones del impacto presupuestal para los años 2 y 3, bajo el supuesto de la inclusión en el POS en el año 1. Costos incluidos: Solo se tuvieron en cuenta los costos de las pruebas: -Electromiografía con electrodo de fibra única: $71.262,1; -Ice test: $26.223,3; Prueba completa de Tensilon: $24.000; -Prueba de estímulo repetitivo: $46.219,1; -Test de anticuerpos contra receptor de acetilcolina por RIA (ACRA): $45.416. Fuente de costos: Para todas las pruebas diagnósticas se utilizó el promedio ponderado estimado desde los registros de uso de servicios de 2014 SISPRO (módulo de prestación de servicios, mediante conexión OBDS), teniendo como corte de búsqueda la fecha del desarrollo de este impacto (20/10/2015). Todos los costos de las pruebas son ponderados por el número de unidades utilizadas que reporta la misma base de datos. Además, todas\r\nlas tecnologías son costeadas desde bases de aseguradores, para confirmación de precios. Resultados: Actualmente, el mercado se encuentra dominado por la electromiografía con electrodo de fibra única, la cual se encuentra dentro del plan de beneficios, pero por opinión de los realizadores, una vez que la prueba de acetilcolina receptores y de Lambert entre al plan de beneficios, se aumentará su participación, lo cual repercutirá en un ahorro al sistema, dado que dichas pruebas son menos costosas.(AU)

Insulin replacement restores the vesicular secretory apparatus in the diabetic rat lacrimal gland / Reposição de insulina restaura o mecanismo secretório da glândula lacrimal de ratos diabéticos

ABSTRACT Purpose: In the lacrimal gland (LG) acinar cells, signaling regulates the release of secretory vesicles through specific Rab and SNARE exocytotic proteins. In diabetes mellitus (DM), the LGs are dysfunctional. The aim of this work was to determine if secretory apparatus changes were associated with any effects on the secretory vesicles (SV) in diabetic rats as well as the expression levels of constituent Rab and members of the SNARE family, and if insulin supplementation reversed those changes. Methods: DM was induced in male Wistar rats with an intravenous dose of streptozotocin (60 mg/kg). One of the two diabetic groups was then treated every other day with insulin (1 IU). A third control group was injected with vehicle. After 10 weeks, Western blotting and RT-PCR were used to compared the Rab and SNARE secretory factor levels in the LGs. Transmission electron microscopy evaluated acinar cell SV density and integrity. Results: In the diabetes mellitus group, there were fewer and enlarged SV. The Rab 27b, Rab 3d, and syntaxin-1 protein expression declined in the rats with diabetes mellitus. Insulin treatment restored the SV density and the Rab 27b and syntaxin expression to their control protein levels, whereas the Vamp 2 mRNA expression increased above the control levels. Conclusions: Diabetes mellitus LG changes were associated with the declines in protein expression levels that were involved in supporting exocytosis and vesicular formation. They were partially reversed by insulin replacement therapy. These findings may help to improve therapeutic management of dry eye in diabetes mellitus. .

RESUMO Objetivo: Células acinares da glândula lacrimal (GL) sinalizam a regulação da liberação através de vesículas secretórias específicas Rab proteínas exocitóticas SNARE. No diabetes mellitus (DM), as glândulas lacrimais são disfuncionais. O objetivo deste trabalho foi determinar se em ratos diabéticos, alterações dos aparatos secretórios estão associados a efeitos sobre vesículas secretoras (VS) e sobre os níveis de expressão do constituinte Rab, bem como membros da família SNARE, e se a suplementação de insulina reverte as alterações. Métodos: DM foi induzido em ratos Wistar machos com uma dose intravenosa de estreptozotocina (60 mg/kg). Um dos dois grupos diabéticos foi então tratado a cada dois dias com insulina (1 UI). Um terceiro grupo controle foi injetado com o veículo. Após 10 semanas, western blot e RT-PCR comparou níveis de fatores secretórios de Rab e SNARE na glândula lacrimal. Microscopia eletrônica de transmissão (MET) avaliaram a densidade e integridade de VS de célula acinar. Resultados: No grupo diabetes mellitus , houve poucas e alargadas VS. Rab27b, Rab 3d e Sintaxina-1 diminuiu a expressão da proteína em ratos com Diabetes Mellitus. O tratamento com insulina restaurou a densidade das VS e expressão de Rab 27b e Sintaxina para seus níveis de proteína controle, enquanto a expressão de Vamp 2 RNAm aumentou em relação aos controles. Conclusões: Alterações na glândula lacrimal de diabetes mellitus estão associadas a reduções nos níveis de expressão de proteínas envolvidas no apoio a exocitose e formação vesicular. Eles são, em parte, revertida por terapia de reposição de insulina. Estes resultados podem ajudar a melhorar a conduta terapêutica do olho seco no diabetes mellitus. .

Influencia de mecanismos colinergicos nos processos neurodegenerativos relacionados a formacao de amiloide e a fosforilacao da proteina TAU / Cholinergic mechanisms influence in neurodegenerative process related to amyloid formation and phosphorylation of TAU protein

Na doenca de Alzheimer (DA), os principais eventos associados a neurodegeneracao sao a formacao de placas senis e de emaranhados neurofibrilares. Estes fenomenos relacionam-se respectivamente a deposicao de beta-amiloide (Ab) e a alteracoes do estado de fosforilacao da proteina Tau. Esta e componente essencial dos microtubulos, onde se encontra em estado polimerizado. A estabilidade do polimero depende do grau de fosforilacao da Tau, tornando-se mais instavel quanto mais fosforilada a proteina. Consequentemente, a hiperfosforilacao da Tau relaciona-se com menor estabilidade do citoesqueleto, favorecendo a morte neuronal. O Ab e produzido pela clivagem da proteina precursora do amiloide (APP) por acao da enzima beta-secretase, em detrimento da acao mais fisiologica da alfa-secretase, que da origem ao fragmento APPs. As fibras de Ab tem diversos efeitos neurotoxicos, alem de ocorrerem associadamente a uma presumivel perda funcional do metabolito secretado APPs...

La desestabilización del receptor nicotínico para la acetilcolina / Desensitization of the nicotinic acetylcholine receptor

Los canales iónicos actúan acelerando el movimiento de los iones a través de las membranas biológicas. Cada canal iónico se activa por un estímulo específico (p. ej. eléctrico, mecánico, químico, etc.). Los receptores de membrana que actúan como canales iónicos (RMCI), pueden pasar a un estado denominado desensibilizado, cuando el agonista se encuentra ligado al receptor. El estado desensibilizado de un RMCI, como por ejemplo, el receptor nicotínico para la acetilcolina (nAChR), es un estado no funcional del canal y es un caso particular del denominado agotamiento de receptores "receptors rundown". La desensibilización de los RCMI sólo involucra una reducción de su actividad y no de su eliminación de la membrana. La desensibilización es importante en el control de la transmisión sináptica y en el desarrollo del sistema nervioso. En esta revisión se discuten los resultados más relevantes relacionados a su caracterización y modulación, de igual manera, algunos aspectos relacionados con los principales modelos cinéticos que le han tomado en consideración. Finalmente, se plantea la utilización de nuevas técnicas de biología molecular y electrofisiología para el estudio de la desensibilización y su importancia en los sistemas biológicos

Método bioquímico para la determinación de acetil colinesterasa modificada, que confiere resistencia cruzada a insecticidas organofosforados y carbomatos en Culex quinquefasciatus Say, 1823 / Biochemical method to determine the altered acetylcholinesterase which confers cross resistance to organophosphate and carbomate insecticides in Culex quinquefasciatus Say, 1823

Se realizó el montaje de un método rápido para la determinación de la frecuencia del gen de la acetil colinesterasa modificada, que confiere resistencia cruzada a insecticidas organofosforados y carbomatos en mosquitos. Para el montaje de la técnica se utilizaron cepas de laboratorio de Culex quinquefasciatus Say, 1823. Se obtuvo una buena diferenciación en los valores de absorvancia entre los mosquitos homocigóticos susceptibles (SS), heterocigóticos (RS) y homocigóticos (RR) resistentes con valores de actividad enzimatica residual de 10-60, 70-100 y 80-120, respectivamente, lo que además se pudo diferenciar a simple vista basado en el cambio de color amarillo en la reacción. Se encontró el gen de la acetil colinesterasa modificada en las cepas de Culex quinquefasciatus estudiadas

Methyl parathion induced alterations in GABAergic system during critical stage of central nervous system development in albino rat pups.

Sublethal doses of methyl parathion (o, o-dimethyl-o-nitrophenyl thiophosphate) injected intraperitoneally to 7th day old developing albino rat pups induced alterations in the inhibitory GABAergic system of CNS. A substantial simulation of the inhibitory system was noticed. A profound increase was found in the level of the inhibitory transmitter, GABA on methyl parathion injection. An increase in the activity levels of the enzymes glutamic acid decarboxylase and 4-aminobutyrate-2-oxoglutarate-amino transferase in the cortex, brain stem and spinal cord of the CNS was found. It is observed that methyl parathion causes potentiation of the inhibitory transmission (GABAergic system) in the wake of inducing suppression of cholinergic system in CNS of developing rat pups.

Rapidly recurring cortical seizures induce changes in neuronal responsiveness to acetylcholine

La mayoría de los mecanismos propuestos para explicar la descarga epiléptica sugieren un excesivo influjo sináptico o posibles cambios en la excitabilidad celular que resultan en una disminución del umbral conculsivo y en la presencia de actividad autosostenida. Es probable que estos cambios sean causados por modificaciones en la sensibilidad de los receptores de membrana a un neurotransmisor específico. En vista de lo anterior, el objetivo del presente estudio ha sido evaluar la sensibilidad del receptor postsináptico por medio de la aplicación microiontoforética de sustancias cuyo efecto farmacológico es bien conocido, para determinar su posible participación en el proceso epiléptico. Se provocaron cambios en la excitabilidad cortical por estimulación eléctrica en la corteza sensoriomotora de ratas anestesiadas con uretano (1 g/kg intraperitoneal), inmovilizadas con bromuro de pancuronio y mantenidas con respiración mecánica. Los estímulos eléctricos consistieron en trenes de pulsos bifásicos, cada uno con duración de un milisegundo con frecuencia de 100 pps y con duración del tren de 1 segundo. La respuesta de la neurona a la acetilcolina fue evaluada antes y después que se establecieron las descargas. La dosis se midió en monoampres de corriente microiontoforética. Los potenciales del campo extracelular se registraron con el barril central de micropipetas. Los barriles periféricos fueron usados para aplicaciones iontoforéticas de acetilcolina (Ach .1, 1M), atropina (25 mM). Uno de estos barriles conteniendo NaCl (2M) se empleó para el paso automático de corriente de balance; para 613 de estas células las descargas ya estaban establecidas; en las restantes 532 células, la corteza fue normal (sin descargas). Un aumento en la frecuencia promedio de descarga celular se obsevó después de la aplicación iontoforética de Ach. Intensidades de 2 a 50 nA de corriente se emplearon en la corteza con descargas establecidas. En la corteza con descargas no establecidad la respuesta celular a la aplicación de Ach fue menor cuando fueron aplicadas corrientes de igual intensidad. En ambas cortezas, las células respondieron con mucha menor intensidad a la aplicación de NaCl con corriente de magnitud similar a la usada para movilizar la Ach. Estos hallazgos muestran un cambio en la excitabilidad celualr que se refleja en un nivel más elevado de respuesta celular cuando la acetilcolina está presente, y sugieren que este neurotransmisor participa en el mecanismo de la epilep

Use of rat jejunum for assay of acetylcholine.

Experiments were carried out to determine the advantage in using isolated rat jejunum in the assay of acetylcholine (ACh) in preference to other tissues. Rat jejunum was found to be sensitive to ACh 0.01 micrograms, 5-hydroxytryptamine (5HT) 0.2 to 0.5 microgram and least sensitive to histamine. (Ach greater than 5HT greater than histamine).

Cholinergic components in human gingiva in healthy and inflamed states.

Acetylcholine (ACh) and acetylcholinesterase (AChE) are main components in cholinergic nervous system. ACh is a natural constituent of many parts of the nervous system and its chief role is neurotransmission. It is not entirely unique in function to the cholinergic tissues of the human body. Gingiva is the part of the oral mucosa which contains numerous mast cells. They contain a variety of biologically active substances including neurotransmitters such as 5-hydroxytryptamine, histamine etc. In the dental literature accessible to authors no data were found on ACh and AChE in the different oral structures in health and inflamed conditions. Therefore gingiva samples from 50 human individuals representing varying grades of inflammatory involvement have been utilised in the present study. ACh and AChE were estimated in the gingiva tissues by flurometric and spectrophotometric methods. This study established hithero unknown "norms" for the ACh and AChE contents of the clinically normal gingiva, which are found to be 0.85 +/- 0.06(SE) ug/g and 210 +/- 18(SE) micromoles ACh hydrolysed/hr/gm/wet tissues. Results also revealed that the range of variations of ACh is high and AChE is low in all the inflamed states of gingival tissues.

Gastric acetylcholine and histamine content of normal and Trypanosoma cruzi - infected rats

The consequences of acute Trypanosoma cruzi infection for acetylcholine and histamine levels in gastric wall and for mast cells of the stomach were studied in rats. Intraperitoneal infection with 4,000 trypomastigotes/g of a Y strain of Trypanosoma cruzi led to a 4-fold decrease in gastric acetylcholine level and to a 57 - and 15-fold increase in histamine content in the membranous and glandular regions of the rat stomach, respectively. Infection of rats with Trypanosoma cruzi also induced a 2- and 4-fold increase in mast cell numbers in the membranous and glandular regions of the muscle layer of the gastric wall, respectively, and a ganglionic inflammatory reaction with predominance of mononuclear cells. We conclude that in acutely Trypanosoma cruzi-infected rats, the reduction of acetylcholine content is due to gastric denervation and that the histamine increase might be secondary to gastric denervation and/or to an increase in the number of mast cells of the gastric wall

Presence of acethylcholine in the fruit of Physalis angulata (Solanaceae)

Acetilcolina foi encontrada no fruto da Physalus abgykata (Solanaceae), planta popularmente conhecida como camapu ou baläozinho, sua identificaçäo foi baseada nas seguintes observaçöes: a) contraçäo isotônica no reto anterior do sapo; b) efeito inotrópico e cronotrópico negativo no coraçäo isolado do sapo; c) contraçäo isotônica no jejuno do rato; d) hipertensäo arterial no gato. Essas açöes foram bloqueadas seletivamente pela galamina ou atropina e desapereceram pela incubaçäo do extrato com o plasma a 37-C. Além disso, a presença da acetilcolina no extrato foi confirmada pelo estudo cromatográfico. O valor médio de acetilcolcina foi de 123 µg/g de fruto

Presença da acetilcolina no fruto da Solanum melongena L / Presence of acetylcholine in fruits of Solanum melongena

Apresentam-se os resultados do estudo do efeito colinomimético dos extratos aquosos do fruto de Solanum melongena L., Solanaceae, vulgarmente conhecida no Brasil como berinjela roxa. A presença de acetilcolina nos extratos foi determinada através do teste de pressäo arterial do rato, de preparaçöes de musculatura lisa e estriada e ainda de ensaios de incubaçäo do extrato com plasma humano. Os efeitos observados foram seletivamente bloqueados por atropina ou galamina e potenciados com prostigmina

Effect of foot-electroshock stress on cholinergic activity, tissue glycogen and blood sugar in albino rats.

The immediate or 24 hr delayed effects of 1-day (1-DS) or (7-DS) foot-electroshock stress in albino rats were studied on cardiac acetylcholine (ACh), blood and cardiac cholinesterase (ChE) activities, cardiac, hepatic and muscle glycogen contents and blood sugar concentrations. The effects of physostigmine (PHY), atropine, 6-hydroxydopamine (6-HD), vagotomy and adrenalectomy on 1-DS induced changes were also studied. 1-DS produced an increase in cardiac ACh content which lasted for 24 hr but repeated stress showed phenomenon of adaptation. There seems to be activation of autonomic cholinergic system in stress. 1-DS and 7-DS produced a short-lived inhibition of blood ChE activity and 7-DS also of cardiac ChE activity. Inhibition of ChE activity was probably related to release of adrenaline from adrenal medulla. 1-DS produced hepatic and muscle glycogenolysis with slight hypoglycaemia but without any effect on cardiac glycogen. Following repeated stress there was a phenomenon of adaptation. The hepatic and muscle glycogenolysis produced by stress is due to the release of adrenaline from adrenal medulla. Normally functioning cardiac cholinergic system seems to have a protective effect on heart against stress, in the absence of which cardiac glycogenolysis is induced by stress.

Acetylcholine: a possible neurotransmitter in Setaria cervi.

The total and free acetylcholine (Ach) and cholinesterase (CHE) content of adult Setaria cervi were estimated. The Ach was estimated by bioassay on rectus abdominis muscle of frog and the CHE by measuring the drop in pH following incubation of worm homogenate with Ach chloride. The free and total Ach contents (4.0 +/- 0.57 and 6.0 +/- 0.48 microgram/g wet weight of worms respectively) were as high as found in mammalian brain cortex. The cholinesterase activity was found to be 5.57 +/- 0.6 units/g wet weight of worms. It is possible that there may exist a well developed system responsible for the synthesis, storage, release and destruction of Ach and that Ach may be acting as an excitatory neurohormone in S. cervi.

Effects of seasonal variations, acute hypothermia and physostigmine on cardiac acetylcholine, tissue glycogen and blood sugar concentrations in frogs.

The effects of seasonal variations and the effects of acute hypothermia (8.0 degrees) and/or physostigmine (PHY) in different seasons have been studied on the tissue glycogen, cardiac acetylcholine (ACh) and blood sugar contents in frogs. Seasonal variations had no significant effect on cardiac cholinergic activity. However, cardiac ACh concentration was significantly reduced by hypothermia in all seasons. The extents of increase in cardiac ACh in PHY pretreated hypothermic frogs indicate that hypothermia depresses cardiac cholinergic acitity much more in summers than in rainy and winter seasons. The tissue glycogen contents and blood sugar concentrations were significantly lower in winter season than those in summer and rainy seasons. Hypothermia produced marked tissue glycogenolysis and hyperglycaemia during summer and rainy seasons and not during winters. In general PHY had no effect on tissue glycogen contents in any season, but it produced hyperglycaemia during rainy and winter seasons. PHY pretreatment increased cardiac, hepatic and muscle glycogen contents and produced hyperglycaemia in hypothermic winter frogs, and it increased ventricular and muscle glycogen contents during summer and hepatic glycogen during rainy seasons, there being no significant effects on blood sugar.

Hypothermia and acetylcholine content of dog heart.

The acetylcholine level of dog heart has been determined under hypothermia. It was increased at 28 degrees C, and decrease at 20 degrees C. Further, it was observed that the heart rate and blood pressure decreased with gradual reduction in the body temperature of the dog and ventricular fibrillation occurred in 50% of the animals at 20 degrees C. It is proposed that cholinergic agents may have a role as antifibrillatory agents in hypothermia.