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La apamina bloquea ciertos aumentos inducidos por los neurotransmisores en la permeabilidad del potasio
Nature
|November 22, 1979
Resumen
La apamina, una neurotoxina del veneno de abeja, bloquea la actividad de los canales de potasio inducida por ATP en el músculo liso. Este hallazgo sugiere que la apamina no es un bloqueador específico del receptor de ATP, sino que inhibe los cambios en la permeabilidad del potasio.
Área de la Ciencia:
- Neurofarmacología y Neurofarmacología.
- Fisiología del músculo liso Fisiología del músculo liso
- Investigación sobre el veneno de abeja.
Sus antecedentes:
- La apamina, un polipéptido neurotóxico del veneno de abeja, tiene una estructura conocida.
- Estudios anteriores sugirieron que el ATP es un neurotransmisor en el suministro nervioso inhibidor no adrenérgico al músculo liso visceral.
- La apamina fue identificada tentativamente como un bloqueador postsináptico específico de esta inhibición purinérgica.
Objetivo del estudio:
- Para investigar el mecanismo de acción de la apamina en el músculo liso visceral.
- Para determinar si la apamina actúa como un bloqueador postsináptico específico para la inhibición mediada por ATP.
- Para aclarar el papel de la apamina en la inhibición no adrenérgica y purinérgica.
Principales métodos:
- Confirmación experimental del efecto de la apamina sobre el ATP y la inhibición inducida por la estimulación nerviosa.
- Investigación del impacto de la apamina en la permeabilidad del potasio.
- Utilizó concentraciones nanomolares de apamina en preparaciones de músculo liso visceral (estómago de conejillo de indias y taenia coli).
Principales resultados:
- La apamina en concentraciones nanomolares reduce la inhibición tanto por el ATP aplicado externamente como por la estimulación nerviosa no adrenérgica.
- Se encontró que la apamina inhibe el aumento de la permeabilidad del potasio inducida por el ATP.
- Los resultados sugieren que la acción de la apamina no es específica de los receptores ATP.
Conclusiones:
- La apamina inhibe el aumento de la permeabilidad del potasio causado por el ATP y otros agentes.
- La apamina no es un bloqueador postsináptico específico de los receptores ATP.
- El efecto más amplio de la apamina sobre la permeabilidad del potasio subyace en su acción inhibidora sobre la inhibición no adrenérgica, purinérgica del músculo liso.
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