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Las respuestas hipofisarias a la administración continua e intermitente de la hormona liberadora de gonadotropina del
Science (New York, N.Y.)
|November 10, 1978
Resumen
La administración intermitente de la hormona liberadora de gonadotropina (GnRH) restaura la función pituitaria en monos, a diferencia de la infusión continua. Esto pone de relieve la importancia de la administración de GnRH pulsátil para la liberación sostenida de hormonas y evitar la desensibilización.
Área de la Ciencia:
- Endocrinología Reproductiva y Reproducción.
- La neuroendocrinología en neuroendocrinología.
- Fisiología de los primates.
Sus antecedentes:
- Las lesiones hipotalámicas eliminan la secreción de gonadotropinas pituitarias.
- La infusión constante de la hormona liberadora de gonadotropina (GnRH) no logra restaurar la secreción.
Objetivo del estudio:
- Para investigar el efecto de la administración intermitente versus continua de GnRH en la secreción de gonadotropinas en monos rhesus con lesiones hipotalámicas.
- Para determinar si el patrón de liberación de GnRH influye en la capacidad de respuesta de la hipófisis.
Principales métodos:
- Inducción de lesiones hipotalámicas en monos rhesus para abolir la GnRH. endógena.
- Administración de GnRH exógeno a través de infusión continua o pulsos intermitentes (horales).
- Monitoreo de la secreción de gonadotropina pituitaria en respuesta a diferentes patrones de administración de GnRH.
Principales resultados:
- La administración intermitente de GnRH (una vez por hora) restableció la secreción sostenida de gonadotropina pituitaria.
- La infusión continua de GnRH no pudo restaurar la secreción de gonadotropinas.
- La posterior administración continua de GnRH después de la restauración intermitente condujo a la desensibilización / desregulación.
Conclusiones:
- La administración pulsante de GnRH, que imita la frecuencia fisiológica, es crucial para restaurar y mantener la secreción de gonadotropinas pituitarias.
- El patrón de administración de GnRH, no solo la cantidad, dicta la capacidad de respuesta de la hipófisis.
- La GnRH continua puede conducir a la desensibilización de la glándula pituitaria.
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