THE ROLE OF PATTERNED BURST AND INTERBURST INTERVAL ON THE EXCITATION-COUPLING MECHANISM IN THE ISOLATED RAT NEURAL LOBE
THE ROLE OF PATTERNED BURST AND INTERBURST INTERVAL ON THE EXCITATION-COUPLING MECHANISM IN THE ISOLATED RAT NEURAL LOBE
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DOI：
10.1113/jphysiol.1985.sp015887
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发表时间：
1985-01-01
影响因子：
5.5
通讯作者：
NORDMANN, JJ
中科院分区：
文献类型：
--
作者：
CAZALIS, M;DAYANITHI, G;NORDMANN, JJ
1.电刺激离体大鼠神经叶，用放射免疫法测定加压素和催产素的释放。用恒定频率的脉冲或模仿体内记录的加压素或催产素的大细胞神经元的电活动的脉冲模式刺激神经垂体。2.从“加压素”细胞记录的单个爆发，爆发内平均频率为13 Hz，比以13 Hz的恒定频率提供的相同数量的刺激诱发更多的加压素释放。3.每脉冲的加压素释放量在开始时比在爆发结束时高得多。4.一系列的爆发与爆发间的沉默期释放更多的激素比没有沉默期的爆发。5.四个“加压素”爆发释放的激素量在21秒的沉默期比在更短的时间间隔显着更大。6.四个脉冲were更有效地促进激素释放时，给予60毫秒的峰间期在每秒钟的开始时，比在一个恒定的频率为4赫兹。7.长时间的“加压素”脉冲串刺激在诱导激素释放方面比以13 Hz的恒定频率提供的脉冲串中给予相同数量的脉冲具有更大的效果。在最初的增加后，加压素的释放速率迅速下降，而催产素的释放在前20分钟保持升高，然后才下降。然而，加压素和催产素的释放仍然高于未受刺激的神经垂体的释放。8. 45 Ca摄取在神经叶是更大的神经垂体时，加压素或催产素脉冲串提供沉默的时间间隔刺激时，沉默期被省略，或当组织被刺激脉冲串相同数量，但在恒定的频率为13 Hz。9.总之，它表明，在一个突发和突发之间的沉默间隔的棘波间期是两个重要的决定因素的有效性的突发模式，在促进神经肽的释放。
1. Isolated rat neural lobes were stimulated electrically and the release of vasopressin and oxytocin was measured by radioimmunoasssay. The neurohypophyses were stimulated with pulses given at a constant frequency or with a pulse pattern imitating the electrical activity, recorded in vivo, of vasopressin- or oxytocin-containing magnocellular neurones. 2. A single burst recorded from a ''vasopressin'' cell with an intraburst mean frequency of 13 Hz evoked more vasopressin release than the same number of stimuli delivered at a constant frequency of 13 Hz. 3. The amount of vasopressin release per pulse was much higher at the beginning than at the end of the burst. 4. Series of bursts given with interburst silent periods released more hormone than bursts delivered without silent periods. 5. The amount of hormone released by four ''vasopressin'' bursts was significantly larger with silent periods of 21 s than with shorter intervals. 6. Four pulses wre much more effective in promoting hormone release when given with 60 ms interspike intervals at the beginning of each second than when delivered at a constant frequency of 4 Hz. 7. Prolonged stimulation with ''vasopressin'' bursts had a greater effect in inducing hormone release than the same number of pulses given in bursts delivered at a constant frequency of 13 Hz. After an initial increase the rate of vasopressin release delcined rapidly whereas oxytocin release remained elevated for the first 20 min and only then decreased. The release of both vasopressin and oxytocin remained, however, above the release from unstimulated neurohypophyses. 8. 45Ca uptake in the neural lobe was larger when the neurohypophyses were stimulated with vasopressin or oxytocin bursts delivered with silent intervals than when the silent periods were omitted, or when the tissue was stimulated with bursts with the same number of pulses but given at a constant frequency of 13 Hz. 9. In conclusion, it is suggested that the interspike intervals in a burst and the silent intervals between bursts are two important determinants of the effectiveness of the burst pattern in promoting neuropeptide release.