A STUDY ON THE MECHANISM UNDERLYING MILK EJECTION BURSTS OF OXYTOCIN CELLS.

催产素细胞喷乳爆发机制的研究。

• 批准号: 07680869
• 负责人: NEGORO Hideo
• 金额: $ 1.22万
• 依托单位: Fukui Medical School
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07680869/
• 关键词: oxytocin; milk ejectin reflex; burst discharge; synchronization; afferent pathway; summatin mechanism; gate

In order to study the neural mechanisms to generate burst activities of oxytocin neurones during suckling in lactating rats, the following three studies were made :(1) the effect of midbrain-hemitransection on amplitudes and time courses of milk ejection bursts of oxytocin neurones in lactating rats.Extracellular recordings of the electrical activity of oxytocin neurones were made from the supraoptic nuclei of lactating rats, and the milk-ejection bursts were investigated in the midbrain-hemitransected rats. Of the burst recorded from oxytocin neurones on the lesioned side, the amplitude was smaller, the onset time was later and the burst span was shorter than those recorded on the non-lesion-ed side. These results indicated that the amplitude and time course of the burst of oxytocin neurones mainly depend on suckling information from the nipples on their opposite side.(2) the effects of unilateral suckling on milk ejection bursts of oxytocin neurones in intact rats.When application of pups was limited to the nipples on either the same side or the side opposite to the oxytocine neurone recorded, the burst amplitude was significantly lower than during bilateral suckling. Furthermore, the burst amplitude was significantly lower during ipsilateral suckling than during contralateral suckling. The finding indicates that the burst amplitude mainly depends on the amount of afferent suckling signals arising from the nipplies on the side opposite to the reocording side.(3) the effect of interhemispheric sections of the hypothalamus on milk-ejection bursts of supraoptic oxytocin neurones.Extensive interhemispheric sectioning did not abolish the burst of oxytocin neurones during bilateral and contralateral suckling but reduced the number of oxytocine neurones that showed the burst during ipsilateral suckling. The result suggest that there are two separate gate and summation mechanisms on each side of the hypothalamus.

为了研究哺乳期大鼠哺乳期间催产素神经元产生爆发活动的神经机制，进行了以下三项研究：(1)中脑半横断对哺乳期大鼠催产素神经元喷乳爆发幅度和时间过程的影响。 研究人员对哺乳大鼠的细胞核和中脑半横断大鼠的乳汁喷射进行了研究。病变侧催产素神经元记录的爆发比非病变侧记录的振幅更小，发作时间更晚，爆发跨度更短。这些结果表明，催产素神经元爆发的幅度和时程主要取决于对侧乳头的哺乳信息。（2）单侧哺乳对完整大鼠催产素神经元喷奶爆发的影响。当幼仔仅限于记录的催产素神经元同侧或对侧乳头时，爆发幅度显着降低。 与双侧哺乳时相比。此外，同侧哺乳期间的爆发幅度显着低于对侧哺乳期间。研究结果表明，爆发幅度主要取决于记录侧乳头传入的吸吮信号的数量。（3）下丘脑半球间切片对视上催产素神经元乳汁喷射爆发的影响。 双侧和对侧哺乳，但减少了在同侧哺乳期间表现出爆发的催产素神经元的数量。结果表明，下丘脑的每一侧都有两个独立的门和求和机制。

项目成果

Wang,Y-F.,Negoro,H.,Honda,K.: "Effects of hemitransection of the medbrain on milk-ejection burst of oxytocin neurones in lactating rat." Journal of Endocrinology. 144. 463-470 (1995)

Wang，Y-F.，Negoro，H.，Honda，K.：“中脑半横切对哺乳大鼠催产素神经元乳汁喷射爆发的影响”。

Wang, Y-F., Negoro, H., Honda, K.: "Effects of hemitransection of the medbrain on milk-ejection burst of oxytocin neurones in lactating rat." J. Endocrinology. 144. 463-470 (1995)

Wang, Y-F.、Negoro, H.、Honda, K.：“中脑半横断对哺乳大鼠催产素神经元喷乳爆发的影响”。