Coexistence of neuroactive substances in single neurons

1)单个运动神经元中神经活性物质的共存我们已经证明，乙酰胆碱(Ach)和降钙素基因相关肽在单个运动神经元中共存。我们用药理学方法确定，用一种膈神经隔膜制剂，在刺激神经纤维或直接刺激肌肉时，这种多肽能增强肌肉收缩。这种作用可能是通过这种多肽的受体而不是Ach受体实现的。此外，我们还发现CGRP还以剂量依赖的方式引起横纹肌中cAMP的增加。II)单个感觉神经元中神经活性物质的共存我们证明了CGRP在感觉神经节中也与P物质(SP)共存。伤害性刺激可使感觉神经元中编码P物质的PtTa基因表达增强，提示P物质与伤害性感觉…的关系更为密切更多的n传导系统。另一方面，在背角，SP和脑啡肽(Enk)在单个神经元中共存。前脑啡肽原(PPE)mRNA在伤害性刺激后1小时内表达增加，表明在脊髓背角水平，EnK与伤害性传导系统的关系比SP更密切。III)存在含有三种以上神经活性物质的神经元臂旁外侧区含有大量CGRP、SP和神经降压素(NT)神经元。损毁臂旁外侧区外亚核，杏仁中央核(AC)内CGRP、SP和NT纤维消失。此外，这些肽能神经元在外亚核的分布模式非常相似，表明三种肽在这里的单个神经元中定位。事实上，免疫细胞化学双重染色分析显示，这里的大多数SP神经元含有NT。交替连续切片的免疫组织化学分析显示，这些神经元中的许多也含有CGRP。为了研究单个神经元中三种以上神经活性物质共存的意义，需要阐明神经受体的定位。我们现在正在努力解决这个问题。较少

I) Coexistence of neuroactive substances in single motor neurons We have previously shown the findings that acetylcholine (Ach) and calcitinin gene-related peptide coexist in single motor neurons. We determined, using pharmacological means, with a phrenic nerve diaphragm preparation, that this peptide enhances muscle contraction during stimulation of the nerve fibers or direct stimulation of the muscle. This effect is probably brought about via the receptor for this peptide not the Ach receptors. Furthermore, we have shown that CGRP also caused an increase in cyclic AMP in the striated muscle with a dose dependent manner.II) Coexistence of neuroactive substances in single sensory neurons We have demonstrated that CGRP also coexists with substance P (SP) in single small sized neurons in the sensory ganglia. Nociceptive stimulation resuled in a enhancement of preprotachychinine A (PTTA) mRNA which codes SP in sensory neurons, indicating that SP related much more closely to the nociceptio … More n conduction system. On the other hand, in the dorsal horn, SP coexists with enkephalin (Enk) in single neurons. Expression of preproenkephalin (PPE) mRNA increased within 1 hour after nociceptive stimulation, demonstrating that at the level of the dorsal horn of the spinal cord, Enk is related more closely to the nociception conducting system than SP.III) Presence of neurons containing more than three neuroactive substances Lateral parabrachial area contains a number of CGRP-, SP-and neurotensin (NT)-containing neurons. Destruction of the external subnucleus of the lateral perabrachial area resuled in a disappearance of CGRP, SP and NT fiders in the central amygdaloid nucleus (AC). In addition, distribution pattern of these peptidergic neurons in the external subnucleus is very similar, suggesting that three kinds of peptides localize in single neurons here. In facts, immunocytochemical double staining analysis revealed that most of sp neurons here contained NT. Immunohistochemical analysis of alternative consecutive sections showed that many of these neurons also contained CGRP. In order to examine the significance of the coexistence of more than three neuroactive substances in single neurons, the localization neuroreceptors should be elucidated. We are now working on this problem. Less