Effect of prolactin replacement on the number of tyrosine hydroxylase expressing neurons in the arcuate nuclei of Ames dwarf and normal mice.
Effect of prolactin replacement on the number of tyrosine hydroxylase expressing neurons in the arcuate nuclei of Ames dwarf and normal mice.
复制标题
催乳素替代对艾姆斯侏儒和正常小鼠弓状核中表达酪氨酸羟化酶的神经元数量的影响。
DOI：
10.1159/000125541
复制
发表时间：
1990
影响因子：
4.1
通讯作者：
Besch,KC
中科院分区：
文献类型：
--
作者：
Morgan,WW;Besch,KC
艾姆斯矮鼠不能合成或释放生长激素或催乳素（PRL），并且发育不良的结节基底多巴胺能（ΗDA）神经元。本研究使用酪氨酸羟化酶抗体（酪氨酸羟化酶是多巴胺生物合成中的限制性酶）和免疫组织化学方法，比较了Ames侏儒小鼠弓形核中观察到的TH免疫阳性神经元的数量与同一品系的表型正常小鼠的数量。与正常雌性相比，雌性侏儒弓形核中th免疫阳性神经元的数量明显减少，而致密部中th免疫阳性神经元的数量没有明显减少。通过在肾包膜下植入正常垂体或每天给药羊PRL，循环PRL的升高增加了弓形神经元的数量，这些神经元表达免疫化学可检测到的TH，其水平与未治疗的正常小鼠相当。矮雄性弓形核中表达th的神经元数量也减少，但减少幅度没有雌性大。绵羊PRL似乎对侏儒或正常雄性小鼠中th免疫阳性神经元的数量几乎没有影响。这些结果表明，小鼠出生后PRL的缺失并不会导致ΗDA神经元总数的大幅减少。相反，这些神经元似乎以接近正常的数量存在，但在缺乏循环PRL的情况下处于休眠状态。
Ames dwarf mice do not synthesize or release growth hormone or prolactin (PRL) and have very poorly developed tuberoinfundibular dopaminergic (ΗDA) neurons. An antibody to tyrosine hydroxylase (TH), the rate-limiting enzyme in the biosynthesis of dopamine, and immunohistochemical procedures were used in this study to compare the numbers of TH-immuno-positive neurons observed in the arcuate nuclei of Ames dwarf mice compared to phenotypically normal mice of the same strain. In female dwarfs, the number of TH-immunopositive neurons in the arcuate nuclei but not the pars compacta was markedly reduced when compared to normal females. The elevation of circulating PRL either by the implantation of a normal pituitary under the kidney capsule or by the daily administration of ovine PRL increased the numbers of arcuate neurons which expressed immunochemically detectable TH to a level comparable to that observed in untreated normal mice. The number of TH-expressing neurons was also reduced in the arcuate nuclei of dwarf males although the deficiency was not as great as in females. Ovine PRL seemed to have little effect on the numbers of TH-immunopositive neurons observed in either dwarf or normal male mice. These results suggest that the postnatal absence of PRL in mice does not result in a major reduction in the total population of ΗDA neurons. Rather these neurons appear to be present in nearly normal numbers but are in a dormant state in the absence of circulating PRL.