Priest C A, Vink K L, Micevych P E
Department of Anatomy and Cell Biology, UCLA School of Medicine 90024-1763.
Brain Res Mol Brain Res. 1995 Jan;28(1):61-71. doi: 10.1016/0169-328x(94)00184-g.
In the rat, reproduction and sexual behavior are controlled by the gonadal steroid regulation of synaptic interactions within the sexually dimorphic limbic-hypothalamic system. The effects of estrogen on the ventromedial nucleus of the hypothalamus, one nucleus within the circuit, are central to the modulation of this behavior. Involvement of the neuropeptide substance P, a member of the tachykinin family of neuropeptides, has been implicated in the regulation of both lordosis behavior and gonadotropin release. However, previous studies have provided conflicting evidence as to whether levels of substance P in the ventromedial nucleus of the hypothalamus are modulated by circulating estrogens. To study this question further, in situ hybridization histochemistry was used to examine levels of beta-preprotachykinin mRNA, which encodes substance P and other tachykinins, in the ventrolateral subdivision of the ventromedial hypothalamus at 10 consecutive timepoints over a 4 day period subsequent to an acute administration of estrogen. Following estrogen treatment, beta-preprotachykinin mRNA expression was increased in cells of the ventrolateral portion of the ventromedial nucleus of the hypothalamus which constitutively express beta-preprotachykinin mRNA; however, there were no statistically significant changes in the number of cells that express detectable levels of beta-preprotachykinin mRNA in the ventrolateral portion of the ventromedial nucleus. Estrogen treatment produced two peaks of beta-preprotachykinin mRNA expression, the first at 2 h and the second at 48 h after the injection of estrogen. These data indicate that estrogen has both rapid and prolonged effects on beta-preprotachykinin mRNA levels, suggesting that estrogen may affect different cellular mechanisms relevant to the induction of beta-preprotachykinin mRNA expression.
在大鼠中，生殖和性行为受性腺甾体对性二态性边缘 - 下丘脑系统内突触相互作用的调节。雌激素对下丘脑腹内侧核（该回路中的一个核）的作用是这种行为调节的核心。神经肽P物质（速激肽家族神经肽的一员）参与了脊柱前凸行为和促性腺激素释放的调节。然而，先前的研究对于下丘脑腹内侧核中P物质的水平是否受循环雌激素调节提供了相互矛盾的证据。为了进一步研究这个问题，在急性给予雌激素后的4天内，连续10个时间点使用原位杂交组织化学来检测下丘脑腹内侧外侧亚区中编码P物质和其他速激肽的β-前速激肽原mRNA水平。雌激素处理后，下丘脑腹内侧核腹侧部分中组成性表达β-前速激肽原mRNA的细胞中β-前速激肽原mRNA表达增加；然而，下丘脑腹内侧核腹侧部分中表达可检测水平β-前速激肽原mRNA的细胞数量没有统计学上的显著变化。雌激素处理产生了β-前速激肽原mRNA表达的两个峰值，第一个在注射雌激素后2小时，第二个在48小时。这些数据表明雌激素对β-前速激肽原mRNA水平具有快速和持久的影响，提示雌激素可能影响与β-前速激肽原mRNA表达诱导相关的不同细胞机制。
