Zhang X, Shi T, Holmberg K, Landry M, Huang W, Xiao H, Ju G, Hökfelt T
Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
Proc Natl Acad Sci U S A. 1997 Jan 21;94(2):729-34. doi: 10.1073/pnas.94.2.729.
The Y2 subtype of neuropeptide tyrosine (NPY) receptors (Y2R) and some neuropeptides have been studied with in situ hybridization in sensory and autonomic neurons of rat and monkey. Between 10% and 20% of the lumbar dorsal root ganglion (DRG) neuron profiles (NPs) contain Y2R mRNA in the rat and monkey. In rat DRGs Y2R mRNA is expressed in calcitonin gene-related peptide (CGRP)-positive, medium-sized, and large neurons, that is in a complementary fashion to the Y1R that is located in small CGRP neurons. In monkey DRGs Y2R mRNA is expressed mainly in small neurons. Peripheral axotomy up-regulates the Y2R in small and large DRG neurons in both species. Y2R and NPY mRNAs are colocalized in many large neurons in axotomized rat DRGs. Y2R mRNA is expressed in 50% of the NPs in the nodose ganglion with a modest increase after axotomy. Y2R mRNA is detected in a few NPs in normal rat superior cervical ganglia, with a marked increase after transection of the carotid nerves. No Y2R mRNA-positive, but many (approximately 30%) weakly Y1R mRNA-positive NPs were found in the sphenopalatine ganglion. Finally, Y2R mRNA levels increase in rat spinal motoneurons after axotomy. Thus, under normal circumstances NPY may act on Y1 and Y2Rs expressed, respectively, in small and large CGRP-positive DRG neurons in the rat. Y2R may be an important receptor in the viscero-sensory neurons. Y2Rs may be particularly important after axotomy serving as presynaptic and/or autoreceptors on rat DRG, superior cervical ganglion, and nodose ganglion neurons and as presynaptic receptors in monkey DRG neurons.
已运用原位杂交技术在大鼠和猴的感觉神经元及自主神经元中对神经肽Y（NPY）受体的Y2亚型（Y2R）和一些神经肽进行了研究。在大鼠和猴中，10%至20%的腰段背根神经节（DRG）神经元轮廓（NP）含有Y2R mRNA。在大鼠DRG中，Y2R mRNA在降钙素基因相关肽（CGRP）阳性的中型和大型神经元中表达，这与位于小型CGRP神经元中的Y1R呈互补表达模式。在猴DRG中，Y2R mRNA主要在小型神经元中表达。两种动物的外周轴突切断术均上调了小型和大型DRG神经元中的Y2R。Y2R和NPY mRNA在轴突切断的大鼠DRG中的许多大型神经元中共定位。Y2R mRNA在结状神经节中50%的NP中表达，轴突切断后略有增加。在正常大鼠颈上神经节的少数NP中检测到Y2R mRNA，在切断颈神经后显著增加。在蝶腭神经节中未发现Y2R mRNA阳性的NP，但有许多（约30%）Y1R mRNA弱阳性的NP。最后，轴突切断后大鼠脊髓运动神经元中的Y2R mRNA水平升高。因此，在正常情况下，NPY可能分别作用于大鼠中表达于小型和大型CGRP阳性DRG神经元的Y1R和Y2R。Y2R可能是内脏感觉神经元中的重要受体。Y2R在轴突切断后可能特别重要，可作为大鼠DRG、颈上神经节和结状神经节神经元上的突触前和/或自身受体，以及猴DRG神经元上的突触前受体。
