Turner J T, Park M, Camden J M, Weisman G A
Department of Pharmacology and Biochemistry, University of Missouri School of Medicine, Columbia 65212, USA.
Ann N Y Acad Sci. 1998 Apr 15;842:70-5. doi: 10.1111/j.1749-6632.1998.tb09633.x.
Experiments were performed to document the presence of G protein-coupled P2Y nucleotide receptors in rat salivary glands and to examine changes in receptor expression during development and under conditions in which gland architecture is altered. The results indicate that, as opposed to mature rat submandibular gland (SMG), immature glands express functional P2Y1 receptors. P2Y1 receptor activity was highest at birth and declined over the next four weeks to undetectable levels. P2Y1 receptor mRNA levels remained constant over this time course, suggesting that receptor activity is regulated at some point other than transcription. Conversely, short-term culture of cells from the three major salivary glands resulted in upregulation of functional P2Y2 receptors. Responses to the P2Y2-selective agonist, UTP, were obtained after 3 h in culture and were maximal by 72 hours. This increase was paralleled by increased steady-state P2Y2 receptor mRNA levels. Upregulation of P2Y2 receptors also occurred in vivo following ligation of the main excretory duct of the SMG. These studies suggest that nucleotide receptors are dynamically regulated during development and as a result of perturbations to gland architecture.
进行实验以证明大鼠唾液腺中存在G蛋白偶联的P2Y核苷酸受体，并研究发育过程中以及腺体结构改变条件下受体表达的变化。结果表明，与成熟大鼠下颌下腺（SMG）不同，未成熟腺体表达功能性P2Y1受体。P2Y1受体活性在出生时最高，并在接下来的四周内下降至无法检测的水平。在此时间过程中，P2Y1受体mRNA水平保持恒定，表明受体活性在转录以外的某个点受到调节。相反，来自三大唾液腺的细胞短期培养导致功能性P2Y2受体上调。培养3小时后获得了对P2Y2选择性激动剂UTP的反应，并在72小时时达到最大值。这种增加与稳态P2Y2受体mRNA水平的增加平行。在SMG主排泄管结扎后，体内也发生了P2Y2受体的上调。这些研究表明，核苷酸受体在发育过程中以及由于腺体结构的扰动而受到动态调节。
