GENETIC POLYMORPHISMS HUMAN NOREPINEPHRINE TRANSPORTER

去甲肾上腺素转运蛋白（NET）负责通过快速重摄取释放的NE来限制去甲肾上腺素（NE）在脑和交感神经系统中的作用。该提案试图确定可能导致心血管和精神疾病的人类NET（hNET）基因突变。将对直立不耐受和抑郁患者的DNA样本进行hNET突变基因分型。将从血液或组织样本中分离基因组DNA，并使用针对hNET的引物进行聚合酶链反应和序列分析，以确定hNET编码区是否存在多态性。将通过含有hNET序列的表达载体的定点诱变、转染和[3H]NE转运试验的性能以及通过Western和放射性配体结合试验的蛋白质分析，检查导致氨基酸取代的突变对hNET的影响。还将检查在高血压中鉴定的已知多态性对hNET功能的影响。通过鉴定影响去甲肾上腺素能功能的疾病中的hNET突变，将实现对去甲肾上腺素能神经传递机制的进一步理解，并且可以开发针对这些疾病的选择性靶向hNET的成功疗法。

The norepinephrine transporter (NET) is responsible for limiting the actions of norepinephrine (NE) in the brain and in the sympathetic nervous system through rapid reuptake of released NE. This proposal attempts to identify mutations in the human NET (hNET) gene that may contribute to cardiovascular and psychiatric disease. DNA samples from patients with orthostatic intolerance and depression will be genotyped for hNET mutations. Genomic DNA will be isolated from blood or tissue samples, and, using primers directed against hNET, polymerase chain reaction and sequence analysis will be performed to determine if polymorphisms exist in coding region of hNET. Mutations that result in amino acid substitutions will be examined for effects on hNET through site-directed mutagenesis of an expression vector containing hNET sequences, transfection and performance of [3H]NE transport assays and protein analysis through Western and radioligand binding assays. Known polymorphisms identified in hypertension will also be examined for their effects on hNET function. Through identification of hNET mutations in diseases affecting noradrenergic function, further understanding of the mechanism of noradrenergic neurotransmission will be achieved and successful therapies for these disorders can be developed that selectively target hNET.