Ye Ping, Kenyon Christopher J, MacKenzie Scott M, Seckl Jonathan R, Fraser Robert, Connell John M C, Davies Eleanor
Medical Research Council Blood Pressure Group, Western Infirmary, Glasgow, Scotland G11 6NT, United Kingdom.
Endocrinology. 2003 Aug;144(8):3321-8. doi: 10.1210/en.2003-0109.
We have developed a highly sensitive QRT-PCR method for the measurement of CYP11B1 (11beta-hydroxylase) and CYP11B2 (aldosterone synthase) mRNAs to study their expression in the rat brain in response to dietary sodium manipulation and angiotensin (Ang)II infusion. Male Wistar Kyoto rats (n = 6) were fed normal, high, or low sodium diets for 12 d or were administered AngII or vehicle for 7 d. CYP11B2 and CYP11B1 expression was measured in RNA from adrenal gland and discrete brain regions using real-time QRT-PCR. Sodium restriction increased adrenal CYP11B2 expression 57-fold from 1.0 x 10(5) +/- 0.6 x 10(5) to 57 x 10(5) +/- 22 x 10(5) copies/ microg RNA (mean +/- SEM; P < 0.05);in the hippocampus, 14-fold from 5.4 x 10(2) +/- 0.8 x 10(2) to 74 x 10(2) +/- 31 x 10(2) copies/ microg RNA (P < 0.05); and in the cerebellum, 5-fold from 1.9 x 10(3) +/- 0.7 x 10(3) to 9.9 x 10(3) +/- 3.0 x 10(3) copies/ microg RNA (P < 0.01). CYP11B2 gene expression in the brainstem and hypothalamus was not affected. High-sodium diet reduced adrenal CYP11B2 expression to 0.19 x 10(5) +/- 0.1 x 10(5) copies/ microg RNA (P < 0.05) but did not affect central nervous system (CNS) expression significantly. AngII significantly increased adrenal CYP11B2 expression but did not affect CNS expression. Brain CYP11B1 mRNA levels were 10- to 1000-fold higher than CYP11B2 but were unaffected by dietary sodium or AngII. To summarize, we have identified a local CYP11B2 response to sodium depletion in the hippocampus and cerebellum. This is the first such regulation of CYP11B2 transcription to be identified in the CNS.
我们开发了一种高灵敏度的定量逆转录聚合酶链反应（QRT-PCR）方法，用于检测CYP11B1（11β-羟化酶）和CYP11B2（醛固酮合酶）的信使核糖核酸（mRNA），以研究它们在大鼠脑中对饮食钠调控和血管紧张素（Ang）II输注的反应。雄性Wistar Kyoto大鼠（n = 6）分别给予正常、高或低钠饮食12天，或给予AngII或赋形剂7天。使用实时QRT-PCR检测肾上腺和离散脑区RNA中的CYP11B2和CYP11B1表达。钠限制使肾上腺CYP11B2表达从1.0×10^5±0.6×10^5增加到57×10^5±22×10^5拷贝/微克RNA，增加了57倍（平均值±标准误；P < 0.05）；在海马体中，从5.4×10^2±0.8×10^2增加到74×10^2±31×10^2拷贝/微克RNA，增加了14倍（P < 0.05）；在小脑中，从1.9×10^3±0.7×10^3增加到9.9×10^3±3.0×10^3拷贝/微克RNA，增加了5倍（P < 0.01）。脑干和下丘脑的CYP11B2基因表达未受影响。高钠饮食使肾上腺CYP11B2表达降低至0.19×10^5±0.1×10^5拷贝/微克RNA（P < 0.05），但对中枢神经系统（CNS）表达无显著影响。AngII显著增加肾上腺CYP11B2表达，但不影响CNS表达。脑CYP11B1 mRNA水平比CYP11B2高10至1000倍，但不受饮食钠或AngII影响。总之，我们在海马体和小脑中发现了CYP11B2对钠缺乏的局部反应。这是首次在中枢神经系统中发现CYP11B2转录的这种调控。
