Department of Urology, Nara Medical University, Kashihara, Japan.
Department of Urology, Nara Medical University, Kashihara, Japan.
Life Sci. 2022 Oct 1;306:120842. doi: 10.1016/j.lfs.2022.120842. Epub 2022 Jul 29.
To examine the circadian expression changes in bladder clock genes in Dahl salt-sensitive rats following high salt intake.
Eighteen rats were divided into three groups: the high-salt diet group (HS group), the normal-salt diet group (NS group), and the salt-load interruption group (from a 4 % salt diet to a normal diet; salt-load interruption group [SI group]). Each rat was placed in an individual metabolic cage for 24 h twice weekly. Water intake, urine production, voiding frequency, and voided volume per micturition were recorded. Furthermore, 108 control rats were prepared. Bladders were harvested every 4 h at six time points. Furthermore, the mRNA expression of clock genes and mechanosensors was analyzed.
In the HS group, the bladder clock genes showed lower mRNA levels than in the NS group. The amplitude of circadian expression changes in bladder clock genes in the HS group was lower than that in the NS group. However, after changing from a 4 % salt diet to a normal diet, the waveforms of the clock gene expression in the SI group were closer to those of the NS group. The 24-h water intake and urinary volume of the SI group decreased to levels comparable to those of the NS group.
Reduced salt intake partially restored the circadian rhythms of bladder clock genes.
观察高盐饮食后 Dahl 盐敏感大鼠膀胱时钟基因的昼夜表达变化。
将 18 只大鼠分为三组：高盐饮食组（HS 组）、正常盐饮食组（NS 组）和盐负荷中断组（从 4%盐饮食改为正常饮食；盐负荷中断组[SI 组]）。每周两次，将每只大鼠置于单独的代谢笼中 24 小时。记录水摄入量、尿量、排尿频率和每次排尿量。此外，还准备了 108 只对照大鼠。每隔 4 小时在六个时间点采集膀胱。此外，还分析了时钟基因和机械感受器的 mRNA 表达。
在 HS 组中，膀胱时钟基因的 mRNA 水平低于 NS 组。HS 组膀胱时钟基因昼夜表达变化的振幅低于 NS 组。然而，从 4%盐饮食改为正常饮食后，SI 组时钟基因表达的波形更接近 NS 组。SI 组的 24 小时水摄入量和尿量减少到与 NS 组相当的水平。
减少盐的摄入部分恢复了膀胱时钟基因的昼夜节律。
