Fig. 1

Flowchart of the whole study including the model groups and control groups. A total of 156 rats, including 78 SHRs and 78 WKYs, were divided into 13 groups. After 8 weeks, the rats were sacrificed every 2 h, and serum was collected. UPLC-Q-exactive-MS was used to collect serum data, and Compound Discoverer was used to analyse metabolites. The metabolites showing a circadian rhythm and associated with hypertension were regarded as differential biomarkers. Enrichment analysis of the biomarkers found that amino acid metabolism is an important rhythm-related metabolic process. Based on this result, amino acids were quantitatively analysed to determine the trend of each amino acid over 24 h