[Changes in amino acid profiling in spontaneously hypertensive rats and regulatory effect of extract from Coreopsis tinctoria].

To compare the amino acid metabolic profiling in urine of spontaneously hypertensive rats (SHR) and normal Wistar rats, and investigate the regulatory effect of extract from Coreopsis tinctoria on blood pressure and amino acid metabolic profiling in SHR. Right aged SHR and Wistar rats were housed to fit the new environment for 2 weeks. After that, their systolic pressure(SBP), diastolic pressure(DBP) were measured and urine was collected. Amino acids profiles for SHR and Wistar rats were acquired by using AQC precolumn derivatization HPLC-fluorescence method, and then partial least squares discriminant analysis(PLS-DA) was applied to facilitate differentiation and determine metabolic differences between collected samples from two groups of rats. Consequently, 40 SHR were randomly divided into 5 groups: model group, high, middle, low dosage groups of C. tinctoria extract (3.2, 1.6,0.8 g•kg⁻¹), and captopril group (4 mg•kg⁻¹). They were treated for 4 weeks by ig administration, and then their urine samples were collected to determine the amino acid metabolic profiling in various groups. After treatment for 4 weeks, as compared with Wistar group, serine, alanine, tyrosine, and cystine in the amino acid metabolic profiling were significantly increased in SHR group. As compared with SHR model group, threonine and methionine were decreased significantly in captopril group (P<0.01); amino acid metabolism was changed to different degrees in high, middle, and low dosage groups of C. tinctoria extract, and the threonine in low dose group was significantly decreased (P<0.01); serine and threonine were decreased (P<0.05), and valine, methionine and lysine were significantly decreased (P<0.01) in middle dose group; threonine, valine, methionine and lysine were significantly decreased in large dose group (P<0.01). The results showed that middle and high doses of extract from C. tinctoria could significantly improve disturbance of amino acid metabolism, help to further clarify the drug property research of C. tinctoria, and provide data support for amino acid metabolic pathway abnormalities in hypertension patients.