Study on the Application of Liquid Chromatography-Tandem Mass Spectrometry for the Determination of Aldosterone and Renin Activity in the Diagnosis of Primary Aldosteronism by Captopril Test

Normal Control Group Inclusion Criteria * Age 18-70 years old * BMI: 18.5-23.9kg/m² * Gender not restricted * Blood pressure: 100-120/60-80mmHg * No history of hypertension * No abnormal nodules found in adrenal CT * Previous blood potassium and electrocardiogram were all within normal ranges * No history of liver or kidney dysfunction, malignant tumors, metabolic diseases or cardiovascular diseases * No medication used Exclusion Criteria * Those with a family history of hypertension or with clinical manifestations of secondary hypertension * Those who have been taking drugs that may affect the RAAS system for a long time (such as contraceptives, steroids, etc.) * Those with cardiac dysfunction or severe arrhythmia and unable to tolerate the test Patients with suspected primary aldosteronism Inclusion Criteria: * Patients with suspected primary aldosteronism in the outpatient setting * Willing to undergo 4-week spironolactone treatment and cooperate with follow-up Exclusion Criteria: * Patients who did not complete the captopril suppression test * Patients with Cushing's syndrome or other endocrine tumors * Patients allergic to spironolactone or with contraindications for its use (such as severe hyperkalemia, eGFR \< 30) * History of liver or kidney dysfunction * Coexisting severe cardiovascular or cerebrovascular diseases * History of malignant tumors * Other types of endocrine hypertension (hyperthyroidism, pheochromocytoma, Cushing's syndrome, etc.) * Renal artery stenosis * Hypokalemia caused by other factors (renal tubular acidosis, Bartter syndrome, Gitelman syndrome, etc.) * Diabetes with HbA1c \> 7.0% or currently using or having used insulin or SGLT2 inhibitor drugs * Taking special medications such as glucocorticoids, immunosuppressants, oral contraceptives, etc