Human Tissue Kallikrein Activity in Angiographically Documented Chronic Stable Coronary Artery Disease.
BACKGROUND
Human tissue kallikrein (hK1) is a key enzyme in the kallikrein-kinin system (KKS). hK1-specific amidase activity is reduced in urine samples from hypertensive and heart failure (HF) patients. The pathophysiologic role of hK1 in coronary artery disease (CAD) remains unclear.


OBJECTIVE
To evaluate hK1-specific amidase activity in the urine of CAD patientsMethods:Sixty-five individuals (18-75 years) who underwent cardiac catheterism (CATH) were included. Random midstream urine samples were collected immediately before CATH. Patients were classified in two groups according to the presence of coronary lesions: CAD (43 patients) and non-CAD (22 patients). hK1 amidase activity was estimated using the chromogenic substrate D-Val-Leu-Arg-Nan. Creatinine was determined using Jaffé's method. Urinary hK1-specific amidase activity was expressed as µM/(min · mg creatinine) to correct for differences in urine flow rates.


RESULTS
Urinary hK1-specific amidase activity levels were similar between CAD [0.146 µM/(min ·mg creatinine)] and non-CAD [0.189 µM/(min . mg creatinine)] patients (p = 0.803) and remained similar to values previously reported for hypertensive patients [0.210 µM/(min . mg creatinine)] and HF patients [0.104 µM/(min . mg creatinine)]. CAD severity and hypertension were not observed to significantly affect urinary hK1-specific amidase activity.


CONCLUSIONS
CAD patients had low levels of urinary hK1-specific amidase activity, suggesting that renal KKS activity may be reduced in patients with this disease.
Departamento de Cardiologia, Hospital Lifecenter, Belo Horizonte, MG, Brazil.
Estêvão Lanna
EL
Figueiredo
Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
Carolina Antunes
CA
Magalhães
Divisão de Cardiologia, Laboratório de Pesquisa de Patofisiologia do Exercício, Hospital de Clínicas de Porto Alegre, Porto Alegre, RS, Brazil.
Karlyse Claudino
KC
Belli
Departamento de Hemodinâmica, Hospital Lifecenter, Belo Horizonte, MG, Brazil.
Ari
A
Mandil
Departamento de Hemodinâmica, Hospital Lifecenter, Belo Horizonte, MG, Brazil.
José Carlos Faria
JC
Garcia
Departamento de Hemodinâmica, Hospital Lifecenter, Belo Horizonte, MG, Brazil.
Rosanã Aparecida
RA
Araújo
Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
Amintas Fabiano de Souza
AF
Figueiredo
Programa de Pós-Graduação em Cardiologia, Fundação Universitária de Cardiologia, Porto Alegre, RS, Brazil.
Lucia Campos
LC
Pellanda
D000293:Adolescent; D000328:Adult; D000368:Aged; D000581:Amidohydrolases / Q000652:urine*; D015415:Biomarkers / Q000652:urine; D003324:Coronary Artery Disease / Q000503:physiopathology / Q000652:urine*; D003404:Creatinine / Q000652:urine; D003430:Cross-Sectional Studies; D005260:Female; D006333:Heart Failure / Q000503:physiopathology / Q000652:urine; D006801:Humans; D006973:Hypertension / Q000503:physiopathology / Q000652:urine; D016234:Kallikrein-Kinin System / Q000502:physiology; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D020840:Tissue Kallikreins / Q000652:urine*; D055815:Young Adult
D015415:Biomarkers; D003404:Creatinine; D020840:Tissue Kallikreins; D000581:Amidohydrolases