Expression of angiotensin II receptors in aldosterone-producing adenoma of the adrenal gland and their clinical significance

Abstract

The expression of angiotensin II type 1 receptor (AT₁R) and angiotensin II type 2 receptor (AT₂R) in aldosterone-producing adenoma (APA) of the adrenal gland was detected, and their relationship with clinical indexes of APA was analyzed. The mRNA expression of AT₁R and AT₂R in 50 cases of APA and tissues adjacent to tumors and 12 cases of normal adrenal tissues was detected by using reverse transcriptase polymerase chain reaction (RT-PCR). The expression of AT₁R and AT₂R proteins in paraffin-embedded slices of tissue was detected by immunohistochemistry. The expression of AT₁R in adenoma, tissues adjacent to tumor, and normal tissues of the adrenal gland showed no significant differences. The expression of AT₂R in APA tissue was lower than that in normal adrenal gland tissues (P<0.05). Correlation analysis of the mRNA expression level of AT₂R and clinical data from patients demonstrated that AT₂R expression was negatively related to plasma aldosterone concentration (PAC) (r=−0.467, P<0.05), but positively related with plasma renin activity (PRA) (r=0.604, P<0.05). It is concluded that down-regulation of the AT₂R expression is possibly related with the tumorigenesis of APA.

Keywords

adrenal gland / aldosterone / adenoma / angiotensin II receptor

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