Expression of angiotensin I-converting enzymes and bradykinin B-2 receptors in mouse inner medullary-collecting duct cells

Author(s)

Quinto, Beata Marie Redublo ; Andrade, Maria Claudina Camargo de ; Ronchi, Fernanda Aparecida ; Santos, Edson Lucas ; Correa, Silvana Aparecida Alves ; Shimuta, Suma Imura ; Pesquero, João Bosco ; Mortara, Renato Arruda ; Casarini, Dulce Elena ^[9]

• Document type: Journal article
• Source: International Immunopharmacology; v. 8, n. 2, p. 254-260, Feb. 2008.
• Field of knowledge: Health Sciences - Medicine

Abstract

We described in mouse inner medullary-collecting duct cells (mIMCD-3) the somatic and the N-domain ACE synthesis and its interaction with the kallikrein-kinin system co-localized in the same cells. We purified two ACE forms from culture medium, M1 (130 kDa) and M2 (N-domain, 60 kDa), and cellular lysate, C1 (130 kDa) and C2 (N-domain, 60 kDa). Captopril and enalaprilat inhibited the purified enzymes. The immunofluorescence studies indicated that ACE is present in the membrane, cytoplasm and in the cell nucleus. Kinin B1 and B2 receptors were detected by immunofluorescence and showed to be activated by BK and DesR9 BK, increasing the acidification rate which was enhanced in the presence of enalaprilat. The presence of secreted and intracellular ACE in mIMCD-3 confirmed the hypothesis previously proposed by our group for a new site of ACE secretion in the collecting duct. (AU)

• FAPESP's process: 02/13290-2 - Angiotensin I: converting enzyme isoform (90 kDa), potential genetic marker of hypertension: processing, molecular and functional characterization, and genetic segregation
• Grantee: Dulce Elena Casarini
• Support Opportunities: Research Projects - Thematic Grants