Angiotensin receptors and angiotensin I-converting enzyme in rat intestine

Journal Article · Sun Oct 01 00:00:00 EDT 1989 · American Journal of Physiology; (USA)

OSTI ID:5189058

Duggan, K A; Mendelsohn, F A; Levens, N R ^[1]

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1. Austin Hospital, Melbourne, Victoria (Australia)

The purpose of this study was to map the distribution of angiotensin II (ANG II) receptors and ANG I-converting enzyme (ACE) in rat intestine. ANG II binding sites were visualized by in vitro autoradiography using iodinated (Sar1, Ile8)ANG II. The distribution of ACE was mapped using an iodinated derivative of lisinopril. Male Sprague-Dawley rats were killed and the interior of the whole intestine washed with ice-cold saline. Segments of duodenum, jejunum, ileum, and colon were quickly frozen in a mixture of isopentane and dry ice. Twenty-micron frozen sections were thaw-mounted onto gelatin-coated slides, incubated with either ligand, and exposed to X-ray film. After exposure and subsequent development, the films were quantitated by computerized densitometry. ANG II receptors were most dense in the colon, followed by the ileum, duodenum, and jejunum. Within each segment of intestine, specific ANG II binding sites were localized exclusively to the muscularis. In contrast, ACE was present in both the mucosa and the muscularis. The colocalization of ANG II receptors and ACE may suggest a role for locally generated ANG II in the control of intestinal function. The luminal orientation of ACE in the mucosa of the small intestine may suggest that at this site ACE serves primarily to hydrolyze dietary peptides.

• OSTI ID: 5189058
• Journal Information: American Journal of Physiology; (USA), Vol. 257; ISSN 0002-9513
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ANGIOTENSIN
RECEPTORS
PEPTIDE HYDROLASES
TISSUE DISTRIBUTION
AUTORADIOGRAPHY
INTESTINES
IODINE ISOTOPES
MUSCLES
RATS
ANIMALS
BODY
CARDIOVASCULAR AGENTS
DIGESTIVE SYSTEM
DISTRIBUTION
DRUGS
ENZYMES
GASTROINTESTINAL TRACT
GLOBULINS
HYDROLASES
ISOTOPES
MAMMALS
MEMBRANE PROTEINS
ORGANIC COMPOUNDS
ORGANS
PROTEINS
RODENTS
VASOCONSTRICTORS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques