Adrenomedullin receptors in rat choroid plexus

• Published in: Neuroscience letters 2001-01, Vol.297 (3), p.167-170
• Main Authors: Kobayashi, Hideyuki, Shiraishi, Seiji, Minami, Shin-ichi, Yokoo, Hiroki, Yanagita, Toshihiko, Saitoh, Tomokazu, Mohri, Motohiko, Wada, Akihiko
• Format: Article
• Language: English
• Subjects: Adrenomedullin; Animals; Biological and medical sciences; Calcitonin gene-related peptide; Calcitonin Gene-Related Peptide - pharmacology; Calcitonin Receptor-Like Protein; Calcitonin receptor-like receptor; Cerebral circulation. Blood-brain barrier. Choroid plexus. Cerebrospinal fluid. Circumventricular organ. Meninges; Choroid plexus; Choroid Plexus - cytology; Choroid Plexus - drug effects; Choroid Plexus - metabolism; Cyclic AMP; Cyclic AMP - metabolism; Cyclic GMP - metabolism; Dose-Response Relationship, Drug; Fundamental and applied biological sciences. Psychology; In Vitro Techniques; Intracellular Signaling Peptides and Proteins; Male; Membrane Proteins - biosynthesis; Membrane Proteins - genetics; Nitroprusside - pharmacology; Peptides - genetics; Peptides - metabolism; Peptides - pharmacology; Rats; Rats, Sprague-Dawley; Receptor Activity-Modifying Proteins; Receptor-activity-modifying protein; Receptors, Adrenomedullin; Receptors, Calcitonin - biosynthesis; Receptors, Calcitonin - genetics; Receptors, Peptide - genetics; Receptors, Peptide - metabolism; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - biosynthesis; Signal Transduction - drug effects; Vertebrates: nervous system and sense organs
• ISSN: 0304-3940; 1872-7972
• DOI: 10.1016/S0304-3940(00)01706-7

To characterize transmembrane signaling of adrenomedullin (AM) in the choroid plexus, we studied the effects of AM on cyclic AMP (cAMP) and cyclic GMP (cGMP) levels as well as expression of mRNA for AM receptor in the rat choroid plexus slices. AM or calcitonin gene-related peptide (CGRP) increased cAMP (but not cGMP) level in a concentration-dependent manner, with AM being much more potently than CGRP. AM mRNA as well as calcitonin-receptor-like receptor mRNA and receptor-activity-modifying protein 2 mRNA, were highly expressed in the choroid plexus. Our biochemical and pharmacological studies may raise the possibility that choroid plexus secretes AM into the cerebrospinal fluid, and AM regulates choroid plexus function in an autocrine/paracrine manner via acting on AM-specific receptors.