Abstract
1. Aim. The biochemical characteristics of atrial natriuretic peptide receptors (ANP-R) derived from rat vascular smooth muscle (A-10 cell line) and central nervous system (CNS; olfactory bulb) tissue were compared. 2. Method and Results. ANP-Rs from each source were solubilized with 40 to 65% efficiency utilizing the nonionic detergent Lubrol-PX. Upon solubilization, the ANP-R from each source maintained the ability to bind125I-ANP(99-126) with a high affinity; Scatchard analysis indicated that the VSMC ANP-R displayed a Kd for the radioligand of approximately 10 p M, whereas the olfactory receptor possessed a Kd of about 165 p M. The Bmax values for the soluble VSMC and olfactory ANP-Rs were 285 and 30 fmol/mg protein, respectively. Competition binding studies indicated that the VSMC ANP-R bound ANP(99-126), ANP(103-126), and ANP(103-123) with similar affinities, whereas the olfactory ANP-R was much more sensitive to changes in the COOH-terminal structure of the competing peptide. The soluble ANP-Rs from VSMC and olfactory were chromatographically indistinguishable on phenyl-, DEAE-, and wheat germ agglutinin-agarose columns. However, the ANP-Rs could be distinguished using GTP-agarose; the olfactory ANP-R was capable of binding to the resin, whereas the VSMC ANP-R was not. 3. Conclusions. Coupled with other studies, these data suggest that the A10 VSMC ANP-R observed in this study may not be coupled to guanylate cyclase and may represent a receptor serving a clearance function, whereas a significant proportion of the olfactory CNS ANP-R appears to be associated with GTP-binding proteins, likely particulate guanylate cyclase, and probably represents a coupled form of the receptor.
Original language | English (US) |
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Pages (from-to) | 57-73 |
Number of pages | 17 |
Journal | Cellular and Molecular Neurobiology |
Volume | 9 |
Issue number | 1 |
DOIs | |
State | Published - Mar 1989 |
Externally published | Yes |
Keywords
- atrial natriuretic peptide (ANP)
- olfactory tissue
- soluble ANP receptors
- vascular smooth muscle cells
ASJC Scopus subject areas
- Cellular and Molecular Neuroscience
- Cell Biology