1. We investigated the characteristics and expression of transforming growth factor-beta (TGFbeta) receptor subtypes on vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats. 2. TGFbeta binding assays revealed that VSMC from SHR showed higher number and affinity of TGFbeta receptors than cells from WKY rats. 3. The affinity labelling with [125I]-TGFbeta1 revealed the presence of TGFbeta receptor subtypes with molecular sizes of 280, 85, 70 and 60kDa on VSMC from both strains at high cell density. The abundance of the 85kDa receptor subtype was greater in VSMC from SHR than cells from WKY rats. The 85kDa receptor subtype was not detected on VSMC from both strains at low cell density. 4. These results suggest distinct expression of TGFbeta receptor subtypes on VSMC from SHR and WKY rats, which may account for the exaggerated proliferative response of VSMC from SHR to TGFbeta.