Aim To explore the production of adrenomedullin (ADM), changes and significance of ADM, ADM receptor system-calcitonin receptor like receptor (CRLR) and receptor activity modifying proteins (RAMP) mRNA in calcified vascular smooth muscle cells (VSMC). Methods Calcification of cultured rat VSMC was produced by incubation with β-glycerophos phate. Content of ADM released by VSMC was measured by radioimmunoassay (RIA). The amount of ADM, CRLR and RMAP mRNA was determined by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). The intracellular calcium content, alkaline phosphatase activity and cellular 45 Ca²⁺ uptake were determined. Results The content of calcium, 45 Ca²⁺ uptake and alkaline phosphatase activity in calcified VSMC increased by 118% , 174% and 7-fold (all P< 0.01), respectively, compared with control VSMC. Content of ADM in medium increased by 99% (P< 0.01). Furthermore, it was found that the levels of ADM, CRLR, RAMP 2 and RAMP 3 mRNA in calcified cells were elevated by 78% , 93.7% , 91.8% and 109.5 % (all P< 0.01), respectively, compared with control. The elevated levels of CRLR, RAMP 2 and RAMP 3 mRNA were positively correlated with ADM mRNA ( r = 0.83, 0.92 and 0.93, respectively, P< 0.01) in calcified VSMC. Conclusion Calcified VSMC generated an increased amount of ADM, up-regulated gene expressions of ADM, CRLR, RAMP 2 and RAMP 3, which suggested that changes of autocrine/paracrine function of vessel might be involved in the regulation of vascular calcification .