Cardiac myocytes were obtained from neonatal rat heart and cultured.HSV1-tk

chosen as the reporter gene

was inserted into adenovirus vector(Ad5-tk)

and the recombinant adenovirus infected neonatal cardiac myocytes with multiplicity of infection(MOI) of 20

40 and 80.MTT assay was used to detect the viability of infected cardiac myocytes

and semi-quantitative reverse transcriptase polymerase chain reaction(RT-PCR) was applied to determine HSV1-tk mRNA expression in the infected cells.The accumulation of 125I-FIAU into infected cardiac myocytes was detected as uptake rate.The survival rate of infected cells had negative correlation with time

and it decreased with higher viral multiplicity of infection(MOI).After transferred for 24 h

the cardiac myocytes showed significant expression of HSV1-tk mRNA

while the control groups showed negative.Moreover

the exogenous gene expression in the infected cells at MOI 40 was significantly higher than in the ones at MOI 20(P<0.01).The cardiac myocytes infected with increasing titer of Ad5-tk showed positive correlation between uptake rate and time

and the uptake rate of 125I-FIAU in the MOI 40 group was significantly higher than all the other groups(P<0.01).The HSV1-tk reporter gene could be transferred into the neonatal cardiac myocytes successfully with adenovirus vector

and encoded for HSV1-TK catalyzing phosphorylation so as to accumulate the marker substrates 125I-FIAU.The uptake rates

correlated to the uptake time

were the highest with transferred titer 40 at all the time points.This provides some cellular evidence for cardiac imaging of reporter gene in vivo.