Figure 7.

  Northern analyses of mRNA expression of osteogenic protein‐1 (OP‐1), bone morphogenetic protein‐3 (BMP‐3) and collagen type IV in tissue generated by 5 and 25 μg hTGF‐β2 reconstituted with collagenous matrix as carrier and harvested on day 30 and 90 after heterotopic implantation in the rectus abdominis muscle. Samples of 100/200 mg from duplicate specimens from the rectus abdominis on day 30 and 90 were pooled and the RNA extracted. Northern blot hybridizations were carried out with radioactively labelled probes to the indicated markers (shown in panels below each histogram), and the signals were quantified relative to γ‐actin blots by densitometric analysis. mRNA levels are expressed as relative densitometric units.