SEMIQUANTITATIVE REVERSE TRANSCRIPTION-POLYMERASE CHAIN-REACTION ANALYSIS OF MESSENGER-RNA FOR GROWTH-FACTORS AND GROWTH-FACTOR RECEPTORS FROM NORMAL AND HEALING RABBIT MEDIAL COLLATERAL LIGAMENT TISSUE

Growth factors and their receptors play an essential role in the devel opment, maturation, and response to injury of all tissues. A number of studies have explored the possibility of improving ligament healing w ith exogenous growth factors. However, limited data is available regar ding the endogenous growth factor network in ligaments on which any ex ogenous growth factors must impact. The purpose of this study was to a ssess the endogenous growth factor network with molecular techniques. By the sensitive reverse transcription-polymerase chain reaction techn ique, transcripts for a number of growth factors and receptors were de tected with RNA isolated from normal and healing rabbit medial collate ral ligament tissues. These include transforming growth factor-pi, ins ulin-like growth factors I and II, basic fibroblast growth factor, end othelin-l, and the receptors for insulin and insulin-like growth facto r II. Semiquantitative reverse transcription-polymerase chain reaction analysis of RNA from normal and scar tissues from the medial collater al ligament revealed that the levels of several transcripts were eleva ted in the scar tissue. It was not possible to confirm biological acti vity because of the hypocellularity of the tissues; however. the resul ts obtained indicate that the reverse transcription-polymerase chain r eaction approach to defining the endogenous growth factor-receptor phe notype is feasible, and further definition should contribute to the de velopment of rational approaches to exogenous therapy to improve heali ng.