Figure 3.

OGF was the specific opioid peptide involved in the growth inhibition of RTCFs. (A) The effects of various endogenous and exogenous opioids (10⁻⁶ M) on RTCF number for 72 hours. (B) RTCFs were treated with a polyclonal antibody specific for OGF (CO172), preimmune serum (IgG), or sterile water; antibodies and peptide were replaced daily. Cell counts were recorded at 72 hours. Data from the experiment in (A) represent the mean ± SE of at least 10 wells/group performed in triplicate. Data for the experiment in (B) represent the mean ± SE of at least two aliquots/well from at least three wells/group. Significantly different from respective controls at *P < 0.05 and ***P < 0.001.