Figure 4.

Unsaponifiable fraction C1 exerts a different action on MEK1/2 and ERK1/2 activity in response to insulin in HTC cells. HTC cells were treated with 25 and 50 μg ml⁻¹ of C1 extract for 6 h (A) and 21 h (B) then the stimulated with insulin for 5 min before lysates were prepared. The cells were lysed and 20 μg of SDS-lysis protein extract were used for western blot analysis as described in the Materials and Methods section. Proteins immunoreactive to antibodies raised against the phosphorylated forms of ERK1/2 (p-ERK1/2) and PKB/Akt (p-Akt) were revealed by enhanced chemiluminescence as described in the Materials and Methods section. The non-phosphorylated proteins were revealed on stripped membrane as loading controls. Results are representative of three separate determinations.