α1-Adrenoceptor Subtypes Differentially Couple to Growth Promotion and Inhibition in Chinese Hamster Ovary Cells

α1-Adrenergic Receptor Subtypes Differentially Control the Cell Cycle of Transfected CHO Cells through a cAMP-dependent Mechanism Involving p27

“…This study confirms an inhibitory effect of ␣ 1 -AR activation on the serum-promoted cell proliferation in a heterologous expression system and shows that the inhibitory effect is subtype-dependent and mediated through cAMP production. In agreement with our findings, Keffel et al (30) recently has reported that ␣ 1 -AR subtypes are differentially coupled to growth promotion and growth inhibition in CHO cells (30). However, Keffel et al (30) concluded that the opposite effects of ␣ 1 -AR subtypes on cellular growth are because of quantitative differences in the ERK isoforms in the MAPK signal transduction pathway.…”

“…In agreement with our findings, Keffel et al (30) recently has reported that ␣ 1 -AR subtypes are differentially coupled to growth promotion and growth inhibition in CHO cells (30). However, Keffel et al (30) concluded that the opposite effects of ␣ 1 -AR subtypes on cellular growth are because of quantitative differences in the ERK isoforms in the MAPK signal transduction pathway. Although we confirmed the subtype-dependent differential extent of MAPK activation that is previously reported by Keffel et al…”

“…PE, phenylephrine; Phent, phentolamine; CTX, cholera toxin. (30) in the serum-free conditions (data not shown), we also found that serum activates the MAPK pathway more dramatically than ␣ 1 -AR activation. In fact, as shown in Fig.…”

BML‐241 fails to display selective antagonism at the sphingosine‐1‐phosphate receptor, S1P3

“…CHO-K1 cells were passaged 1:10 every 2 or 3 days in F-12 Nutrient Mixture (Ham) with L-glutamine, supplemented with 100 U ml À1 penicillin, 100 mg ml À1 streptomycin and 10% foetal calf serum (FCS). CHO-K1 cells stably expressing a 1A -adrenoceptor were cultured as described previously (Keffel et al, 2000). Flp-In-CHO cells stably expressing the S1P 2 or S1P 3 receptor (see below) were passaged 1:5 every 2 or 3 days in F-12 Nutrient Mixture (Ham) with L-glutamine, supplemented with 100 U ml À1 penicillin, 100 mg ml À1 streptomycin, 313 mg ml À1 hygromycin B and 10% charcoalstripped FCS.…”

The role of Src homology 2 containing protein tyrosine phosphatase 2 in vascular smooth muscle cell migration and proliferation

“…FAK is strongly activated by integrin, growth factor receptors and G-protein receptor engagement and serves to integrate downstream signals in response to a variety of ligands and agonists [29] . In particular, FAK is an intermediate signal in VSMC migration and proliferation [30] . Fibroblast SHP2 is required for cell spreading, migration and focal adhesion.…”