Inhibition of chemically induced erythrodifferentiation in friends erythroleukemia cells by d,1-Propranolol

Dimethyl sulfoxide (2%), hexamethylene bisacetamide (4mM) and butyric acid (2mM) were potent inducers of erythrodifferentiation in Friend erythroleukemia cell lines, 5–18 and C19TK. Hydrocortisone (1μM) markedly inhibited dimethyl sulfoxide induced hemoglobin production in both 5–18 and C19TK cells. d,1-Propranolol (25–50μM) markedly inhibited both dimethyl sulfoxide and hexamethylene bisacetamide induced erythrodifferentiation in 5–18 cells but not in C19TK cells. Addition of either hydrocortisone or propranolol as late as 48 hrs after dimethyl sulfoxide addition still resulted in significant inhibition of hemoglobin synthesis in 5–18 cells. Although the mechanism of action of propranolol is not known, modulation of the β adrenergic receptor is apparently not involved since practolol failed to inhibit either dimethyl sulfoxide or hexamethylene bisacetamide induced erythrodifferentiation in 5–18 cells nor did isoproternol induce hemoglobin synthesis.