As a group teleost fish exhibit glucose intolerance, which leads to persistent hyperglycemia and coincides with transient hyperinsulinemia. Insulin−deficiency cannot explain this phenomenon as teleost fishes normally exhibit high plasma insulin levels, likely due to evolutionary diet adaptation or the peripheral utilization of glucose (Moon, 2000). However commonly utilized fish cell culture techniques use classical media based on mammalian physiology. Of interest in this study, myogenic precursor cells (MPCs) from several teleost species are currently cultured in a high glucose medium similar to that used for the culture of mammalian myosatellite cells (MSCs) and the immortalized mammalian cell line C2C12. To assess the impacts of glucose concentration on cultured cells, [i]Oncorhynchus mykiss[/i] (rainbow trout) MPCs were cultured in high or low glucose media over an 8−day period. Samples were collected at specific myogenic stages: D2, myoblasts; D4, differentiating myoblasts; and D8, myotubes. Preliminary results show that cell proliferation, demonstrated by PCNA expression, did not change significantly in response to glucose levels. However, myogenin expression was increased, indicating increased cell differentiation, in the low glucose media. While both media appear to be suitable for the culture of teleost primary cells, low glucose media may be used to enhance cell differentiation stimulated by incubation with 2% FBS.