Acetate utilization by the isolated perfused guinea-pig mammary gland

Acetate uptake by isolated perfused guinea-pig mammary glands was approximately 1.0 mg g-1 h-1 when perfusate acetate concentrations were in the physiological range (5-11 mg/100 ml plasma). At perfusate concentrations below this range (mean 3.62 mg/100 ml plasma) the uptake was not significantly different, but in one experiment in which the mean acetate concentration was 14.5 mg/100 ml plasma the uptake was markedly elevated. Radioactivity from Na (1-14C) acetate was incorporated into CO2 and milk and tissue fat, being largely present in C16 and C18 fatty acids. The guinea-pig is atypical of non-ruminants and similar to ruminants in respect of the blood concentration and mammary utilization acetate.