A colorimetric method for the determination of deoxyribonucleic acid in adipose tissue.

A method is described for measuring the deoxyribonucleic acid (DNA) content of small samples of adipose tissue or free fat cells. Lipids and acid-soluble nucleotides are first removed by extraction with a cold diethyl ether - ethanol mixture containing 10 per cent. ml V of trichloroacetic acid. DNA is then measured by hydrolysing the nucleoprotein residue in a 5 per cent. solution of trichloroacetic acid at 90 QC for 20 min, followed by treatment with p-nitrophenylhydrazine and measurement of the hydrazone at 560 nm. Several aspects of the method have been critically examined in order to determine the optimum conditions. The method is satisfactorily reproducible

Investigations into the effects of cyclical rhythm and hormonal contraception on serum fat-mobilizing activity, glycerol, cholesterol and blood glucose.

The effects were investigated of cyclical rhythm and hormonal contraception on serum fat-mobilizing activity, glycerol, cholesterol and whole blood glucose during 2 menstrual cycles in a group of normally menstruating young women and a second group of young women using hormonal contraception. A control group of normal young men was also investigated. There was no evidence of any change in mean level of any of the parameters measured, among the follicular, ovulatory and luteal phases. No cyclical pattern was discernable in the male subjects. The mean value for serum cholesterol concentration in women using hormonal contraception was higher than the value for the untreated human female group. The overall mean value for serum glycerol concentration in the women was significantly (0.01 > P > 0.001) higher than the mean value obtaining in the men