TABLE 2.

Amounts of lipid phosphorus recovered in membrane fractions from differentiating spermatogenic cells with respect to the amounts present in their corresponding total homogenates

	Light	Heavy	Extra Heavy	Pellet
	μg of lipid P/100 μg of P from TH
TCs	1.1 ± 0.1 (5.7%)	17.4 ± 1.4 (94.3%)	25.0 ± 4.7	36.5 ± 3.9
PtSs	0.9 ± 0.1 (2.3%)	21.7 ± 4.2 (97.7%)	39.5 ± 2.8	18.3 ± 5.9
RSs	1.0 ± 0.2 (5.3%)	18.8 ± 5.7 (94.7%)	31.5 ± 2.3	28.6 ± 3.1
LSs	1.5 ± 0.2 (7.0%)	19.6 ± 2.6 (93.0%)	23.4 ± 1.2	35.5 ± 1.1

Total spermatogenic cells (TC) were obtained from adult rat seminiferous tubules and pachytene spermatocytes, round spermatids, and late spermatids (PtSs, RSs, and LSs, respectively), were isolated therefrom. Total homogenates (TH) were prepared from each of the cell populations and subjected to membrane fractionation as illustrated in Fig. 1A. Lipids were extracted from each TH and from the membrane fractions of each cell population. The results compare the amount of lipid phosphorus (P) contained in each membrane fraction with respect to a fixed amount (100 μg) of lipid phosphorus present in the corresponding TH. Note that the lipid phosphorus recovered in the three membrane fractions plus pellets, added up, amounted on average to 80%, 80.4%, 79.9%, and 80% of the content in each of the initial TH from TCs, PtSs, RSs and LSs, respectively. Figures in parenthesis indicate the mole percent distribution of lipid phosphorus between the light and heavy fractions.