Molecular composition of the phosphatidylcholines produced by the phospholipid methylation pathway in rat brain in vivo.

We examined the formation in vivo of molecular subspecies of brain phosphatidylcholine (PC) via the phospholipid-methylation pathway. [3H]Methionine was infused into a lateral cerebral ventricle, and 3H-labelled PC was isolated from brains of rats 0.1-18 h after the infusions. Three major subspecies of this PC, differing in their fatty acid compositions, were separated on silver-impregnated t.l.c. plates, and the proportions of radioactivities in these three PC fractions were determined. The results indicate that newly-formed PC synthesized by methylation of phosphatidylethanolamine at 0.1 h after [3H]methionine contains a significantly higher proportion of polyunsaturated subspecies (i.e. those with six or four double bonds) than does PC obtained later times after injection of [3H]methionine. This change in the composition of 3H-labelled brain PC occurs gradually and is not due to an influx of radioactive PC from the periphery. Our data suggest that polyunsaturated PC (hexaenes and tetraenes) produced in the brain by methylation of phosphatidylethanolamine turns over faster than does that containing more-saturated fatty acids.

[Hormonal status and the clinical course of ovarian cancer]. / Gprmonal'nyi status i klinicheskoe techenie raka iaichnikov.

PIP: As a rule, patients with ovarian cancer do not display any important endocrine disturbances. The authors studied the cases of 104 of these patients: 19 had benign tumors, 6 intermediate tumors, 6 had 1st stage ovarian cancer, 7 3rd stage cancer, 54 4th stage cancer. The remaining patients had a recidivist ovarian cancer. All patients with primary cancer had the uterine hormonal secretions studied. The results indicated the absence of specific changes in the uterine secretion of steroid hormones and in the level of follicle stimulating hormone and luteinizing hormone in the serum. This was true for all patients with benign, intermediate and malignant ovarian tumors. The duration of remission in the patients with 4th stage of cancer was greater when the estrogen stimulation and the level of androgen secretion were increased.^ieng