A new enzymatic method for determination of serum choline-containing phospholipids

A new enzymatic method is presented for the determination of serum choline-containing phospholipids with a combined enzymatic method using phospholipase D (from Streptomyces species), choline oxidase (from Arthrobacter species) and peroxidase. The method is reproducible, and the results correlate well with those obtained by the conventional digestion method (Hoeflmayr, J. and Fried, R. (1966) Med. Ernaehr. 7, 9-10). The method affords better specificity, requires a smaller quantity of the sample and shorter time than those previously reported, and has excellent precision.

[Changes in adrenal gland and thymus induced by sex steroid administration in newborn rats (author's transl)]

Testosterone, dehydroepiandrosterone (DHEA), progesterone, estradiol-17beta, estrone, estriol, 2-hydroxyestradiol-17beta, 2-hydroxyestriol, deoxyestrone and diethylstilbestrol were injected s.c. in a dose of 0.5 mg each into newborn rats on the first day of life, and changes in the adrenal gland, thymus and spleen were examined 3 days later. Increase in the body weight during the 3 days was less in rats treated with DHEA, 2-hydroxyestriol and deoxyestrone, as compared with that in controls. Development of the thymus was significantly impaired in rats injected with various kinds of sex steroids, except progesterone and diethylstilbestrol. Reduction of the spleen weight by sex steroid treatment was not marked. The weight of adrenal gland decreased in rats injected with DHEA and progesterone, while the weight increased in those given estrone and diethylstilbestrol. Estrogens, particularly estriol, induced a marked increase in adrenal corticosterone content, while 2-hydroxyestriol caused only slight elevation and 2-hydroxyestradiol and deoxyestrone had no influence on the content. Suppressive effect of cortisol on the adrenal gland of newborn rats was slightly, but significantly, lessened by estriol treatment. From the results, physiological role of estriol and DHEA in adrenal secretion was discussed.

[Postnatal development of the adrenal gland in the rat (author's transl)]

Postnatal development of adrenocortical function of rats was studied. During the first week after birth the increase in adrenal weight was very slight. Consequently, the relative weight of the gland per body weight decreased progressively during the postnatal 14 days. However, adrenal corticosterone concentration showed a gradual elevation over this period of postnatal days. Adrenal corticosterone response to ether stress did not appear in male rats at 12 days of age, but a distinct response was observed in female ones at the same age. A sex difference in the duration of the stress-nonresponsive period is likely to exist in newborn rats. In accord with the stress-nonresponsive period, the thymus-lymphatic system showed a marked development. The pattern of circadian periodicity of plasma corticosterone levels in 21-day-old rats was somewhat different from that in adult rats. Peak value of the corticosterone rhythm was attained at 0300 in the infant rats. A sex difference was again noticed in the evening rise of plasma corticosterone level in these infant rats: the rise was steeper in females than in males. A significant circadian periodicity was observed in female rats at 14 days of age, but the periodicity was equivocal in male ones at the same age.

[Atrophy of adrenal gland and thymus following cortisol treatment in newborn rats (author's transl)]

Effects of neonatal treatment with cortisol on the mortality, growth rate, the weight of thymus, spleen and adrenal gland, blood lymphocyte counts and stress responses were examined in the rat. In rats treated with 1 mg cortisol the survival rate was only 13 percent, and in those given 0.75 mg the rate was 47 percent. Large doses of cortisol produced "wasting syndrome" and the animals died during a period from 5 to 13 days after the injection. Over the first week the body weight did not increase in rats injected with cortisol in doses of 1 and 0.75 mg. A marked atrophy of the thymus and a great reduction of the blood lymphocyte counts were observed in rats treated with large doses of cortisol. The development of spleen was temporarily inhibited. The adrenal gland was remarkably atrophied: the gland weight at 21 days of age was similar to that at birth and only 22 percent of the control value. In rats injected with 0.5 mg cortisol plasma corticosterone response to ether inhalation was not different from that of normal controls at 21 days of age. However, rats treated with 0.75 and 1 mg cortisol did not show plasma corticosterone response on exposure to a strange environment. The effect of several kinds of corticoids was also examined. Dexamethasone and betamethasone caused a marked atrophy of the thymus and spleen. Cortisol and deoxycorticosterone produced a large decrease in the adrenal corticosterone content. The effect of exogenous corticosterone was less in extent as compared with that of cortisol.

[Effect of acute cold exposure on blood composition in rats treated with 6-Hydroxydopamine (author's transl)]

Rats injected with 6-hydroxydopamine (6-OHDA) into the lateral ventricle showed greater elevation in plasma FFA and beta-hydroxybutyrate and significant decrease in blood sugar and lactate following acute cold exposure at -10 degrees C for 2 hours. Changes in the blood composition induced by the cold exposure in rats treated with 6-OHDA intravenously were not different from those observed in control rats. Adrenomedullectomized rats treated with 6-OHDA responded to the cold exposure with rather marked elevation in plasma FFA and beta-hydroxybutyrate. These results were discussed from the view-point of compensatory changes in metabolic regulation in the absence of norepinephrine.

Effects of norepinephrine and thyroxine on the turnover rate of plasma free fatty acids

Effects of norepinephrine infusion on rectal temperature, plasma free fatty acids (FFA) concentration and its turnover rate were studied in rats treated chronically with norepinephrine, thyroxine, or both. Chronic treatments with these hormones resulted in greater increases in rectal temperature and FFA turnover rate in response to norepinephrine as compared with the alterations in controls. Norepinephrine-induced elevation of FFA concentration was smaller in norepinephrine-treated and norepinephrine plus thyroxine-treated rats than in controls, and in thyroxine-treated rats the elevation was similar to that of controls. The regression coefficient of FFA concentration of its turnover rate was greater in all the treated groups than in controls although positive correlations were observed among both variables in the former and the latter. From the results it was inferred that the greater increase in removal of plasma FFA was produced by norepinephrine in parallel with the greater increase in rectal temperature by norepinephrine in rats treated with norepinephrine or thyroxine than in the controls. The effects of norepinephrine infusion were also studied in surgically thryoidectomized rats. In thyroidectomized rats adapted to warm or cold, the smaller increases in rectal temperature and ithe turnover rate of plasma FFA were induced by norepinephrine as compared with the changes in intact rats. The alterations in FFA concentration produced by norepinephrine were less in warm-adapted thyroidectomized rats and greater in cold-acclimated thyroidectomized rats than in respective controls.

Ultrastructural study of human myeloma cells in relation to its function

The ultrastructure of neoplastic plasma cells from a patient with prolonged multiple myeloma was studied in relation to its function, that is, the secretion of immunoglobulin light chain. Peroxidase-labelled antibodies, each monospecific to its immunoglobulin component chain, were used to localize intracellular immunoglobulin within myeloma cells under the electron microscope. By this method, only the kappa type light chain was detected within myeloma cells in bone marrow tissue of this patient, indicating that the occurrence of free kappa type light chains in serum and urine was due to the cessation of heavy chain synthesis within the myeloma cells. The kappa chain was demonstrated as conspicuous electron-dense precipitates in ergastoplasm, its cisternal space, external layer of nuclear membrane, and ribosomes associated with ergastoplasm and nuclear membrane. No immunoglobulin was demonstrated in an atypical Golgi complex, an organelle which is ordinarily engaged in protein synthesis. Numerous crystalline structures and similar inclusion bodies found in myeloma cells appeared to have arisen from the Golgi area, but they did not ever react with the peroxidase label. Discharge of the kappa chain from the cell seems to be carried out through cell fragmentation, possibly caused by progressive distension of the ergastoplasmic cavity.