Methadone and brain development

Summary The effect of maternally administered methadone hydrochloride (5 mg/kg) on brain development of off-spring treated during gestation and/or lactation was studied in 21-day-old rats. Animals treated during gestation or lactation were the most severely affected, with reductions in brain weights (12% and 30%,respectively), and DNA values (50% and 34%, respectively) observed.The assistance of Eileen J. Zagon is gratefully acknowledged. This research was supported in part by American Cancer Society grant PDT-27B and NIDP grant DA01618-01.     

Effects of temperature on the development of scutellar bristles

Résumé Chez la Drosophile, le troisième stade larvaire s'avère Être la principale période durant laquelle la température exerce une influence sur la formation des poils. Il semble toutefois probable qu'après le début de la pupation la température a un effet sur la localisation des poils surnuméraires. Une interaction chromosomale négative, ayant un effet sur le nombre des poils scutellaires, s'expliquerait par le processus de développement.     

Effects of tranylcypromine and pargyline on brain tryptamine

Summary Tranylcypromine produces behavioral excitation while pargyline produces depression. Tranylcypromine increased brain tryptophan which led to an accumulation of tryptamine. The levels of tryptamine after tranylcypromine were found to be 3 times those found after pargyline.This work was supported in part by U. S. Public Health Service Grants NS-12759 and AA-2696, State of Illinois Department of Mental Health, the Psychiatric Services Branch, Province of Saskatchewan, and the Medical Research Council of Canada, who have provided continuing financial support.Acknowledgments. We thank Dr B. A. Davis for synthesizing the deuterated internal standards, Dr D. A. Durden for supervising the mass spectrometric analyses, and Mr H. Miyashita, Mr N. F. Binder and Miss E. E. Johnson for skilled technical assistance.     

Effects of ovarian steroids on superoxide dismutase activity in the rat brain

The levels of manganese superoxide dismutase (MnSOD) and copper-zinc superoxide dismutase (CuZnSOD) were determined in appropriate subcellular fractions prepared from whole brain homogenates of cycling and long-term (3 week) ovariectomized (OVX) Wistar rats, and were compared to the levels found in corresponding samples prepared from OVX rats treated with progesterone (P) or estradiol 17B-benzoate (EB). The activity of both SODs was steady during the estrous cycle, except at proestrus, when MnSOD activity was elevated significantly. Bilateral ovariectomy resulted three weeks later in an increase of the MnSOD activity even higher than that recorded at proestrus. High post-castration MnSOD activity was lowered profoundly by exogenous P (2 mg) or EB (0.5 g), given s.c. to OVX animals 2 h or 24 h before sacrifice. Neither removal of the ovaries nor the hormone treatments affected the activity of CuZnSOD. These results suggest suppressive effects of ovarian steroids on MnSOD activity in the rat brain.     

The effect of phenylthiocarbamide (PTC) on mouse brain development

Summary PTC-when dispensed during the whole fetal development-causes a disturbance of brain development in new born mice. This disturbance is manifested by a reduction of the cell number, a reduced protein content and a reduced activity of acetylcholinesterase in the brain.     

Glutamine synthetase activity during mouse brain development

The specific activity of glutamine synthetase (GS) in mouse brain was 2-fold higher in the olfactory bulbs than in other regions. After birth, the specific activity of GS increased more rapidly in medulla oblongata and in olfactory bulbs, than in cerebral and cerebellar cortex. The activity of GS in primary cultures of brain hemispheres increased more slowly than in homogenates of whole brains. However, when astroblasts were treated in vitro with glucocorticoids or mouse brain extracts, GS activity reached 4 times the level measured in the homogenate of an adult mouse brain. We conclude that levels of GS activity may relate to the maturation of astrocytes, and propose that GS may be used as a marker of astrocytic maturation.     

Glutamine synthetase activity during mouse brain development

Summary The specific activity of glutamine synthetase (GS) in mouse brain was 2-fold higher in the olfactory bulbs than in other regions. After birth, the specific activity of GS increased more rapidly in medulla oblongata and in olfactory bulbs, than in cerebral and cerebellar cortex. The activity of GS in primary cultures of brain hemispheres increased more slowly than in homogenates of whole brains. However, when astroblasts were treated in vitro with glucocorticoids or mouse brain extracts, GS activity reached 4 times the level measured in the homogenate of an adult mouse brain. We conclude that levels of GS activity may relate to the maturation of astrocytes, and propose that GS may be used as a marker of astrocytic maturation.     

Maternal vitamin A restriction alters biochemical development of the brain in rats

Summary The biochemical development of the fetal brain in relation to maternal vitamin A restriction was studied in rats. The vitamin A status of pregnant rats was varied by supplying low, medium and adequate amounts (6, 40, and 100 g retinol/day/kg body weight, respectively) of vitamin A during pregnancy and suckling. The maternal vitamin A restriction caused an altered brain development in terms of tissue weight, DNA, RNA and protein levels, and biosynthesis of DNA and protein from [³H]-thymidine and [³H]-leucine, respectively. A dose-dependent effect of maternal vitamin A restriction on the metabolism of DNA, RNA and protein was noticed in the developing fetal brain of rats.     

Effects of thyroid state on brain stem responses to iontophoretic noradrenaline

Summary Responses to iontophoretic NA were increased in hyperthyroid rats and decreased in hypothyroid animals. No effect was observed on acetylcholine and glycine responses tested in the same way.This work was aided by grants from Consejo de Desarrollo Cientifico y Humanistico U.C.V. and CONICIT proyecto 51.26.SI-086.     

Changes in composition of etheric lipids during brain development

Résumé On a étudié les lipides éthériques dans la capsule interne, la région interlobaire et la substance blanche du lobe pariétal et temporal. On a constaté qu'vant la myélinisation la concentration des ces lipides est supérieure dans la capsule interne tandis qu'après le lobe temporal présente la plus haute concentration par rapport aux autres régions étudiées. Ces fluctuations expriment probablement l'instabilité lipidique des membranes cellulaires se trouvant à l'extérieur de la myéline.     

Effects of lithium chloride on peripheral acetylcholine release and brain acetylcholine levels in the guinea-pig

Summary Lithium chloride administered acutely or chronically to guinea-pigs had no effect on brain level of acetylcholine or on peripheral release of acetylcholine from longitudinal muscle of the ileum. The results suggest differences between in vitro and in vivo action of lithium.To whom correspondence should be addressed.     

Maternal vitamin A restriction alters biochemical development of the brain in rats.

The biochemical development of the fetal brain in relation to maternal vitamin A restriction was studied in rats. The vitamin A status of pregnant rats was varied by supplying low, medium and adequate amounts (6, 40, and 100 micrograms retinol/day/kg body weight, respectively) of vitamin A during pregnancy and suckling. The maternal vitamin A restriction caused an altered brain development in terms of tissue weight, DNA, RNA and protein levels, and biosynthesis of DNA and protein from [3H]-thymidine and [3H]-leucine, respectively. A dose-dependent effect of maternal vitamin A restriction on the metabolism of DNA, RNA and protein was noticed in the developing fetal brain of rats.     

Effects of centrophenoxine,piracetam and hydergine on rat brain lipid peroxidation

Summary The cerebral insufficiency improvers centrophenoxine, piracetam and hydergine were tested for their effect on lipid peroxidation of rat brain homogenates, both in vitro and in vivo. There was no effect either in vitro or after chronic 8 week dosing of animals.     

Effects of progesterone and estradiol benzoate on superoxide dismutase activity in the brain of male rats

The activities of mitochondrial, manganese-containing superoxide dismutase (MnSOD) and cytoplasmic, copper-zinc-containing superoxide dismutase (CuZnSOD) were measured in subcellular fractions of whole brain homogenates prepared from intact and gonadectomized (GDX) male rats, untreated or treated subcutaneously (sc) with a single dose of 2 mg progesterone (P) and/or 5 g estradiol benzoate (EB). Neither MnSOD nor CuZnSOD was affected by the removal of the testes. Similarly, CuZnSOD activity was steady following systemic administration of P and/or EB to intact and GDX animals 2 h or 24 h prior to sacrifice. On the other hand, both P and EB suppressed MnSOD in the brain of either intact or GDX rats. These results suggest involvement of P and EB in the control of MnSOD activity in the brain of male rats.