Long term effects of neonatal hypothyroidism on pituitary estradiol binding sites in the female rat

Two months after recovery from a perinatal hypothyroidism (PTU), the total amount of pituitary estradiol binding sites (EBS) was still dramatically reduced, but the actual concentration of EBS had returned to control levels.     

Cytochalasin D is able to mimic the effects of phalloidin on the rat liver

Summary Cytochalasin D induces a strong potassium release in the isolated perfused rat liver and leads to vacuolization of the liver parenchymal cells. These effects are similar to the action of phalloidin on the rat liver. Since phalloidin and cytochalasin act in a different way on microfilaments, it is suggested that any disturbance of the function of microfilaments can induce these effects.Acknowledgment. I thank Professor Th. Wieland for his interest in this investigation. The technical assistance of Iris Gilbert is very much appreciated.     

Cytochalasin D is able to mimic the effects of phalloidin on the rat liver

Cytochalasin D induces a strong potassium release in the isolated perfused rat liver and leads to vacuolization of the liver parenchymal cells. These effects are similar to the action of phalloidin on the rat liver. Since phalloidin and cytochalasin act in a different way on microfilaments, it is suggested that any disturbance of the function of microfilaments can induce these effects.     

The effects of 4 detergents on the respiration of mitochondria isolated from rat liver]

The effects of these four detergents (two non-ionic: Titron X100 and Tween 80, two ionic: sodium cholate and sodium dedeoxycholate) upon the respiratory intensities of mitochondria and upon the ADP/0 and respiratory control ratios were observed. At low concentrations and in the absence of exogenous ADP, non ionic as well as ionic detergents provoked a threefold (or fourfold) increase of the respiratory intensities of mitochondria. At higher concentrations, the four detergents were inhibitory for mitochondrial oxidations in the order: Triton X 100 greater than DOC greater than cholate greater than Tween 80. At increasing doses, the four detergents progressively decreased the phosphorylating capacities of mitochondria.     

Glucocorticoid and mineralocorticoid effects in rat liver and kidney

Zusammenfassung Die biochemischen Wirkungen von Aldosteron in der Rattenniere und Corticosteron in der Rattenleber wurden untersucht und der Mechanismus der Hormonwirkung diskutiert.     

Effect of p-coumaric acid on immature estrogen treated and cyclic female mice

Oral administration of p-coumaric acid to estrogen-primed immature female mice exerts neither estrogenic nor anti-estrogenic activity, but when it is administered to cyclic female mice in single dose at proestrus or in repeated doses, induces alteration in estrus cycle, ovarian and uterine weight and structure.     

Effect of p-coumaric acid on immature estrogen treated and cyclic female mice

Summary Oral administration of p-coumaric acid to estrogen-primed immature female mice exerts neither estrogenic nor anti-estrogenic activity, but when it is administered to cyclic female mice in single dose at proestrus or in repeated doses, induces alteration in estrus cycle, ovarian and uterine weight and structure.The authors wish to thank Dr S. C. Pakrashi and his associates of Medicinal Chemistry Department for isolating the compound. Thanks are also due for granting Senior Research Fellowship to P.P. and Junior Research Fellowship to S.N.K. respectively.     

Morphological and biochemical effects of ethylene on Tulips

Summary Tulip bulbs treated with ethylene at various concentrations, at different stages of development and during various lengths of time, exhibited various morphological abnormalities: open bud, stamen blasting, abnormal number of floral parts, increased number of second-year bulbs. These morphological changes were paralleled by rapid variations in the contents of proteins and RNAs, and a slow, yet noticeable, increase of the DNA content of flower buds.     

Influence of pinealectomy on serum estrogen and progesterone levels in blind-anosmic female rats

Summary Previous studies show that the suppression of gonadal function in blind-anosmic rats is dependent on the pineal gland. The present results demonstrate that in young female rats both the pineal gland and dual sensory deprivation have additional independent antigonaldal effects.This work was partially supported by state institutional funds and by NSF grant No. PCM 74-06276-276-A02. The radioimmunoassays of the steroids were carried out with the aid of the Radioimmunoassay Core which is supported by USPHS grant No. 1T30 HD-10202. We also thank Constance Stahl for typing assistance.     

CNS stimulation effect on the sexual maturation of the female rat

Summary In the immature rat, CNS stimulants administration to pregnant mare serum gonadotropin (PMSG) primed rats resulted in significant (p<0.01) ovarian and uterine hypertrophy when compared to animals treated with PMSG only. Meanwhile precocious puberty was produced by pentylenetetrazol treatment alone. The results of this experiment may indicate that administration of CNS stimulants has a specific action on the release of endogenous gonadotropin.Supported by NIH grant no. RR 8111.National Institute of Health, MBS Graduate Trainee.     

Effects of female sex hormones on polyamine-oxidizing enzyme activities and polyamine concentrations in immature rat uterus and liver

17-estradiol (E₂) and progesterone (P) treatment of immature female rats (10 g/100 g body weight) respectively resulted in 1.38-fold (p<0.02) and 1.42-fold (p<0.02) increase in the uterine polyamine oxidase activity, and 2.45-fold (p<0.001) and 1.43-fold (p<0.02) increase in the uterine diamine oxidase activity, as compared to the controls. E₂ caused a 5-fold (p<0.05) and a 1.36-fold (p<0.05) increase in putrescine and spermidine concentration respectively in rat uterus. Increases of 1.7-fold (p<0.02) and 1.6-fold (p<0.05) in putrescine and spermine concentration were determined in the P-treated uterus, as compared to the controls. The spermidine/spermine ratio, which is regarded as an index of growth rate, was higher in the E₂-treated uterus and lower in the P-treated uterus than in the control uterus. No statistically significant hormonal effects were estimated in the immature liver. The data reported suggest the possibility of an involvement of polyamine-oxidizing enzymes in the modulation of polyamine concentrations in rat uterus by the female sex hormones.     

Effect of actinomycin D or puromycin on microsomal testosterone hydroxylase activity enhanced by testosterone in female rat liver

Summary The injection of testosterone propionate for 4 successive days into female rats resulted in an increase of the in vitro conversion of the hydroxylated testosterones from testosterone by the hepatic microsomal, fraction, but no change in the content of microsomal cytochrome P-450 occurred. Actinomycin D or puromycin, which was administered for 4 days with injections of testosterone propionate, prevented the enzyme induction.     

Effect of propranolol on various parameters of estrogen stimulation in the rat uterus

Summary Pretreatment with propranolol does not modify the estrogen-induced uterine eosinophilia, the water imbibition effect, nor the increase in uterine RNA and protein content. This confirms the independence of these parameters from the estrogen-induced early increase in uterine cAMP, since, when observed, the latter is suppressed by propranolol pretreatment.Acknowledgments. This work was supported by a contract of the Ministère de la Politique Scientifique, within the framework of the Association Euratom—University of Brussels—University of Pisa, and by grant 2015 from the Oficina Técnica de Desarrollo Científico y Creación Artística of the University of Chile.