Cellular receptors of gonadotropic hormones. Immunocytochemical evidence in rat testicle]

We have performed topical applications of HCG and LH on fixed paraffin-embedded sections of adult rat testes. Thereafter, immuno-cytochemical demonstration of the peptides was carried on and demonstrated that HCG and LH specifically bound to the cell membrane of Leydig cells. This technique is highly reproductible provided that adequate fixation (with formalin containing fixatives) as been performed.     

Mise en évidence par le cryodécapage de lomasomes dans la basidiospore de Hypholoma fasciculare (Huds. ex Fr.) Kummer

Summary Lomasomes were shown to be present in mature basidiospores of Hypholoma fasciculare using the freeze-etching technique. Grooves in the plasmalemma were also generally observed. It is suggested that lomasomes are related to the elaboration of the chitinous spore wall and, in accordance with the views of Campbell, plasmalemma grooves are connected with the melanisation of its outer parts.     

Interactions between a progestational derivative (norethisterone acetate) and ethinyl estradiol on urinary elimination of neurophysin, ocytocin, and vasopressin and on the blood level of neurophysin I and II in normal human beings

Neurophysin 1 (a peptide associated with antidiuretic homone, ADH), ADH, and oxytocin were measured in serum or urine of 3 men who took 10 mcg ethinyl estradiol with 5 mg norethisterone acetate twice daily for 6 days and in 3 who took the estrogen only. Neurophysin in plasma was determined by radioimmunoassy, and individually by starch gel electrophoresis, extraction, and assay. Total urine neurophysin was measured by radioimmunoassy. ADH and oxytocin were quantitated by column chromatography and radioimmunoassy. With both steroids, there was no change in neurophysin, ADH, or oxytocin. Ethinyl estradiol alone increased urinary neurophysin from 112.3 to 595 ng/hour (n.s.), oxytocin from 41-132 ng/hour (p less than .005), and ADH from 9.7-57.2 ng/hour (p less than .01). As in pregnant women compared to normal women, estrogen treatment stimulated plasma neurophysin 1 more than neurophysin 2 in these subjects. These results confirm those found in rats.     

In vivo assay of antisomatotropic activity of somatostatin and two of its analogs]

Somatostatin (Growth hormone release inhibiting hormone or somatotrophin-release inhibiting factor) and its analogues can be measured in vivo by inhibiting the pentobarbital induced growth hormone release in male rats. Experimental conditions must be carefully defined to become optimal.     

Effect of an ovine pineal gland extract on prolactin release in vitro]

Defatted ovine pineal powder is submitted to acetic acid extraction followed by chromatographic separation. The extracted material and one of the two separated fractions inhibit the secretion of PRL by pituitary cells in monolayer culture. Both basal and TRH stimulated secretions are reduced.     

Gonadocrinin-like activity of the peritoneal fluid during the menstrual cycle in the normal female

Peritoneal fluid formation and composition is under the dependence of the ovarian function. Collection of these fluids was performed by laparoscopy in normal cycling women. After absorption of the steroids, they were tested on monolayer pituitary cell cultures in order to study the influence on gonadotrophin release. LH secretion was stimulated through cell the menstrual cycle without any cycling variations. FSH secretion was also increased, excepted in the immediate post-ovulation period. Thus the Peritoneal fluid contains, as follicular fluid, substances with gonadocrinin- and inhibin-like activity. Gonadocrinin activity was not correlated with estradiol and progesterone levels in serum and peritoneal fluid.     

The red algal-higher fungi phylogenetic link: the last ten years

The review of the red algal theory for ancestry of Ascomycetes and Basidiomycetes published 10 years ago by the author is updated. Criticisms are answered and new data are discussed. The production of choline sulfate, lenthionine and lanosol are added to the biochemical similarities between red algae and higher fungi. Distribution of polyols is shown to be in favour of the origin of higher fungi from parasitic red algae. As predicted, NADP-linked glutamate dehydrogenase has been found in red algae, and additional reports of chitin in various algae have been published. New supporting data come from the ultrastructure of red algae: mitosis outside the Ceramiales and ultrastructure of vegetative cells and tetrasporocysts of Corallinaceae. On the other hand, the discovery of proplastids in Holmsella makes it less fungus-like. However, no decisive argument has yet been produced for or against the theory. Further light should be expected from protein and nucleic acid sequences. Promising partial sequences of cytochrome c have indeed been published for red algae but the published 5 S ribosomal RNA sequences have not proven relevant to the problem. Sequences of the slower-evolving large rRNA and cytochrome c of red algae could provide convincing evidence and are urgently needed.