Male mouse submaxillary gland secretes highly toxic proteins

Summary Submaxillary gland saliva induced by phenylephrine from male mice was highly toxic to guinea-pigs, rats and hamsters, whereas the toxicity was relatively low to mice. One of the toxic components in the saliva was isolated as a kallikrein-like enzyme.     

Natural hybridization inDrosophila

Summary Although at least 159 cases of interspecific hybridization between closely related species ofDrosophila have been obtained under laboratory conditions, only 7 cases of natural interspecific hybridization have been recorded. We report yet another case, concerningD. malerkotliana andD. bipectinata.Thanks are due to the University Grants Commission for supporting the research project of J.P.G. and to the Head of the Department for laboratory facilities.     

Induction of mouse hepatic ornithine decarboxylase by skin application of 12-0-tetradecanoylphorbol-13-acetate

Summary Topically applied 12-0-tetradecanoylphorbol-13-acetate on mouse skin was able to induce liver ornithine decarboxylase. Maximum induction occurred 10 h after a single application. Whereas no induction was noticeable at doses of 0.17 and 1.7 nmoles, 17 and 177 nmoles of 12-0-tetradecanoylphorbol-13-acetate caused about 30- and 57-fold increases respectively.This work was supported by NCI grants CA-09020, CA-07175 and P01-CA-22484.     

Dimethyloxarsylethanol from anaerobic decomposition of brown kelp (Ecklonia radiata): A likely precursor of arsenobetaine in marine fauna

Summary The novel arsenic compound, dimethyloxarsylethanol, has been isolated from anaerobically incubatedEcklonia radiata. It is proposed that this compound has a key position in the biosynthesis of arsenobetaine.C, H microanalyses were performed by the Australian Microanalytical Service.     

Bioavailability of norethindrone in women and rabbits after administration of norethindrone acetate through the subcutaneous route

Summary The levels of available norethindrone were found to be similar in women and rabbits after s.c. administration of crystalline and amorphous, norethindrone acetate respectively, and this study indicates that the rabbit may be used as an animal model for further investigation with this contraceptive steroid.     

Colony promoting activity and its target 'pre-CFUc' in genetically anemic mice of W/Wv genotype

Incubation of bone marrow cells with supernatant from long-term cultures of bone marrow cells increases the number of granulocyte-macrophage progenitor cells. This study reveals the presence of target cells of the colony promoting activity (CPA) in W/Wv mouse marrow. It is also shown that CPA does not stimulate erythroid colony formation in vitro.     

Retroviruses released from a human tumor xenograft in nude mice induce colony-stimulating factor (CSF) activity in human fibroblastic cells

Summary A human colony-stimulating factor (CSF)-producing tumor transplanted into athymic nude mice released retroviruses in vitro. The viruses induced CSF activity in human fibroblastic cell lines.     

Evidence for no relationship of the pineal activity with the neonatal shrinkage of Leydig cells in the rat

Summary The collective volume of Leydig cells in prenatally pinealectomized newborn rats declined as sharply as in intact newborn rats. Also, the collective volume in pups born in the dark declined in a fashion similar to that in pups born in the light. The results indicate that neither the pineal gland nor the light is responsible for the neonatal shrinkage of Leydig cells.This study was supported in part by a Grant-in Aid for Scientific Research (No. 548067) from the Ministry of Education, Science and Culture of Japan.