Effect of testosterone on the kinetics of the development of suppressor cells in adjuvant arthritis

Summary The induction of unresponsiveness to mycobacterial adjuvant took a longer time in male DA rats than in female rats. A shift in the induction time of unresponsiveness in males toward the female type was brought about by castration, but could be reverted to the male type by the application of testosterone. The transfer study revealed that cells capable of preventing arthritis required a longer incubation time for their development in males than in females. This suggests that testosterone inhibits the development of suppressor cells in adjuvant arthritis.Acknowledgments. We are grateful to The Naito Foundation Research Grant for 1983.     

Peptidylarginine deiminase in rat and mouse hemopoietic cells

Summary Peptidylarginine (protein-L-arginine) deiminase activities have been demonstrated in extracts of rat and mouse peritoneal macrophages, bone marrow cells, splenic adherent cells, neutrophils, and mouse monocyte/macrophage cell lines. The enzyme in these cells is indistinguishable from the skeletal muscle enzyme with respect to immunochemical properties.     

Hypersensitivity to endotoxin hepatotoxicity in rats with inflammatory lesions

Summary The ratio of sinusoidal nonparenchymal cells to hepatocytes in rat liver was significantly increased following induction of inflammation, and decreased after subsequent exposure to endotoxin, particularly in the region around the terminal portal venules. Rats with inflammatory lesions were more sensitive to endotoxin hepatocytotoxicity than normal controls, as judged from the dose-dependent increase in activity of serum transaminases and from the extent of liver tissue injury. In addition, these animals, which were already in a state of depletion of hepatic glycogen, demonstrated marked hyperglycemia 24 h after endotoxin administration in small doses of less than 2 mg/kg.     

Integrins and cardiovascular disease

Cardiovascular diseases involve abnormal cell-cell interactions leading to the development of atherosclerotic plaque, which when ruptured causes massive platelet activation and thrombus formation. Parts of a loose thrombus may detach to form an embolus, blocking circulation at a more distant point. The integrins are a family of adhesive cell receptors interacting with adhesive proteins or with counterreceptors on other cells. There is now solid evidence that the major integrin on platelets, the fibrinogen receptor α _IIb  β ₃ , has an important role in several aspects of cardiovascular diseases and that its regulated inhibition leads to a reduction in incidence and mortality due to these disorders. The development of α _IIb  β ₃ inhibitors is an important strategy of many pharmaceutical companies which foresee a large market for the treatment of acute conditions in surgery, the symptoms of chronic conditions and, it is hoped, maybe even the successful prophylaxis of these conditions. Although all the associated problems have not been solved, the undoubted improvements in patient care resulting from the first of these treatments in the clinic have stimulated further research on the role of integrins on other vascular cells in these processes and in the search for new inhibitors. Both the development of specific inhibitors and of mice with specific integrin subunit genes ablated have contributed to a better understanding of the function of integrins in development of the cardiovascular system.     

Effect of high doses of somatostatin on adenylate cyclase activity in peripheral mononuclear leukocytes from normal subjects and from acute leukemia patients

Summary In normal lymphocytes somatostatin non-competitively inhibited basal (ID₅₀ 5×10^–4 M) and isoproterenol- and forskolin-stimulated adenylate cyclase activity (Ac). In acute leukemia blasts, non-responsive to isoproterenol, forskolin, which activates the catalytic subunit, stimulated and somatostatin inhibited Ac, thus indicating the leukemic enzyme, though defective, retains the inhibitory pathway and catalyst function.     

The effects of ethanol on embryonic actin: A possible role in teratogenesis

Summary When the neural crest is cultured in the long or short term presence of ethanol, monoclonal anti-actin reveals the development of a disorganized actin cytoskeleton. In the long term, many cells fail to differentiate morphologically, whereas in the short term already differentiated cells rapidly alter their shape and their cell-to-cell contacts.     

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.     

Gametes contain angiotensin converting enzyme (kininase II)

Summary The localization of angiotensin converting enzyme (ACE) in the gonads of the normal rabbit was studied by immunofluorescence and immunoelectron microscopy. The enzyme is present in the cytoplasm of testicular spermatids and of epididymal and ejaculated spermatozoa, and on the surface of follicular and tubal cocytes. These findings support the hypothesis that ACE has a role in gamete maturation and in fertilization.Acknowledgments. This study was supported by NIH grant AM36807 and by grants from the American Heart Association, the Joe and Emily Lowe Foundation, and the Dana Foundation. We thank L. Fernandez, B. Luders, I. Pawlowski, and K. Schwegler for technical assistance.     

Serotonin is localized in endothelial cells of coronary arteries and released during hypoxia: A possible new mechanism for hypoxia-induced vasodilatation of the rat heart

Summary In this report we demonstrate the immunocytochemical localization of serotonin in endothelial cells of rat coronary vessels and a significant increase in the release of serotonin into the perfusate of Langendorff rat heart preparations during hypoxia. It is suggested that serotonin, localized in endothelial cells, is released during hypoxia and could provide part of a pathophysiological mechanism for vasodilatation to protect the heart from damage due to hypoxia.This research was supported by the British Heart Foundation and the excellent technical assistance of Jon Bokor is gratefully acknowledged.     

Super-high sensitivity systems for detection and spectral analysis of ultraweak photon emission from biological cell cells and tissues

Summary In this paper we summarize and discuss the modern technology and systems, studied and established by our research group, for performing the detection and special analysis incorporated with the super-high senstivity photon counting method for the study of ultraweak photon emission; for example, extra-weak bioluminescence and chemiluminescence from living cells and tissues, closely related to biochemical and biophysical processes and activities. An excellent sensitivity of the basic photon counting system, making it possible to achieve count rates in the very low range of one photoelectron per second to one per minute, allowed us to carry out in vivo as well as in vitro measurements, and analyses of ultraweak bioluminescence and chemiluminescence. Recent results concerning ultraweak photon emission from blood samples and organ homogenates of rats are presented and reviewed as one of the interesting and valuable applications of our modern technology for studying ultraweak cell and tissue radiation.