Effects of adenosine-5′-triphosphate (ATP) on rat mast cells: Influence on anaphylactic and compound 48/80-induced histamine release

Anaphylactic histamine release from mast cells isolated from actively sensitized rats was inhibited by preincubation with micromolar concentrations of ATP. The inhibition was reversible under various experimental conditions and was counteracted by the presence of calcium in the incubation medium. Histamine release induced by compound 48/80 was similarly affected. Mast cells exposed to antigen under conditions when histamine release was inhibited by ATP became desensitized. The results indicate that ATP inhibits the release mechanism at a step which occurs after the binding of antigen to IgE.     

Decreased tuftsin concentrations in patients who have undergone splenectomy

Serum tuftsin concentrations were measured, using a radioimmunoassay developed in Israel, in normal subjects and in patients who had undergone splenectomy. Concentrations in those who had undergone traumatic and elective splenectomy were much lower. The tuftsin concentration in 38 patients with Hodgkin's disease who had undergone splenectomy during staging laparotomy was not significantly different from the mean concentration in other patients who had had elective splenectomy. In four patients who underwent splenectomy for non-malignant haematological disorders measurements made before and after operation showed that tuftsin concentrations fell significantly in the days after operation. The increased susceptibility to overwhelming infections of patients with Hodgkin's disease and others who have undergone splenectomy may be related to the low tuftsin concentrations. As pre-splenectomy tuftsin concentrations in patients with Hodgkin's disease were normal, the practice of performing staging laparotomy and splenectomy in patients with Hodgkin's disease should perhaps be reconsidered.     

Gingival and mucosal reactions after intensive chlorhexidine gel treatment with or without oral hygiene measures

Abstract – The aim of this study was to elucidate whether soft tissue reactions during chlorhexidine (CHX) treatment might be associated with meticulous oral hygiene measures. A commercially available 1% chlorhexidine digluconate gel (Hibitane Dental Gel) was applied in a custom tray for the mandibular arch, 10 min daily, for 14 days. A split mouth approach was used to allow evaluation of the effect of oral hygiene measures with toothbrush, toothpaste, and dental floss on one side of the arch. During the treatment period, 8 out of 12 subjects developed gingival and/or mucosal reactions appearing as white patches or ulcerations. Both the gingival reactions on the buccal marginal gingiva and the mucosal reactions near the margin of the custom tray occurred only when the gel treatment was combined with meticulous oral hygiene measures. The white patches, which could easily be detached, leaving ulcerated areas, consisted entirely of stratified squamous epithelium. The findings suggest that intensive treatment with chlorhexidine gel, in individually fitted custom trays, combined with meticulous oral hygiene measures may induce toxic effects on the surface layers of the gingiva and mucosa.     

Induction of ovulation with combined human gonadotropins and dexamethasone in women with polycystic ovarian disease

A combined treatment of human menopausal gonadotropin (hMG), human chorionic gonadotropin (hCG), and dexamethasone was administered to 27 infertile patients with polycystic ovarian disease who failed to conceive with clomiphene citrate and hMG-hCG alone. Twenty-two (81%) of the patients ovulated according to basal body temperature and progesterone values, and 20 (74%) conceived during one to four treatment cycles. Fifteen (74%) pregnancies terminated in live full-term deliveries (14 singletons and 1 set of twins), and 5 (25%) have terminated in first-trimester abortions. Only one of the treatment cycles was complicated by moderate ovarian hyperstimulation. The average hMG dose required for the induction of ovulation was significantly reduced from 25 ampules with hMG-hCG alone to 18 ampules under the combined treatment (P less than 0.01). The combination of hMG-hCG and dexamethasone is an additional, safe, and effective nonsurgical treatment for women with polycystic ovarian disease who have failed to respond to an hMG-hCG regimen alone.     

The influence of phosphatidyl serine on the release of histamine from isolated rat mast cells induced by different agents.

The influence of phosphatidyl serine (PS) on histamine release from isolated rat mast cells induced by antigen, compound 48/80, adenosine-5'-triphosphate (ATP), the ionophore A23187, and decylamine was studied. PS enhanced antigen-induced release but inhibited the release caused by compound 48/80, A23187, and decylamine. PS did not influence the release induced by ATP. The different effects of PS on the action of the various histamine releasing agents do not conform to a unifying model for the action of PS on the release process. Possible interactions between PS and the agents in the incubation medium as well as at specific reactive sites on the plasma membrane might explain some of the effects of PS. Consequently, the results cannot be used as evidence for the existence of basic differences in the release process induced by various calcium- and energy-dependent releasing agents.     

Urinary Excretion of I131-Diodrast Injected Intraventricularly in Communicating Hydrocephalus and Aqueduct Stenosis

Nine cases of expansive infantile hydro-cephalus were investigated by injecting Small amounts of I¹³¹-Diodrast intra-ventricularly. Urinary excretion of the tracer was determined during the first 4-5 hours after injection. The cumulative excretion of Diodrast from the C.S.F. differs in cases with communicating hydrocephalus from those with stenosis of the aqueduct. The investigation is rapid and easily performed and has not produced any side effects.     

On the inhibitory action of DFP and PMSF on histamine release from isolated rat mast cells

Conclusion The present results furnish an alternative explanation to the inhibition of histamine release induced by so-called esterase inhibitors. The inhibition can well be explained on the basis that these agents inhibit metabolic energy production necessary for the coupling of stimulation to secretion in the rat mast cells.The financial support of the Danish Medical Research Council (Grant No. 512-5044) and Hesselman's Foundation, Sweden, is gratefully acknowledged.