Cellularity and composition of epididymal adipose tissue from cold-acclimatized rats

Summary Cold acclimatization induces morphological and compositional modifications of rat epididymal adipose tissue: a decrease in fat cell size, an increase of fat cell number per g of tissue, but no significant increase in total fat cell number in the tissue; finally, an increase in protein content and a decrease in triglyceride content.Acknowledgments. We especially thank Mr M. Joliff for his very valuable help for fat cell size determination (Hospital Bichat, Paris).     

Does an excess in liver proline increase the accumulation of collagen induced by carbon tetrachloride?

A 20-fold, diet-induced increase in liver proline does not result in an increased accumulation of hydroxyproline following chronic carbon tetrachloride administration.     

Effects of propafenone on TEA-induced action potentials in vascular smooth muscle of canine coronary arteries

Summary The Ca⁺⁺-dependent, TEA-induced action potential is blocked by propafenone in a dose-dependent manner. Such results suggests that in coronary arterial smooth muscle one mechanism of action of propafenone is to inhibit Ca⁺⁺ inward current.This research was supported by a grant from the Tennessee Affiliate of the American Heart Association and VA grant No. 1A (74)111-430100). The authors wish to thank Dr Gerhard Pfennigsdorf for supplying us with propafenone. We also wish to thank Ms Penny Williams for her technical assistance.     

Antiviral activity of glycyrrhizic acid

Summary Glycyrrhizic acid inhibits the growth of several DNA and RNA viruses in cell cultures and inactivates Herpes simplex 1 virus irreversibly.This work has been supported by a grant of Consiglio Nazionale delle Ricerche (progetto finalizzato Virus) Rome.     

Effect of cyproheptadine on the octopamine-induced responses in the mammalian central nervous system

Summary Extracellular recordings have been made from rat thalamic neurones anaesthetized with urethane, 1.5–2 g/kg i.p. Iontophoretically applied octopamine excited certain thalamic neurones in the ventral basal complex while inhibiting others. Both effects were reversibly antagonized by iontophoretically applied cyproheptadine without affecting responses to noradrenaline and dopamine.Acknowledgment. We are grateful to Merck, Sharp and Dohme for a gift of cyproheptadine HCl.     

A cytogenetic study of a barbary sheep (Ammotragus lervia) x domestic goat (Capra hircus) hybrid

Summary An account is given of stillborn male twins born to a female Saanen goat (Capra hircus) and a Barbary ram (Ammotragus lervia). The cytogenetics of the cultured hybrid cells are described and attention is drawn to the high proportion of cells which lacked one chromosome.Acknowledgment. I. gratefully acknowledge the help of Mr G.E. Embleton who took the skin biopsy of the Barbary ram.     

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.     

Collagen treated with (+)-catechin becomes resistant to the action of mammalian collagenase

Summary Treatment of radioactively labeled guinea-pig skin soluble collagen or calf skin collagen with the flavonoid (+)-catechin makes the collagen resistant to the action of mammalian collagenase but not to the action of bacterial collagenase. Complete resistance to the action of the mammalian enzyme may be achieved by incubating 0.6 mg of collagen (dry weight) with 0.1 mM (+)-catechin, followed by dialysis to remove the unbound flavonoid. Since incubation of the mammalian enzyme with (+)-catechin does not inhibit its activity, it is postulated that (+)-catechin binds tightly to collagen and modifies its structure sufficiently to make it resistant to enzyme degradation.Acknowledgments. This work was supported by grants from the Easter Seal Research Foundation of the National Easter Seal Society for Crippled Children and Adults (R-7821), and the National Institutes of Health (HL-20447). (+)-Catechin was a generous gift from Zyma SA, CH-1260 Nyon, Switzerland.     

Synthesis and properties of benzo [d,e]estra-1,3,5(10)-triene-3,17β-diol 17-acetate

Summary A new pentacyclic analogue of estradiol, benzo[d, e]estradiol 17-acetate, has been prepared and investigated for its hormonal and antitumor activity. Unlike related testosterone derivatives, the new compound did not display any interesting property.     

Activity of orotate metabolizing enzyme complex and various urea-cycle enzymes in mutant mice with ornithine transcarbamylase deficiency

Summary The overall activity of the enzyme complex consisting of orotate phosphoribosyl transferase and orotidine monophosphate decarboxylase, and of various enzymes of the urea cycle, has been studied in sparse-fur (spf) mutant mice with ornithine transcarbamylase deficiency. The enzyme complex has a lower overall activity, which could be caused by disturbed pyrimidine metabolism due to hyperammonemia. Other enzymes of the urea cycle do not show any significant change.Acknowledgments. The research was supported by a grant from the Conseil des Clubs Sociaux and Fondation Justine Lacoste Beaubien, Montréal. The authors wish to thank Ms Louise Poulin and Ms Francine Poisson for technical assistance.