Behavioural effects of naloxone in rats.

Naloxone in rats induces a behavioural syndrome closely resembling that induced by intraliquorally injected ACTH peptides. This effect is probably due to a displacement of the ACTH peptides from other receptors (e.g. opiate receptors).     

Naloxone reduces abdominal muscle tone in mice and rats

Summary The effect of naloxone on muscle tone was investigated in mice and rats at various times after administration. The naloxone effect was also tested in diazepam-pretreated animals. Naloxone was found to display muscle relaxant activity. This effect appeared to be additive to that of diazepam.     

Behavioural effects of naloxone in rats

Summary Naloxone in rats induces a behavioural syndrome closely resembling that induced by intraliquorally injected ACTH peptides. This effect is probably due to a displacement of the ACTH peptides from other receptors (e.g. opiate receptors).Acknowledgments. The authors are indebted to Dr M. J. Ferster of Endo Laboratories (Brussels) for the kind supply of naloxone. The excellent technical assistance of Mr Gianni Montorsi is gratefully acknowledged.     

Beneficial action of naloxone in splanchnic artery occlusion shock

Summary The effects of naloxone on mean arterial blood pressure, myocardial depressant factor (MDF) activity and survival, after splanchnic artery occlusion were studied in cats. Naloxone significantly improved survival in splanchnic artery occlusion shock and prevented the accumulation of MDF in the plasma.Supported in part by a research grant from the W. W. Smith Foundation.Acknowledgments. We gratefully acknowledge the expert technical assistance of Maureen Messenger.     

The effects of beta-endorphin on arginine-8-vasopressin and oxytocin levels in rat brain areas

Measurements were made of the effects of intracerebroventricular treatment with beta-endorphin (BE; 100 ng) on the arginine-8-vasopressin (AVP) and oxytocin contents of rat hypothalamic and limbic brain areas (hippocampus, amygdala and septum). The hormone concentrations were determined by radioimmunoassay. The administration of BE resulted in a significant reduction of the AVP level in the amygdala in a naloxone-reversible manner. Naloxone (Nal) administered subcutaneously significantly increased the AVP content in the septum. The results revealed that BE and Nal had regionally specific effects on the activity of the vasopressinergic system but not on that of the oxytocinergic system in the brain.     

The effects of beta-endorphin on arginine-8-vasopressin and oxytocin levels in rat brain areas

Summary Measurements were made of the effects of intracerebroventricular treatment with beta-endorphin (BE; 100 ng) on the arginine-8-vasopressin (AVP) and oxytocin contents of rat hypothalamic and limbic brain areas (hippocampus, amygdala and septum). The hormone concentrations were determined by radioimmunoassay. The administration of BE resulted in a significant reduction of the AVP level in the amygdala in a naloxone-reversible manner. Naloxone (Nal) administered subcutaneously significantly increased the AVP content in the septum. The results revealed that BE and Nal had regionally specific effects on the activity of the vasopressinergic system but not on that of the oxytocinergic system in the brain.     

(-)-(R)-1-O-Geranylgeranylglycerol from the brown alga Dilophus fasciola

Summary A novel ether lipid, (-)-(R)-1-O-geranylgeranylglycerol (1), has been isolated from the brown alga Dilophus fasciola and its structure proved by spectroscopic methods and chemical degradation.This work was supported by CNR, Rome, Italy.     

Effect of S-adenosyl-L-methionine on ethynylestradiol-induced impairment of bile flow in female rats

Summary Prevention by S-adenosyl-L-methionine (SAMe) of the bile flow reduction induced by ethynylestradiol (EE) is demonstrated by comparing the flow rate and the bile salt concentration of bile in EE-treated animals with that in animals given both EE and SAMe.SAMe was supplied by Bio Research Co., 20060 Liscate (Milano), Italy.     

Tritiated water (HTO) and inulin spaces in isolated skeletal and cardiac muscles: influence of contractile activity

Summary In isolated cardiac and skeletal muscle inulin space increased significantly after isometric contractions: no significant change (in myocardium) or a less pronounced increase (in skeletal preparations) was found following isotonic responses. The HTO space was uninfluenced by the contractile activity.This work war partially supported by C.N.R., Italy, through grant No. 74.00266.     

Analgesic effects of 3-carboxysalsolinol alone and in combination with morphine

Summary A biphasic dose-response pattern is generated by the isoquinoline, 3-carboxysalsolinol, in analgesia tests conducted in mice. Carbidopa pretreatment enhances this effect, as well as the morphine-induced analgesic increase by 3-carboxysalsolinol. Naloxone blockade of all of these responses suggests an interaction of the alcohol-based isoquinoline with central opiate receptors.We gratefully acknowledge the receipts of drugs from Merck and Co., West Point, Pennsylvania, and Endo Laboratories, Garden City, New York. A. M. is the recipient of a research scholarship from the Alcoholism and Drug Addiction Research Foundation, Toronto, Ontario, Canada.     

The ‘Società degli Spettroscopisti Italiani’: birth and evolution

The anniversary of the death of Pietro Tacchini (1838–1905), one of the pioneers of solar physics in Italy, is commemorared by this account of his major creation, the Società degli Spettroscopisti Italiani (1871). Established to promote cooperation among solar spectroscopists engaged in the study of the solar chromosphere, it was the first scientific Society devoted to spectroscopy and its astronomical applications. Its journal, the Memorie, collected most of the important works on solar physics by Angelo Secchi SJ (1818–1878), Tacchini himself, and many other protagonists of the newly born astrophysics. A brief history of the Society and its development draws on many previously unexploited archival sources, in order to show its role in raising astrophysics to the status of a scientific discipline, in the context of the astronomical research of that time in Italy and abroad, especially in the USA.     

Electrical resistance and spike activity in tarsal chemosensilla ofPhormia regina (Meig.)

Summary The relationship between hair electrical resistance and responsiveness to stimulation has been investigated in the tarsal chemosensilla ofPhormia regina. Results showed that the lower the hair electrical resistance, the higher is the spike-firing frequency.This study was partly supported by a grant from the Consiglio Nazionale delle Ricerche (CNR, Rome, Italy).     

Effect of L-amino-ethyl-cysteine,a sulfur analogue of L-lysine,on virus miltiplication in mammalian cell cultures

Summary L-amino-ethyl-cysteine clearly inhibits replication of Mengovirus; another RNA-virus (vesicular stomatitis virus) is completely insensitive. Protein synthesis is not impaired, but no active viral RNA-polymerase is detected.This work was partly supported by grant No. 73.01407.44 115.0107 of Consiglio Nazionale delle Ricerche, Roma, Italy. The technical collaboration of P. Meo and G. Conciatori is gratefully acknowledged.     

Age-dependent increase of thermal stability of in situ chromatin of rat liver and its reversal after hepatectomy

Summary An age-dependent increase of thermal stability of DNA in situ has been demonstrated in rat liver by means of microfluorimetry, which was reversed to a great extent in old regenerated liver.These authors are guests for collaboration at Ancona (Italy) till July, 1976. Their permanent address: Biological Research Institute of the Hungarian Academy of Sciences, Tihany, Hungary.     

Reinforcement with naloxone of N-n-propylnorapomorphine (NPA) capability for stimulating male rat copulatory behavior

Summary Naloxone at a dose of 2 mg·kg^–1, which per se did not significantly alter the copulatory pattern of sexually active adult male rats, did significantly reduce the intromission frequency as well as latency to ejaculation when administered before a low and inactive dose of N-n-propylnorapomorphine (0.5 g·kg^–1).     

Dichloropyrimidines: Specific inhibitors of virus growth

Summary Dichloropyrimidines can be considered as a new group of antiviral substances having a common spectrum of inhibitory action.This work has been supported by a grant of Consiglio Nazionale delle Ricerche, Rome (Italy).     

On the importance of thiols and disulphides and the antiviral action of dichloropyrimidines

Summary Free SH or SS groups of infected cells are not involved in the antiviral action of dichloropyrimidines.This work has been supported by a grant of the Consiglio Nazionale delle Ricerche, Roma (Italy).     

Stimulus-response function at several levels of background luminance,in the cat visual areas 17 and 18

Summary Stimulus-response curves of simple cells of the visual cortex were obtained by using 500-msec stationary stimuli. Background influence on single unit responses was studied. The contrast sensitivity of simple cells increases as a function of background luminance. The resolution power of these cortical cells for detecting differences in stimulus contrast decreases at background levels above 0.09 cd/m².This investigation was supported by a grant from the Consiglio Nazionale delle Ricerche, Rome (Italy).     

On the in vitro behaviour of mouse submaxillary gland cells. II. Metabolic differences between male and female C3H mice

Summary Submaxillary gland cells from female C3H mice were isolated, cultivated in vitro and their metabolic properties compared with those of male derived cells. From the results it can be concluded that these cells retain their metabolic differences when grown in vitro.This work was supported by grant No. CT 73.00642.04 from the Consiglio Nazionale delle Ricerche (C.N.R.), Roma, Italy.     

Correlation between the susceptibility of E. coli to phagocytosis and their ability to invade HeLa cells in vitro

Summary The susceptibility of several strains of E. coli to phagocytic killing by polymorphonuclear leucocytes and the ability of the same strains to invade HeLa cells were studied. It was found that only the strains resistant to killing by leucocytes were able to penetrate and multiply within HeLa cells.Acknowledgments. We thank Dr Bianca Pani who supplied us with HeLa cells. Supported by grant No. 75.00695.04 from the National Research Council of Italy (CNR).