Pub Date : 1965-05-01DOI: 10.3181/00379727-119-30100
B EDGREN, D B ZILVERSMIT
Summary Liver slices from post absorptive dogs and fed rats were incubated for up to 3 hours with chylomicrons containing C14-palmitate and P32-phospholipid suspended in phosphate buffer. The ratio of P32/C14 in the liver slices was in most instances higher than that of the substrate chylomicrons. Re-incubation of the dog liver slices with buffer or nonlabeled chylomicrons showed some release of C14 and P32. Cyanide failed to inhibit lipid uptake by dog liver tissue, but lowered temperatures reduced the uptake. Dog liver slices deactivated by heating took up chylomicron P32 but the C14 uptake was greatly diminished from normal. Separation of chylomicrons into different size classes by centrifugation in sucrose gradients showed that the smaller particles are relatively richer in P32 than the larger chylomicrons. Evidence indicates, however, that the high P32/C14 ratios in the liver slice are probably not caused by preferential uptake of small chylomicron particles. The perfused rat liver took up the two labels in nearly the same proportion as present in the circulating chylomicrons. Apparently chylomicrons were taken up as intact particles including their phospholipid envelope. It is suggested that adsorption of chylomicron lipid on the liver slice may account for much of the “uptake” and throws some doubt on the validity of experiments with tissue slices for the study of chylomicron transport into the liver.
{"title":"UPTAKE OF C-14-1-PALMITIC ACID-P-32-PHOSPHOLIPID LABELED CHYLOMICRONS BY PERFUSED LIVER AND LIVER SLICES.","authors":"B EDGREN, D B ZILVERSMIT","doi":"10.3181/00379727-119-30100","DOIUrl":"https://doi.org/10.3181/00379727-119-30100","url":null,"abstract":"Summary Liver slices from post absorptive dogs and fed rats were incubated for up to 3 hours with chylomicrons containing C14-palmitate and P32-phospholipid suspended in phosphate buffer. The ratio of P32/C14 in the liver slices was in most instances higher than that of the substrate chylomicrons. Re-incubation of the dog liver slices with buffer or nonlabeled chylomicrons showed some release of C14 and P32. Cyanide failed to inhibit lipid uptake by dog liver tissue, but lowered temperatures reduced the uptake. Dog liver slices deactivated by heating took up chylomicron P32 but the C14 uptake was greatly diminished from normal. Separation of chylomicrons into different size classes by centrifugation in sucrose gradients showed that the smaller particles are relatively richer in P32 than the larger chylomicrons. Evidence indicates, however, that the high P32/C14 ratios in the liver slice are probably not caused by preferential uptake of small chylomicron particles. The perfused rat liver took up the two labels in nearly the same proportion as present in the circulating chylomicrons. Apparently chylomicrons were taken up as intact particles including their phospholipid envelope. It is suggested that adsorption of chylomicron lipid on the liver slice may account for much of the “uptake” and throws some doubt on the validity of experiments with tissue slices for the study of chylomicron transport into the liver.","PeriodicalId":20675,"journal":{"name":"Proceedings of the Society for Experimental Biology and Medicine","volume":" ","pages":"64-71"},"PeriodicalIF":0.0,"publicationDate":"1965-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3181/00379727-119-30100","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40796578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1965-05-01DOI: 10.3181/00379727-119-30129
C E HENDRICH, C W TURNER
Summary The mean daily feed consumption of a group of 18 female Sprague-Dawley Rolfsmeyer rats weighing a mean of 215 g during a 10-day period was 6.40 g/100 g bw. The rats were then injected subcutaneously daily with 400 μg/100 g bw of methimazole to block iodine uptake. After 10 days mean daily feed consumption was reduced to 5.97 g/100 g bw, a reduction of 6.72%, after 20 days to 5.72 g, a reduction of 10.63%, and after 30 days to 5.98 g, a reduction of 6.56%. The reductions in feed were statistically significant at P = 0.005 at each time interval. The I131 uptake was reduced from 28.08% to 1.36% after 24 days of treatment. Mean thyroid weight increased from 10.96 ± .81 mg to 21.78 ± .91 mg, an increase of 98.72% during the 30-day period, then decreased to 16.73 mg during a 7-day withdrawal period. Since reduction of feed intake to the extent observed has been shown to have no significant effect on TSR determination, it was concluded that methimazole could be used safely in estimation of TSR.
{"title":"EFFECT OF 1-METHYL-2-MERCAPTOMIDAZOLE (METHIMAZOLE-TAPAZOLE) ON FEED CONSUMPTION IN THE RAT.","authors":"C E HENDRICH, C W TURNER","doi":"10.3181/00379727-119-30129","DOIUrl":"https://doi.org/10.3181/00379727-119-30129","url":null,"abstract":"Summary The mean daily feed consumption of a group of 18 female Sprague-Dawley Rolfsmeyer rats weighing a mean of 215 g during a 10-day period was 6.40 g/100 g bw. The rats were then injected subcutaneously daily with 400 μg/100 g bw of methimazole to block iodine uptake. After 10 days mean daily feed consumption was reduced to 5.97 g/100 g bw, a reduction of 6.72%, after 20 days to 5.72 g, a reduction of 10.63%, and after 30 days to 5.98 g, a reduction of 6.56%. The reductions in feed were statistically significant at P = 0.005 at each time interval. The I131 uptake was reduced from 28.08% to 1.36% after 24 days of treatment. Mean thyroid weight increased from 10.96 ± .81 mg to 21.78 ± .91 mg, an increase of 98.72% during the 30-day period, then decreased to 16.73 mg during a 7-day withdrawal period. Since reduction of feed intake to the extent observed has been shown to have no significant effect on TSR determination, it was concluded that methimazole could be used safely in estimation of TSR.","PeriodicalId":20675,"journal":{"name":"Proceedings of the Society for Experimental Biology and Medicine","volume":" ","pages":"174-6"},"PeriodicalIF":0.0,"publicationDate":"1965-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3181/00379727-119-30129","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40796812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1965-05-01DOI: 10.3181/00379727-119-30130
J M HSU
Summary Pyridoxine deficiency in rats resulted in a decreased Zn content in the plasma, liver, pancreas, and heart tissues and an increase of Zn-65 uptake in the plasma and liver after an intramuscular injection of radiozinc. A highly significant increase in Zn-65 radioactivity was also observed in the gastrointestinal tract and feces of pyridoxine-deficient rats. This phenomenon appeared to be specific for pyridoxine since deficiency of thiamine or riboflavin did not affect hepatic Zn concentrations.
{"title":"ZINC CONTENT IN TISSUES OF PYRIDOXINE DEFICIENT RATS.","authors":"J M HSU","doi":"10.3181/00379727-119-30130","DOIUrl":"https://doi.org/10.3181/00379727-119-30130","url":null,"abstract":"Summary Pyridoxine deficiency in rats resulted in a decreased Zn content in the plasma, liver, pancreas, and heart tissues and an increase of Zn-65 uptake in the plasma and liver after an intramuscular injection of radiozinc. A highly significant increase in Zn-65 radioactivity was also observed in the gastrointestinal tract and feces of pyridoxine-deficient rats. This phenomenon appeared to be specific for pyridoxine since deficiency of thiamine or riboflavin did not affect hepatic Zn concentrations.","PeriodicalId":20675,"journal":{"name":"Proceedings of the Society for Experimental Biology and Medicine","volume":" ","pages":"177-80"},"PeriodicalIF":0.0,"publicationDate":"1965-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3181/00379727-119-30130","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40796813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1965-05-01DOI: 10.3181/00379727-119-30136
C W HIATT, D E MOORE
Summary When suspensions of rhesus monkey kidney cells (LLCMK2) are inoculated with proflavine-photosensitized poliovirus, type 1, incubated 20 minutes at 36°C in the dark, and then irradiated with bright visible light, all detectable virus in the suspension is destroyed, but 0.01 to 0.1% of the cells are capable of developing into infective centers. This finding suggests that RNA from proflavine-photosensitized poliovirus loses its photosensitivity in the early stages of cellular infection, or, alternatively, becomes stabilized shortly after penetration of the cell.
{"title":"VIRUS-FREE INFECTIVE CENTERS PRODUCED BY PHOTODYNAMIC INACTIVATION OF POLIOVIRUS IN RHESUS KIDNEY CELL SUSPENSIONS.","authors":"C W HIATT, D E MOORE","doi":"10.3181/00379727-119-30136","DOIUrl":"https://doi.org/10.3181/00379727-119-30136","url":null,"abstract":"Summary When suspensions of rhesus monkey kidney cells (LLCMK2) are inoculated with proflavine-photosensitized poliovirus, type 1, incubated 20 minutes at 36°C in the dark, and then irradiated with bright visible light, all detectable virus in the suspension is destroyed, but 0.01 to 0.1% of the cells are capable of developing into infective centers. This finding suggests that RNA from proflavine-photosensitized poliovirus loses its photosensitivity in the early stages of cellular infection, or, alternatively, becomes stabilized shortly after penetration of the cell.","PeriodicalId":20675,"journal":{"name":"Proceedings of the Society for Experimental Biology and Medicine","volume":" ","pages":"203-5"},"PeriodicalIF":0.0,"publicationDate":"1965-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3181/00379727-119-30136","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40796819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1965-05-01DOI: 10.3181/00379727-119-30102
F A KAPRAL, A M KEOGH, J H TAUBLER
Summary When S. aureus 18Z grown within dialysis sacs was implanted in the peritoneal cavity of mice, alpha toxin was produced only during periods of multiplication. The amount of toxin produced per coccus increased markedly during the first 3 generations, was maximal by the fifth, and remained constant thereafter.
{"title":"THE NATURE OF ALPHA TOXIN PRODUCTION BY STAPHYLOCOCCUS AUREUS GROWN IN VIVO.","authors":"F A KAPRAL, A M KEOGH, J H TAUBLER","doi":"10.3181/00379727-119-30102","DOIUrl":"https://doi.org/10.3181/00379727-119-30102","url":null,"abstract":"Summary When S. aureus 18Z grown within dialysis sacs was implanted in the peritoneal cavity of mice, alpha toxin was produced only during periods of multiplication. The amount of toxin produced per coccus increased markedly during the first 3 generations, was maximal by the fifth, and remained constant thereafter.","PeriodicalId":20675,"journal":{"name":"Proceedings of the Society for Experimental Biology and Medicine","volume":" ","pages":"74-7"},"PeriodicalIF":0.0,"publicationDate":"1965-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3181/00379727-119-30102","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40798137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1965-05-01DOI: 10.3181/00379727-119-30152
B M ALTURA, S G HERSHEY, B W ZWEIFACH
Summary PLV-2, a synthetic analogue of vasopressin, applied topically to the micro-vessels in the rat mesoappendix produces a graded dose response reduction in true capillary blood flow. The various vessel types contract from the venular to the arteriolar loops; the opposite of their normal profile of reactivity. This polypeptide, when injected i.v. in a single dose potentiates constrictor responses to topically applied catecholamines. In contrast to these microcirculatory effects, PLV-2 inhibits norepinephrine-induced contractions in the isolated rabbit aortic strip.
{"title":"EFFECTS OF A SYNTHETIC ANALOGUE OF VASOPRESSIN ON VASCULAR SMOOTH MUSCLE.","authors":"B M ALTURA, S G HERSHEY, B W ZWEIFACH","doi":"10.3181/00379727-119-30152","DOIUrl":"https://doi.org/10.3181/00379727-119-30152","url":null,"abstract":"Summary PLV-2, a synthetic analogue of vasopressin, applied topically to the micro-vessels in the rat mesoappendix produces a graded dose response reduction in true capillary blood flow. The various vessel types contract from the venular to the arteriolar loops; the opposite of their normal profile of reactivity. This polypeptide, when injected i.v. in a single dose potentiates constrictor responses to topically applied catecholamines. In contrast to these microcirculatory effects, PLV-2 inhibits norepinephrine-induced contractions in the isolated rabbit aortic strip.","PeriodicalId":20675,"journal":{"name":"Proceedings of the Society for Experimental Biology and Medicine","volume":" ","pages":"258-61"},"PeriodicalIF":0.0,"publicationDate":"1965-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3181/00379727-119-30152","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40796556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1965-05-01DOI: 10.3181/00379727-119-30092
J F TREON, L E GONGWER, W H RUEGGEBERG
Summary Isosorbide has been shown to be an effective diuretic when given orally to rats. The urinary output is related to dosage with an 8- or 9-fold increase for the period of 4 hours following a dose of 10 g/kg of body weight. Based on carbon-14 studies, more than 95% of the administered dose is readily excreted largely unchanged in the urine. Because of its effectiveness and very low order of acute and sub-acute toxicity, isosorbide is considered as an orally effective osmotic diuretic.
{"title":"ISOSORBIDE, A NEW ORAL OSMOTIC DIURETIC.","authors":"J F TREON, L E GONGWER, W H RUEGGEBERG","doi":"10.3181/00379727-119-30092","DOIUrl":"https://doi.org/10.3181/00379727-119-30092","url":null,"abstract":"Summary Isosorbide has been shown to be an effective diuretic when given orally to rats. The urinary output is related to dosage with an 8- or 9-fold increase for the period of 4 hours following a dose of 10 g/kg of body weight. Based on carbon-14 studies, more than 95% of the administered dose is readily excreted largely unchanged in the urine. Because of its effectiveness and very low order of acute and sub-acute toxicity, isosorbide is considered as an orally effective osmotic diuretic.","PeriodicalId":20675,"journal":{"name":"Proceedings of the Society for Experimental Biology and Medicine","volume":" ","pages":"39-42"},"PeriodicalIF":0.0,"publicationDate":"1965-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3181/00379727-119-30092","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40796569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1965-05-01DOI: 10.3181/00379727-119-30095
E A BROSBE, P T SUGIHARA, J M ADAMS
Summary Reversal of the tuberculin reaction occurred in 70% of animals treated with INH following development of a positive test. One year of INH treatment failed to sterilize the tissues in 15% of the animals. Evidence is presented that INH completely protected guinea pigs from tuberculosis when treatment was initiated prior to inoculation of a minimal dose. All non-treated controls developed visceral tuberculosis.
{"title":"PREVENTION OF TUBERCULOSIS AND REVERSAL OF TUBERCULIN REACTION IN GUINEA PIGS.","authors":"E A BROSBE, P T SUGIHARA, J M ADAMS","doi":"10.3181/00379727-119-30095","DOIUrl":"https://doi.org/10.3181/00379727-119-30095","url":null,"abstract":"Summary Reversal of the tuberculin reaction occurred in 70% of animals treated with INH following development of a positive test. One year of INH treatment failed to sterilize the tissues in 15% of the animals. Evidence is presented that INH completely protected guinea pigs from tuberculosis when treatment was initiated prior to inoculation of a minimal dose. All non-treated controls developed visceral tuberculosis.","PeriodicalId":20675,"journal":{"name":"Proceedings of the Society for Experimental Biology and Medicine","volume":" ","pages":"46-9"},"PeriodicalIF":0.0,"publicationDate":"1965-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3181/00379727-119-30095","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40796572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1965-05-01DOI: 10.3181/00379727-119-30096
J MORA, L F BOJALIL
Summary Growth of Mycobacterium acapulcensis is inhibited by D-cycloserine. This effect is completely reversed by equimolecular concentrations of D-alanine. L-alanine is totally inactive while DL-alanine is only effective at higher concentrations. L-alanine antagonized the protection afforded by D-alanine, a fact that cannot be explained by a simple competition between these diastereoisomers at the cell membrane level. In the presence of D-cycloserine a mucopeptide accumulates in the sensitive strain and also in the resistant mutant when allowed to grow at high antibiotic concentrations.
{"title":"ANTAGONISM OF THE D-ALANINE REVERSAL OF D-CYCLOSERINE ACTION BY L-ALANINE IN MYCOBACTERIUM ACAPULCENSIS.","authors":"J MORA, L F BOJALIL","doi":"10.3181/00379727-119-30096","DOIUrl":"https://doi.org/10.3181/00379727-119-30096","url":null,"abstract":"Summary Growth of Mycobacterium acapulcensis is inhibited by D-cycloserine. This effect is completely reversed by equimolecular concentrations of D-alanine. L-alanine is totally inactive while DL-alanine is only effective at higher concentrations. L-alanine antagonized the protection afforded by D-alanine, a fact that cannot be explained by a simple competition between these diastereoisomers at the cell membrane level. In the presence of D-cycloserine a mucopeptide accumulates in the sensitive strain and also in the resistant mutant when allowed to grow at high antibiotic concentrations.","PeriodicalId":20675,"journal":{"name":"Proceedings of the Society for Experimental Biology and Medicine","volume":" ","pages":"49-52"},"PeriodicalIF":0.0,"publicationDate":"1965-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3181/00379727-119-30096","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40796573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1965-05-01DOI: 10.3181/00379727-119-30133
T ASANO
Summary 1. The potential difference across the wall of the middle section of the small intestine was determined with rats, golden hamsters, and guinea pigs in vitro. The value obtained when normal Ringer's fluid was applied to the mucosal side was 8.7 ± 1.4 mv for the rat, 6.7 ± 1.2 mv for the golden hamster, and 5.9 ± 1.0 mv for the guinea pig, the serosal side being positive. 2. The potential difference was affected by sugars applied on the mucosal side. With rats and hamsters, the PD was enhanced by glucose, galactose, and 3-0-methyl glucose but not by fructose or sorbitol. 3. The potential difference was supported by glucose and galactose in the guinea pig intestine. Fructose gave a transitory enhancement in the potential difference, but 3-0-methyl glucose and sorbitol had no effect.
{"title":"EFFECTS OF SUGARS ON POTENTIAL DIFFERENCE ACROSS WALL OF SMALL INTESTINE OF RODENTS.","authors":"T ASANO","doi":"10.3181/00379727-119-30133","DOIUrl":"https://doi.org/10.3181/00379727-119-30133","url":null,"abstract":"Summary 1. The potential difference across the wall of the middle section of the small intestine was determined with rats, golden hamsters, and guinea pigs in vitro. The value obtained when normal Ringer's fluid was applied to the mucosal side was 8.7 ± 1.4 mv for the rat, 6.7 ± 1.2 mv for the golden hamster, and 5.9 ± 1.0 mv for the guinea pig, the serosal side being positive. 2. The potential difference was affected by sugars applied on the mucosal side. With rats and hamsters, the PD was enhanced by glucose, galactose, and 3-0-methyl glucose but not by fructose or sorbitol. 3. The potential difference was supported by glucose and galactose in the guinea pig intestine. Fructose gave a transitory enhancement in the potential difference, but 3-0-methyl glucose and sorbitol had no effect.","PeriodicalId":20675,"journal":{"name":"Proceedings of the Society for Experimental Biology and Medicine","volume":" ","pages":"189-92"},"PeriodicalIF":0.0,"publicationDate":"1965-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3181/00379727-119-30133","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40796816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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