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L Ivarsson

Publications and source records attributed to L Ivarsson.

25 records · Page 2Linked to original sources

Heparin, dextran 1000 and metastasis formation after I.V. tumour cell injection in dextran non-sensitive rats.

The present study of the effect of heparin and dextran 1000 on the metastasis formation after i.v. tumour cell injection in dextran non-sensitive rats using a syngeneic 20-methylcholanthrene induced fibrosarcoma showed that heparin treatment decreased with formation of pulmonary metastases in animals both untreated and treated with dextran 1000. Treatment with dextran 1000 increased the formation of pulmonary metastases in animals both untreated and treated with heparin and the effect of dextran 1000 was thus not affected by heparin treatment. Heparin did not have any direct action on the tumour cells, which influenced metastasis formation. The data suggest that heparin acts as an anticoagulant with decreased microthrombus formation around lodged cells and that dextrax 1000 stimulates metastasis formation primarily by mechanisms other than intravascular coagulation.

Animals↗

Plasma volume after dextran infusion in rats sensitive and non-sensitive to dextran.

Plasma volume determinations were done with RIHSA under normal conditions and after intravenous infusion of dextran solutions. The plasma volume of normal rats in millilitre was found to be 0.026 X body weight + 0.92. Infusion of dextran into dextran-sensitive Sprague-Dawley rats was followed by a marked plasma volume reduction and haemoconcentration as consequence of an anaphylactoid reaction. This reaction could be partially inhibited by pretreatment with cyproheptadine chloride. Plasma volume determination with the method used in this study can be used to evaluate the dextran-anaphylactoid reaction. In dextran non-sensitive Wistar rats, infusion of dextran had a strong plasma volume-expanding effect comparable to the plasma volume-expanding effect of dextran in humans. No signs of abnormal leakage of fluid out into the extravascular space were evident, which indicated that the Wistar rats really were non-sensitive to dextran.

Animals↗

Dextrans and the formation of pulmonary metastases after intravenous tumour cell injection in rats non-sensitive to dextran.

This study showed, that in a syngeneic tumour-host system in rats non-sensitive to dextran, dextran 40 and dextran 100 did not stimulate metastasis formation after intravenous tumour cell injection, neither when given as intravenous pretreatment nor when given in the tumour cell suspension. Dextran 1000 stimulated the formation of metastases in both these situations. Disturbed microcirculation, intravascular coagulation and effects upon the tumour cell membrane appear to be the main resons, why dextran 1000 stimulated metastasis formation under the experimental conditions used.

Animals↗

[Fibrinogen metabolism and distribution in tourniquet-trauma].

The distribution and turn-over of 131J-labelled fibrinogen was studied in traumatized rats. Tourniquet-trauma resulted in a pronounced accumulation of labelled fibrinogen in the traumatized region. The accumulation was at the expense of all nontraumatized-tissue. In controls there was a parallel decline of total-body-activity and plasmaactivity. The T.B.A. of traumatized animals showed a similar disapprearance-rate, while there was a pronounced reduction of circulating labelled fibrinogen.

Animals↗