Action and interaction of two 888-1888-1888-1agonists,methoxamine and St 587, on the rabbit's blood pressure and EEG

Summary In rabbits methoxamine reversed the vasopressor effect of St 587 and abolished the EEG synchronizing action of St 587. The interaction on the blood pressure could be ascribed either to the different chemical structures of St 587 and methoxamine or to partial agonistic properties of St 587. The interaction on the EEG appears to be more complex.     

Comparison ofβ-Adrenergic blocking activity of DCI,H56/28, ICI50172, LB46, methoxamine,MJ 1999 and propranolol in the blood perfused canine papillary muscle preparation

Zusammenfassung Nachweis, dass der-Blocker LB46 am blutperfundierten Papillarmuskel des Hundes eine grössere Aktivität aufweist als 6 andere bekannte-Blocker.     

Interrelationship between mean arterial blood pressure,blood flow,and vascular resistance in solid tumor tissue of DS-carcinosarcoma

Zusammenfassung In vivo-Untersuchungen der Tumordurchblutung an Implantationstumoren eines DS-Carcinosarkoms in der Rattenniere zeigen eine deutliche Abhängigkeit der Durchblutungsgrösse vom Tumorgewicht. Bei Variation des arteriellen Mitteldrucks zwischen 40 und 135 mm Hg steigt die Durchblutung der einzelnen Tumoren linear mit zunehmendem Perfusionsdruck an. Eine zunehmende Rarefizierung der terminalen Strombahn mit ansteigendem Tumorgewicht wird belegt durch eine starke Zunahme des Strömungswiderstandes, der schon bei sehr jungen Tumoren wesentlich höhere Werte als bei verschiedenen Organen aufweist.

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Supported by the Landesversicherungsanstalt Rheinland-Pfalz, Speyer/Rh.     

Model of the interaction between trypsin and alpha 2-macroglobulin of porcine serum]

A comparative study of the dissociation into subunits of Porcine alpha2 M, either native or bound to trypsin (Tn), has been carried out in order to determine the modifications of the alpha2 M structure due to the formation of the Tn-alpha2 M complex. Analytical ultra-centrifugation at pH 3.5 shows that the dissociation is smaller when alpha 2 M is bound to trypsin. Electrophoresis in 4% polyacrylamide gels, in presence of 0.1% SDS, of alpha2 M and Tn-alpha2 M incubated in 1% SDS leads to the same conclusion; the enzyme must stabilize the quaternay structure of alpha2 M. In presence of SDS + beta-mercaptoethanol, only a molecular weight (M.W.) 200,000 band is revealed in electrophoresis pattern of native alpha2 M. In the case of reduced Tn-alpha2 M, some other bands of M.W. 100,000, 50,000, 30,000 appear. When trypsin is inactivated by TLCK 100,000 M.W. band is present, accompanied by the 200,000 M.W. band whose intensity is function of the alpha2 M concentration. The 100,000 M.W. band appears therefore characteristic of the formation of the complex which must imply a proteolytic cleavage in the middle of the 100,000 polypeptidic chain of alpha2 M. A model of the complex is proposed in which the enzyme forms a proteic bridge between the two halves of the alpha2 M molecule.     

The effect of LSD-25 upon the cerebral blood flow and EEG in cats

Zusammenfassung Es wurde gezeigt, dass LSD-25 (d-Lysergsäure-diäthylamid) in Dosen von 30 bis 100 /kg Körpergewicht bei dernichtnarkotisierten Katze (encéphaleisolé) meistens cine Erhöhung des zerebralen Gefässwiderstandes herbeiführte. In die Carotis injiziert, gab LSD-25 in denselben Dosen nach vorübergehender, halbseitiger Aktivierung eine Depression des Elektroenzephalogrammes. Kleinere Dosen gaben im EEG eine Aktivierung oder waren ohne Wirkung.     

Action of reserpine and imipramine on intracellular storage of 5-hydroxytryptamine in blood platelets

Zusammenfassung In isolierten Blutplättchen von Katzen vermindert Imipramin im Gegensatz zu Reserpin das endogene 5-Hydroxytryptamin (5HT) und die 5HT-Speicherorganellen nicht wesentlich, obwohl es wie Reserpin die Aufnahme von exogenem 5HT herabsetzt. Hemmung des Membrantransportes von 5HT durch Imipramin scheint also das intrazellulär gespeicherte 5HT nur relativ wenig zu beeinflussen.     

Effects of injury on the concentration of alpha1-macroglobulin and alpha2-macroglobulin in the plasmas of male and remale rats.

The effects of injury on the concentration of alpha1-macroglobulin and alpha2-macroglobulin in the plasmas of male and remale rats has been investigates. At 5 days after injury to the male rats the alpha1-macroglobulin concentration increased to 131% of its preinjury value. The alpha2-macroglobulin concentration increased more rapidly to a maximum of 86 times its initial value. In the female rats alpha2-macroglobulin increased only slightly and alpha1-macroglobulin not at all.     

The effect of nicotine on blood pressure in the genetically hypertensive mouse

Summary Mice genetically selected for high and low blood pressure were exposed to nicotine via a single injected dose or addition to drinking water for 52 weeks. In the acute study, the response of mice with high blood pressure was a statistically significant increase in blood pressure. In the chronic study the pattern of response to nicotine ingestion was similar for mice with high blood pressure and those with low. Both lines responded with an increase in blood pressure after 6 weeks followed by a decrease to below baseline blood pressure at 12 weeks.This research was supported in part by an allocation from the General Research Fund of the University of Kansas.     

Modulation of C2 and C3 gene expression of human peripheral blood monocytes by interleukin 1 beta, interferon gamma, tumor necrosis factor alpha and lipopolysaccharide.

The effect of interleukin 1 beta (IL-1 beta), interferon gamma (IFN-gamma), tumor necrosis factor alpha (TNF alpha) and lipopolysaccharide (LPS) on the expression of the C2 and C3 genes in human adherent monocytes was studied. Stimulation of monocytes with IFN-gamma increased both C2 and C3 mRNA. IL-1 beta also increased C2 mRNA level, whereas C3 gene expression was not enhanced. TNF alpha failed to increase either C2 or C3 mRNA. LPS increased C2 mRNA, but suppressed C3 gene expression. These results suggest that C2 and C3 production by monocytes is regulated by IL-1 beta and IFN-gamma in the local tissues.     

Effect of sudden reductions of the arterial blood pressure on the mean diastolic coronary resistance

Summary At the beginning of a 10 sec arterial haemorrhage, vascular elasticity induces an increase of mean diastolic coronary resistance. Then, the increase is counteracted by the relaxation of the vascular musculature, which causes a coronary hyperaemia when, after the haemorrhage is arrested, the vascular wall is stretched by a sudden though slight increase of blood pressure.Acknowledgment. The authors wish to thank Mr Rodolfo Dalla Valle for his technical assistance.