Lactacidemia, catecholaminemia and blood pressure have been measured in normal rats submitted to a swimming exercise. They are overloaded (6% body weight). Lactacidemia is increased after 15 minutes swimming. Adrenalinemia and noradrenalinemia are also statisticaly increased. Blood pressure falls during the exercice period. Hypotension is prevented by beta adrenergic blockade.

Blood Pressure↗

PubMed1975

[Electroretinogram in the nocturnal Prosimian Perodicticus potto].

There is histological evidence for the presence of cones in potto's retina: about 1 cone for 300 rods. The ERG of the dark adapted animal resembles that of the night monkey. In the potto's retina some red sensitive elements respond to wavelenghts beyond those which affect visual purple. The ERG evoked by these long wavelenghts differs from that produced by white light, suggesting a duplex character of the retina. These red sensitive receptors dark adapt faster than the others. However their fusion frequency is low, if compared with that in other species with a duplex retina. Nevertheless in potto the critical fusion frequency is higher for red light than for blue light.

Animals↗

PubMed1975

[General pharmacologic properties of silybine and silymarine in the rat].

Silybine is the main active substance of the polyhydroxyphenylchromanone derivatives extracted from the seeds of Silybum Marianum. In the normal albinos rat, this pure compound (from 2 mg/100 g) lowers directly the systemic blood pressure. It does not increase vascular permeability. It potentiates post-serotonine hypertension. Silybine antagonizes cutaneous oedemas and suppresses the fall of blood pressure induced by dextran polymers. It inhibits anaphylactic shock in rats sensitized by ovalbumine. Silybine seems to be a stabilizer of mastcells membranes, thus preventing histamine release.

Anaphylaxis↗

PubMed1975

A common idiotype on human macroglobulins with anti-I and anti-i specificity.

The reactions of an idiotypic antiserum prepared against an anti-I cold agglutinin (Da) were studied in radioimmunoassays which were designed to detect partial rather than complete idiotypic cross-reactions among cold agglutinins with anti-I and anti-i activity. Proteins showing strong idiotypic cross-reactions by gel precipitation could not inhibit the binding of 125I-labelled Da to anti-Da (individual specificity). It was necessary to use 125I-labelled cross-reactive proteins in order to demonstrate cross-idiotypic specificity and even the choice of the reference cross-reactive protein was important. The use of the 125I-labelled Fab fragment of a cross-reactive anti-I cold agglutinin (Low) allowed the detection of an idiotypic determinant common to at least 73% of cold agglutinins with specificity for the I-i antigen complex. Among these were two transiently occurring cold agglutinins following M. pneumoniae infection and infectious mononucleosis. This idiotypic determinant was not detected on cold agglutinins with anti-Pr specificity or on isolated monoclonal IgM or IgG lacking cold agglutinin activity, but it was present in low concentrations in pooled IgG. The common idiotypic determinant was found on IgM kappa cold agglutinins belonging to different VK subgroups and on an IgM lambda protein. A knowledge of the structural basis of such idiotypic cross-reactions among proteins from unrelated individuals should provide important information about the genes controlling the synthesis of site-related regions of antibodies.

Agglutinins↗

PubMed1974