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A rheographic evaluation of peripheral blood flow during isometric contraction (handgrip) has been done in 25 attendants of the Air Force Medical Service (mean age :20 years). The velocity of sphygmic wave, the sphygmic amplitude and, the peak time, heart rate and blood pressure have been measured at rest and during handgrip. The velocity of sphygmic wave does not change in all the subjects; the sphygmic amplitude is decreased of 10% (p less than .001), the peak time is decreased of 9% (p less than .001). Because sphygmic amplitude and peak time are directly proportional to flow volume, and their reduction significantly express a decrease of flow volume. The authors believe that the blood flow reduction is induced by the excitation of sympathetic peripheral alpha-receptors, not more balanced from sympathetic cholinergic vasodilator fibers. The actual result is an increase of the peripheral vascular resistances.

R-wave changes have been measured in 90 normal subjects during exercise testing on the bicycle. We have found a 22,2% R-wave mean decrease in all the subjects independently from their age. This results, in our opinion, may be due to the heart volume decrease during dynamic exercise in normal subjects. In according to the Brody effect, heart volume reduction decrease radially orientated cardiac vectors and therefore QRS amplitude is reduced.

In the present work a method is described to standardize each step of leukocyte capillary tube migration assay. The conclusions of our study are: natrium heparin can be used as anticoagulant; the use of calibrated microcapillaries is recommended; migration chambers must lay on a horizontal surface; results can be evaluated by a ocular for radial immunodiffusion from the 16th to 20th hour of migration.

In the present work we have evaluated the effect of decreasing concentrations of normal plasma in TC 199 on leukocyte capillary migration. From the 1st to the 4th hour of migration, normal plasma at 100%-80%-60%-40% concentration, significantly inhibits leukocyte migration. The inhibitory effect is lost, only by a few plasmas, at 60% and 40% concentration, during the following migration hours. Normal plasma at 20% and 10% concentration doesn't show any inhibitory effect on leukocyte capillary migration. Therefore, for clinical studies on pathological plasmas we recommend the use o plasma at 20% or 10% concentration to avoid aspecific inhibition.

We have investigated the effect of four anticoagulant drugs (Calbiochem Heparin, Liquemin Roche, EDTA and Na citrate) on polymorphonuclear granulocyte capillary migration to evaluate a possible modification induced by these drugs on migration function. We can state that any modification is induced by these drugs on granulocyte capillary migration in vitro.

The hemodynamic changes of the pulmonary vascular system in patients with aortic stenosis, has been evaluated during isometric exercise (handgrip). Heart rate, left ventricular sistolic pressure and pulmonary artery sistolic pressure, increase significantly while pulmonary vascular resistences are uneffected. In conclusion, the pulmonary response to handgrip olso in patients with aortic stenosis shows the same.

The hemodynamic changes of the pulmonary vascular system in patients with mitral stenosis, has been evaluated during isometric exercise (handgrip). Heart rate, pulmonary artery sistolic, dyastolic, mean and "wedged" pressure, end-dyastolic pulmonary vascular and trans-mitralic gradient, total pulmonary resistences increase significantly. Cardiac output and pulmonary vascular bed are probably related to the tachycardia induced by the handgrip, and to the conseguent shortening of the dyastolic left ventricular filling time.

We have measured R-wave amplitude during isometric stress-handgrip test in 30 normal subjects, without finding any significative variation. We believe, in according to our angiographic and echocardiographic experience, that such a behaviour is due to the absence of heart volume modification during handgrip test.