Journal of Vascular Research

Henrich, H.; Singbartl, G.

doi: 10.1159/000157974pmid: N/A

Dilatory responses of the isolated intestinal vasculature of the rat have been studied during constant infusion of acetylcholine (Ach), isoproterenol (IP) andmyotropic, i.e. Ca⁺⁺ antagonistically acting doses of propranolol. The initial vasodilation was followed by a succeeding increase of flow resistance. This effect, called ‘escape phenomenon’ could constantly be proved during application of Ach, was dosedependent and reached a maximal escape quotient of nearly 30%. Large vasoconstrictive doses of Ach also showed an escape phenomenon indicating the probability of one basal mechanism causing the escape from vasodilation and vasoconstriction. Vasodilations evoked by infusion of IP and large doses of β-blockers showed escape reactions only in some cases. The discrepancy between the different escape behaviour can be understood by comparing the rate of development of the initial vasodilation, which was two times slower for IP and propranolol than for Ach. The escape from Ach-elicited vasodilations could be clearly reduced by myotropic acting doses of LB 46. These results demonstrate that the escape from vasodilation is not a drug-specific phenomenon but is of myogenic origin. The analogy of the escape from vasodilation and vasoconstriction suggests a common basal myogenic mechanism perhaps due to changes of Ca⁺⁺-fluxes. Thus, the initial vascular reaction would represent an ‘overshoot’ and the escape an adjustment reaction in a ‘steady-state system’.

Thulesius, Olav

doi: 10.1159/000157975pmid: N/A

The present study summarizes previous studies about the principle of measuring capillary filtration coefficients in animals and humans. Some observations have been presented as to the technical aspects of measurement and changes of capillary filtration due to muscular exercise, infusion of vasodilating substances and arterial occlusion. The mechanism of altered capillary filtration is discussed.

Hladovec, J.; Přerovský, I.

doi: 10.1159/000157976pmid: N/A

The conductivity of subcutaneous tissue was measured in rats with various types of experimental oedema. The measured values depended on the water content in tissues and not on the origin of oedema. The conductivity measurements of the subcutaneous tissue above the ankles were also used in patients with several types of clinical oedema in comparison with a group of normal subjects. The method is simple and well reproducible. It is suitable particularly for the evaluation of changes in oedema development.

Bartoš, J.; Pokorný, J.; Petz, R.; Vančura, J.; Volek, V.; Mildeová, E.

doi: 10.1159/000157977pmid: N/A

In experimental work on 134 dogs, the authors succeeded in verifying a non-suture end-to-end method of vessel anastomosis for the purpose of heart revascularization. Instead of usual steel tubes, the authors used fibrin tubes which make the method more suitable for clinical use also. This method seems to be more advantageous especially for operation on coronary arteries of very small peripheral diameter and possibly for the treatment of acute infarction, too. Besides, it was proved that the best way to prevent ventricular fibrillation after revascularization is the intermittent and gradual release of the blood flow through the anastomosis. The question of possible diagnosis of an unsuccessfull operation during the postoperative course was also studied. It was found that besides electrocardiographical and coronarographical examinations, the plasma-enzyme level (especially SGOT) may be of some help in solving this question.