The level of blood kinins, their creation and inactivation after one exposure to intense ultraviolet radiation in rabbits.

Experimental rabbits were exposed to ultraviolet radiation once for 45 minutes, and blood samples were obtained from the carotid artery in these animals 45 min and 3, 6 and 24 hours after the end of this exposure. In the group of control rabbits blood samples were obtained in the same way without previous exposure to radiation. The hairs on the back were cut closely at the skin and this skin area was exposed to ultraviolet rays from a Hanau Q 400 burner at 405--289 nm wavelengths and at an intensity of 134 000 erg/sec/cm2, using an UG 2 T Schott filtre and an absorber of long-wave radiation. Blood samples were taken under thiopental anaesthesia. In the samples the level of free kinins was determined in the blood, and the level of kininogen and the activity of kallikreins and kininases were determined in the plasma. In the irradiated animals a rise of the kinin level was observed, with a fall in the kininogen level most pronounced after 3 hours, while the activity of kallikreins was raised and that of kininases was decreased particularly after 6 hours.

Effect of long-term exposure of rabbits to ultraviolet radiation on the level, creation and inactivation of kinins in blood.

Experimental rabbits were exposed to ultraviolet radiation during 6 weeks once daily for 10 minutes (from a high-pressure. Hanau Q 400 mercury lamp with a Schott UG 2 T filtre and absorber of long-wave radiation using ultraviolet rays of 405--289 nm wavelength and 134 000 erg/sec/cm2 power, directed onto skin with cropped hair of the back). Under general anaesthesia with pentothal blood samples were obtained from the carotid artery in 4 groups of 8 rabbits in each group. The blood samples were taken from non-exposed control rabbits and from the experimental groups after 2, 4 and 6 weeks of exposure. In the samples the levels of free kinins in the blood, and kininogen, and the activity of kallikreins and kininases in the plasma were determined. In the irradiated animals a progressive rise of free kinins most pronounced after 6 weeks was observed, and other findings included: a fall of kininogen level particularly steep after 2 weeks, very small rise in the activity of kallikreins, and progressing reduction of the activity of kininase, particularly steep after 2 weeks.

Effect of ultraviolet radiation and kinins on oxygen uptake by tissue slices and on basal metabolism in rabbits.

The experiments were carried out on 85 rabbits in 15 groups of 5-8 animals in each. The different groups received: 1) ultraviolet radiation once during 45 minutes or daily during 10 minutes for 6 weeks, 2) bradykinin intravenously 10 microgram/kg, 3) kallikrein 5 B.U./kg intramuscularly during 3 weeks. The levels of kinins and kininogen, and the activity of kallikrein and kininases were determined in the blood several times during 24 hours after radiation exposure, and at intervals of two weeks during long-term exposure to radiation. In the same time periods after exposure the basal metabolism and the uptake of oxygen by slices of the kidneys, liver, heart and skin in vitro were determined. Determinations of aerobic metabolism were carried out also after bradykinin injection and at weekly intervals during kallikrein administration. It was found that: 1) after exposure to ultraviolet radiation there was a high rise in the level of kinins and a fall of kininogen, the activity of kininogenases was raised and that of kininases was decreased, while oxygen uptake was reduced moderately; 2) exogenous bradykinin and endogenous kinins reduced oxygen uptake in vivo and in vitro.

Effects of kinins, kallikrein and its inhibitor on certain indices of cell-mediated immunity and humoral immunity in rabbits.

The experiments were carried out on 54 rabbits in 9 groups of 6 animals each: group I -- controls, groups II, III, IV -- bradykinin i.v., groups V, VI, VII -- Depot-Kallikrein i.m. every other day for 3 weeks, groups VIII and IX -- Traskolan (trasylol) i.v. four times at intervals of 1 or 12 hours. The determined indices of cell-mediated and humoral immunity included: phagocytic activity of the reticuloendothelial system and peripheral blood leucocytes and their leukergic adhesiveness, haemagglutinin and haemolysin levels, serum complement titre, and the number of cells forming rosettes (RFC) or plaques (PFC) in the blood and spleen. These indices were determined 15 minutes, 3 and 24 hours after bradykinin administration, after 1, 2 and 3 weeks of kallikrein administration, and 1 or 12 hours after the last dose of Traskolan. Most determined indices showed always some fall. Only the phagocytic activity of the reticuloendothelial system was moderately increased in all groups, and in the bradykinin group leucocyte phagocytosis was increased slightly while their leukergic reaction was increased very strongly.