PROPERTIES AND RESPONSIVENESS OF SPONTANEOUS MECHANICAL ACTIVITY OF ISOLATED ARTERIES

In isolated bovine facial arteries the spontaneous mechanical activity was investigated by measurement of the pressure or the flow resistance fluctuations. The time between two contraction peaks was about 15 sec±8 sec (s.e.). Mostly the frequency as well as the amplitude of the contractions showed great variations. Enhanced K+-concentration induced a decrease in frequency and an increase in force of the spontaneous contractions. By this means the irregular mechanical activity was often changed into a rhythmical one. Poisoning of the arteries by tetrodotoxin (8×10-7) did not influence the spontaneous mechanical activity. The relation between the autonomous rhythm of the arteries and the blood pressure waves is discussed. © 1968 Springer-Verlag.