[Transmural electrical stimulation in the reticular groove of adult cattle]

An in vitro study of the smooth muscle of the fore third of the reticular groove bottom was carried out in adult bovines, to determine the most favorable parameters for electrical transmural stimulation (ETS). The mechanical activity of the preparations was registered isometrically and the electric stimuli were applied by means of ring-shaped platinum electrodes. Results show that the response of this tissue to ETS is of a phasic and synchronic nature in accordance with the stimulus. The parameter values necessary to produce a homogeneous, quantifiable and reproducible response were the following: Supermaximum voltage 70-100 V, frequency 30 Hz, pulsing time 4 ms, stimulus time 5 s and intervals between each stimulus 4 min. The intervals among stimuli where 3 min long to establish the frequency curves of 2, 6, 10, 20 and 30 Hz.