The study has been conducted on 20 Bufflo female rats aged 4–6 months, from which the uterus strips have been taken directly after slaughter. Isolated uterus strips were placed in 4 automatic water bath chambers. After recording of spontaneous contraction activity of the isolated strip, calcium channel blockers i.e. diltiazem, nifedypine, verapamil were added into the bath organ. Doses of the preparations were determined experimentally. The experiments proved that an isolated uterus strip showed spontaneous periodical contraction activity for about 8-12 hours. An average contraction frequency amounted to 1.36 ± 0.33 contractions per minute, and strength of a single contraction was on average 2.7 ± 0.7 grams. Administration of oxytocin into the incubation bath organ increases the frequency (by 44.85 ± 13.42%) and strength (by 39.5 ± 18.33%) of the spontaneous uterine contraction activity. Administration of the calcium channel blockers: diltiazem, nifedypine, verapamil into the incubation bath organ causes a decrease or atony of the frequency and strength of the uterus muscular coat contractions depending on concentration of an active substance of the preparation. Nifedypine is the strongest calcium channel blocker. Blocking of the calcium channels with a 2.8 x 10^-8 mol/l dose of nifedypine resulted in a decrease in frequency by 40 ± 9.86%, whereas a dose ten times higher (2.8 x 10^-7) caused total atony of the spontaneous uterine contraction activity. Administration of oxytocin into the incubation bath organ after the prior total blocking of the Ca²⁺ channels does not result in an increase in the isolated strip contraction activity.

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