BACKGROUND:

There are reports in the literature about the effects of peat and its products on spontaneous contractile activity (SCA) of smooth muscles. In our earlier work we showed that the aqueous peat extract is a stimulus for SCA of smooth muscle fibres. After longstanding (4-5 h) influence from aqueous peat extract, a self-blocking effect of these influences can be observed. The mechanism of action could not be determined up to now.

PURPOSE:

The purpose of this study is to elucidate the peat mechanism of action.

MATERIAL AND METHODS:

In organ baths, the effects of aqueous peat extract on the SCA from smooth muscles have been studied under normal conditions and with presence of different receptor blocking substances.

RESULTS:

Our investigations show that only with simultaneous blocking of alpha(2) and D(2) receptors the stimulating activity of aqueous peat extract on the SCA of smooth muscle fibres can be suppressed. The self-blocking actions of the stimulating activity of aqueous peat extract on the SCA of smooth muscles are interconnected with blocking of alpha(2 ) adreno and D(2) receptors.

CONCLUSION:

The aqueous peat extract contains biologically active substances, which have a partial agonistic effect on alpha(2 ) and D(2) dopamine receptors. Corresponding to the results we start out at pharmacological effects as they are known from the mentioned receptors. The clinical efficacy have to be shown by clinical trials.