Cardiovascular receptor binding affinity of aqueous extracts from Allium species.

INTRODUCTION

The aims of this study were to evaluate whether the antihypertensive effect of garlic could to be associated to interactions with adrenergic and dopaminergic receptors involved in regulating blood pressure and to compare these data with those obtained from wild Allium species.

METHODS

The aqueous extracts of bulbs or leaves of Allium sativum L. (garlic), Allium neapolitanum Cyr., Allium subhirsutum L., and Allium roseum L. were tested for their in vitro affinity for the adrenergic (alpha(1), alpha(2), beta(1) and beta(2)) and dopaminergic (D(1) and D(2)) receptors by radioligand binding assays.

RESULTS

Interesting results were shown by bulbs extracts of A. neapolitanum and A. subhirsutum with higher affinities for the beta(2) receptors and by bulbs extract of A. roseum for D(2) receptors.

CONCLUSIONS

The known antihypertensive activity of Allium sativum cannot be correlated with binding to receptors involved in blood pressure regulation. However, aqueous extracts of the wild-type species of Allium show much higher affinities, warranting further explorations.