Abstract

In modern world, the recognition, understanding and treatment with phytomedicines have been increased during the last few decades. However, in spite of the progress in the field of research, the mechanism of therapeutic action of most of the phytomedicine remains unknown. Because of special interest with reference to our previous work, further in depth study was carried out onSolanum nigrum leaves and fruit (red and black varieties). The crude extracts of S. nigrum(black fruit has highest activity) was selected along with ethyl acetate, chloroform, n-butanol and aqueous fraction of both varieties leaves and seeds. The effect was observed with acetylcholine, atropine adrenaline and histamine in 1×10^-2, 1×10^-4 and 1×10^-6 molar concentrations. Remarkable observed results showed the involvement of muscarinic receptors to produce the therapeutic effects and it could be assumed that the present finding support the effect like acetylcholine through muscarinic receptors in S. nigrum. Acetylcholine is the neurotransmitter present at neurotransmitter junction, brain and gastrointestinal tract etc., therefore, the drugs having acetylcholine like effects have vital role in many diseases as the parasympathomimetic drugs, thus the discovery of new drugs with minimum side effects provides a great benefit to mankind.

Key words: Solanum nigrum, muscarinic receptor, acetylcholine, smooth muscles.