| central nervous system effects
Shengma (Cimicifuga species ) binds to serotonin (5HT1A) receptors (Liao et al. 1995) in vitro, and displays serotonin-blocking activities in animal studies (Yoo et al. 1995). A recent survey of 911 peri-, pre- and post-menopausal women with psychovegetative disorders reported synergistic effects for the combination of C. racemosa and Hypericum perforatum (St. John's Wort) in the management of psychological symptoms (Liske et al. 1997). Shengma species, C. dahurica rhizome tincture, and cimifugin have been reported to have sedative effects (Chang & But 1986).
CIRCULATORY EFFECTS
Actein is hypotensive in cats and rabbits, but not consistently in dogs (Newall et al. 1996; Duke 1985). Newall et al. (1996) cited a study showing that actein causes peripheral vasodilation and an increase in peripheral blood flow following administration in patients diagnosed with peripheral arterial disease; their blood pressure (normal or hypertensive) was unchanged by this treatment(1996).
OBSTETRIC EFFECTS
Early studies from the 20's showed that Cimicifuga stimulated the non-pregnant uterus of the guinea-pig and cat but depressed the pregnant uterus. The resinous cimicifugin had no effect on isolated intestine or uterus of animals (Brinker 1996). Shengma species inhibit smooth muscle contraction of isolated intestinal tissue strips and pregnant uterine tissue, but failed to stimulate non-pregnant uterus and urinary bladder tissue strips.
Although extensively used by the Eclectic medical doctors of North America for specific conditions of pregnancy, labor and post-partum (Brinker 1996), there are no recent studies clarifying the pharmacological effects of Cimicifuga during pregnancy and labor. Cimicifuga racemosa has a documented uterine stimulant effect and can induce labor according to a NAPRALERT summary (1997).
OTHER EFFECTS
Black cohosh extracts are mostly without antibacterial, antifungal, or antiviral activity although Staph. aureus is an exception according to NAPRALERT (1997). For Shangma species, antimicrobial activity was found only in vitro (Chang & But 1986). Weak cytotoxic activity against cultured HeLa cells was reported (NAPRALERT, 1997). Extracts of other species of Cimicufuga (Shengma species) may have antiinflammatory activity (Hirabayashi et al. 1995, Sakurai & Nagai 1996). Ferulic and isoferulic acid were believed to be at least partly responsible for these anti-inflammatory effects. Anti-inflammatory action against agar or dextran-induced paw edema in rats has been demonstrated for ferulic acid, C. dahurica and C. simplex when administered by intra-gastric route (Chang & But 1986). Analgesic, hypothermic and antipyretic effects have also been documented for Asian species (Sakuri & Nagai 1996, Chang & But 1986). Other noted pharmacological actions are reported for Cimicifuga species known as shengma, as discussed in Chang and But (1986). Experimentally induced convulsions in mice were reportedly suppressed by an alcoholic extract of C. dahurica.
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