Mechanism of Anti-stress Activity of Mikania cordata Root Extract in Albino Mice.

Effects of Mikania cordata root extract were investigated on stress-induced alterations in central neurotransmitters, viz., adrenaline (Ad), noradrenaline (NA), dopamine (DA) and 5-hydroxytryptamine (5-HT), and enzymatic activities of monoamine oxidase (MAO) in brain and succinic dehydrogenase (SDH) in brain and liver of mice. Both 5 h swimming and 24 h immobilization stress elicited a decrease in the levels of Ad and NA whereas they increased those of DA and 5-HT. Pretreatment with M. cordata root extract for 15 days prevented the decrement in Ad and NA and increment in 5-HT while the level of DA was further increased. There was a marked inhibition in brain MAO and stimulation in brain and liver SDH activities following both types of stress. The extract restored MAO activity towards normalization whereas it facilitated stress-induced changes in SDH activities. These dose-dependent biochemical responses may be the possible mechanism of anti-stress activity of this plant extract. [ABSTRACT FROM AUTHOR]