Evaluation of Hepatoprotective Potential of Rhododendron arboreum Sm. Stem Bark as Abhava Pratinidhi Dravya (Substitute) of Rohitaka (Tecomella undulata (Sm.) Seem.) Against Paracetamol Induced Hepatotoxicity in Experimental Rats

Background: Rohitaka (Tecomella undulata (Sm.) Seem.) has been considered as threatened and listed as rare at international level (IUCN, 2000). In Ayurveda classics, Rohitaka is described as Yakritpleehgulmodarhara (useful in liver and spleenic disorders). Rhododendron arboreum Sm. is used by folklore practitioners for treatment of Jaundice and marketed as Rohitaka in Nepal. Aim: To evaluate Rhododendron arboreum Sm. as an effective pratinidhi dravya (substitute) in abhava (absence) of Rohitaka (Tecomella undulata (Sm.) Seem.) with special reference to hepatoprotective activity in paracetamol induced hepatotoxicity in rats. Materials and Methods: In the present study, hepatoprotective effect of Choorna (powder) and Kwatha (decoction) of Rhododendron arboreum Sm. and Tecomella undulata (Sm.) Seem. (Choorna-0.54 g/kg body wt. and Kwatha- 4.32 ml/kg body wt. p. o. for 10 days along with paracetamol toxicant 3 g/kg body wt. p. o. on 6^th and 8^th day) were investigated against paracetamol induced hepatotoxicity. Silymarin (100 mg/kg body wt.) was used as standard hepatoprotective reference drug. Statistical Analysis Used: The obtained data were analyzed by ANOVA with Dunnet's multiple ‘t’ test and level of p<0.05 was considered as statistically significant. Results: Paracetamol treatment led to elevated levels of liver marker enzymes and disorientation in histological observations which were significantly reversed by treatment with Rhododendron arboreum Sm. and Tecomella undulata (Sm.) Seem. dependent on dosage forms. Conclusion: The study revealed that both the drugs have similar hepatoprotective effect and thus Rhododendron arboreum Sm. as “Abhava Pratinidhi Dravya” for Tecomella undulata (Sm.) Seem. with special reference to hepatoprotective activity is justified.