Abstract

Analgesic Potential of Acetone Leaf Extract of Caesalpinia volkensii Harms in Mice

Mworia JK, Gitahi SM, Juma KK, Njagi JM, Mwangi BM, Aliyu U, Njoroge WA, Mwonjoria KJ, Nyamai DW, Ngugi MP and Ngeranwa JJN

Pain is defined as unpleasant feeling essential for body’s defense system. It acts as a warning signal against disturbances in the body. Conventional antinociceptives are expensive and have many side effects. Continued use of these drugs may lead to tolerance and resistance. Medicinal plants have been used to relieve pain and form a better alternative. Herbal antinociceptives are affordable and have arguably fewer side effects. Caesalpinia volkensii (Harms) has pharmacological activities that include antimicrobial, immune modulatory properties and antimalarial. It is used locally by people in Embu County as analgesics. This study was designed to bioscreen the acetone leaf extracts of C. volkensii (Harms) for antinociceptive effects in mice.. The plant parts were collected from Mbeere north sub-county, Embu County, Kenya. The samples were prepared and extraction of the active compounds carried out using acetone. Swiss albino mice were divided into five groups of five mice each: Normal, negative, reference and experimental group. Pain was induced experimentally using formalin and acetic acid. The experimental groups were treated with 50 and 100 mg/kg dose ranges of the plant extract. Mice were injected intraperitoneally with doses of the herbs, diclofenac and the vehicle. Thirty minutes later the animals were injected with 0.01ml of 2.5 % formalin in the sub planter region of the left hind paw and the other set with 0.4ml of 5% acetic acid. The total time spent lifting; biting, licking the paw and writhing were counted and scored. The acetone leaves extracts tested at different dose levels lowered paw licking time in a dose dependant manner, Further, the phytochemical screening results showed that the acetone leaves extracts of C. volkensii (Harms) have phytochemicals associated with antinociceptive activities. The study has established that the acetone leaves extract of C.volkensii (Harms) is effective in management of pain.