Antipyretic And Antinociceptive Properties Of Methanolic Extracts Of Harrisonia Abyssinica Oliv. And Landolphia Buchananii (Hallier F.) Stapf In Animal Models

ABSTRACT

Interest in herbal drugs is undergoing a renaissance at the present time. This is because herbal agents are regarded to be more effective and comparatively safe as opposed to conventional medications which are relatively inaccessible and arguably associated with various adverse effects. Harrisonia abyssinica and L. buchananii have been used by Ameru and Embu communities to alleviate various ailments. However, despite their wide folklore use, extensive literature research reveals limited scientific evaluation of their described effects. Thus, the current study aimed to evaluate the antipyretic and antinociceptive effects of their methanolic extracts. The plant samples were sourced from Siakago-Mbeere north sub-county, Embu County, Kenya. Experimental rats and mice were divided into four groups; normal group, a negative control group, reference group and experimental groups. The experimental groups were treated with stem bark extracts at concentration of 50mg/kg, 100mg/kg and 150mg/kg. The formalin paw licking test was used to determine the antinociceptive potential while evaluation of antipyretic activities was determined by using 20% turpentine solution as the pyrexia inducing agent. Evaluation of the antipyretic and antinociceptive activities was compared with Aspirin and Diclofenac as the reference drugs respectively. Harrisonia abyssinica extract reduced the rectal temperature by between 0.90% - 1.73% while L. buchananii extract reduced it by between 0.32% - 2.52%. Aspirin reduced the elevated rectal temperature by 1.70% - 2.32%. For antinociceptive study, the H. abyssinica extract reduced pain by 39.73% - 81.13% (in the early phase) and 15.92% - 69.84% (in the late phase) while L. buchananii extract reduced it by between 35.35% - 47.72% (in the early phase) and 20.57 - 55.17% (in the late phase). In the early phase, diclofenac reduced pain by 19.97% - 46.50% and 76.77-74.80% (in the late phase). Qualitative phytochemical screening results showed that the extracts possessed alkaloids, flavonoids, steroids, saponins, phenolics and terpernoids. Saponins, flavonoids and alkaloids have been associated with antipyretic and antinociceptive activities. The results of the study have scientifically confirmed the folklore use of the aforementioned plants in the suppression of pyrexia and pain.