SOME CARDIOVASCULAR ACTIVITIES OF THE AQUEOUS LEAF EXTRACT OF CROTON ZAMBESICUS LINN (EUPHORBIACEAE) IN LABORATORY ANIMALS
- Project Research
- 1-5 Chapters
- Abstract : Available
- Table of Content: Available
- Reference Style: APA
- Recommended for : Student Researchers
- NGN 3000
Abstract
Croton zambesicus Linn (Euphorbiaceae) is a highly valued medicinal plant in Nigeria and West African sub-region. It is used by traditional medicine practitioners in the treatment of various ailments including hypertension. This study aims to determine some cardiovascular activities of the aqueous leaf extract and subfractions of Croton zambesicus in laboratory animals. The leaves of Croton zambesicus were extracted with water and subsequently subjected to column chromatography to obtain named sub-fractions A preliminary phytochemical screening of the aqueous extract and pooled column subfractions was carried out. The median lethal dose (LD50) of the aqueous extract was determined in mice and rats and the hypotensive activity was assessed in anaesthetized normotensive cats. The diuretic activity was determined in rats and the effect of the extract on uric acid concentration in fructose fed rats was also evaluated. The effect of the extract on isolated right atrium of the guinea pig and isolated perfused heart of the rabbit were determined. The smooth muscle relaxant activity was determined in isolated rabbit ileum while inhibition of angiotensin II, acetylcholine, calcium chloride and potassium chloride-induced contraction of the rat ileum were used to determine it‟s mechanism. The extract was screened for angiotensin converting enzyme inhibitory activity using bradykinin-induced contraction of rat ileum and spectrophotometry. The subfractions were screened for inhibitory effect on acetylcholine and angiotensin II-induced contraction of rat ileum and subfractions with inhibitory effect were further screened for hypotensive activity in anaesthetized normotensive cats. Preliminary phytochemical analysis of the aqueous leaf extract and subfractions revealed the presence of flavonoids, tannins, saponins, triterpenes and alkaloids. The oral median lethal dose (LD50) was greater than 5,000 mg/kg in both rats and mice. The extract (20 and 40 mg/kg i.v.) produced a significant (P<0.001) reduction in the blood pressure of anaesthetized normotensive cat. At 10 mg/kg the extract had significant (P<0.01) diuretic activity in rats vi comparable to that of hydrochlorothiazide (10 mg/kg). The extract (2.5 mg/ml) produced a significant (P<0.05) reduction in the tone and rate of contraction of isolated right atrium of the guinea pig. In addition, the extract (6.4 mg/ml) inhibited isoprenaline (10 nM)-induced contraction of the isolated rabbit heart. The aqueous extract (3.20 and 6.40 mg/ml) produced a significant (P<0.001) reduction in spontaneous contraction of the rabbit ileum. Furthermore, the extract (0.32-6.40 mg/ml) produced a significant (P<0.001) concentrationdependent inhibition of angiotensin II-induced contraction of the rat ileum with an IC50 of 0.50±0.03 mg/ml. Conversely the aqueous extract (0.32 and 0.64 mg/ml) had no significant inhibitory effect on acetylcholine and calcium chloride-induced contractions of the rat ileum. A ten times higher concentration of the extract (3.20 and 6.40 mg/ml) significantly (P<0.001) inhibited acetylcholine and calcium chloride-induced contraction with an IC50 of 2.3±0.04 and 2.7±0.10 mg/ml respectively. The extract (0.32-0.64 mg/ml) also significantly (P<0.001) inhibited potassium chloride-induced contraction with an IC50 of 0.3±0.01 mg/ml. The aqueous extract however, had no significant angiotensin converting enzyme inhibitory activity. Subfractions F11-13, F29, and F30-36 significantly (P<0.05) inhibited acetylcholine-induced contraction of the rat ileum with no significant inhibitory effect on angiotensin II-induced contraction. Furthermore, subfraction F11-13 caused a reduction in blood pressure (BP) at 0.8 mg/ml while subfractions F29 and F30-36 gave no BP reduction at the concentrations tested. Both the inhibitory effect on agonist-induced contraction and blood pressure reduction by the subfractions were lower compared with the aqueous leaf extract of Croton zambesicus. The data obtained from this study revealed that the aqueous leaf extract of Croton zambesicus has hypotensive, diuretic, negative ionotropic and chronotropic effects and smooth muscle relaxant activities mediated possibly via inhibition of both angiotensin 1 receptor and extracellular calcium influx through receptor operated and voltage-dependent calcium vii channels. The phytochemicals present in the extract are possibly responsible for these pharmacological activities which may be beneficial in the management of cardiovascular disorders such as hypertension.
Related Project Materials
ASSESSMENT OF THE UNITED NATIONS DEVELOPMENT PROGRAMME (UNDP) ASSISTANCE ON PROMOTION OF DEMOCRATIC NORM IN NIGERIA, 2003 -2015
ABSTRACT
This study evaluates United Nations Development Programme assistance for the promotion of democratic norm in Nigeria (2003 to 20...
DESIGN AND IMPLEMENTATION OF A COMPUTERIZED APTITUDE TEST ADMINISTRATION SYSTEM WITH CASE STUDY OF AKWA IBOM STATE POLYTECHNIC, IKOT OSURUA
Aim and Objectives of the Study
The aim of this research work is to deign a system that will be efficient to accept data...
EFFECT OF THE METHOD OF TEACHING OF ECONOMICS ON ACADEMICS ACHIEVEMENT OF TERTIARY INSTITUTION STUDENTS OSUN STATE AS A CASE STUDY
Background of the study
Economics is the study of production, distributio...
ASSESSING THE BENEFITS OF EARLY CHILDHOOD EDUCATION IN EMPOWERING MARGINALIZED COMMUNITIES
ABSTRACT: Assessing the benefits of early childhood education in empowerin...
IMPACT OF ADULT EDUCATION ON NATIONAL DEVELOPMENT
Abstract: The topic of this research is the impact of adult education on national development. This study aimed to explore how adult education...
THE IMPACT OF PUBLIC SECTOR ACCOUNTING IN NIGERIA FINANCIAL CONTROL SYSTEM
ABSTRACT
This research was aimed at finding out the impact of public sector accounting in Nigeria financial control system using Esan sou...
EVALUATION OF THE DEVELOPMENT AND MARKETING OF SERVICE PRODUCTS
Abstract
The evaluation and development and marketing of service products in educational sector is a very interesting to...
PHYTOCHEMICAL AND ANTIVENOM EVALUATIONS OF METHANOL LEAF EXTRACT OF CLERODENDRUM CAPITATUM (WILLD) SCHUM. AND THONN. (VERBENACEAE)
ABSTRACT
Clerodendrum capitatum (Willd) Schumach and Thonn. is a common medicinal plant found mainly in the tropical and sub-tropical reg...
AN EMPIRICAL ANALYSIS OF THE IMPACT OF MONETARY POLICY ON ECONOMIC DEVELOPMENT IN NIGERIA (1985–2011)
ABSTRACT
One can hardly find a country without monetary policy. As a matter of fact, monetary policy has gained a solid ground in the Nig...
DEVELOPMENT OF PILOT SIZE PROCESS FOR ZEOLITE Y AND ZSM-5 PRODUCTION FROM KANKARA KAOLIN
ABSTRACT
The successes recorded at the laboratory for the synthesis of zeolite Y and ZSM-5 using Kankara kaolin sourced from Katsina stat...
