Antihypertensive and electrolyte modulatory effect of ethanol extract of Terminalia catappa leaf following L-NAME induced hypertension in male Wistar rats

Background; Hypertension is the major leading risk factor for atherosclerosis and other diseases, especially renal and cardiovascular disorders, including myocardial infarction, stroke, and heart failure. Blood pressure may be influenced by either genetic and/or lifestyle factors including nutrition, smoking, high blood glucose and high body-mass index. Global mortality due to hypertension is currently over 30 million and may increase to 40 million annually by 2030.

Objectives: This research work was designed to evaluate the antihypertensive and electrolyte modulatory effect of ethanol extract of Terminalia catappa leaf following L-NAME induced hypertension in male Wistar rats.

Methods: In this present work, thirty- five (35) Wistar male rats was allowed to acclimatize for a period of 7 days, in a well-ventilated room at room temperature and relative humidity of 29°C and 70% respectively with 12 hours natural light-dark cycle Hypertension was induced by intraperitoneal administration of L-NG-nitro arginine methyl ester (L-NAME) (40 mg/kgb.wt/day in distilled water. Treatment was carried out as follows: group 1 (normal control) received only the vehicle (Normal saline) orally, group 2 (hypertensive control) received L-NAME (40 mg/kgb wt/day) intraperitoneally for 2 successive weeks; group 3 ( standard control) L-NAME (40 mg/kgb .wt/day) +20mg/kg b.wt /day of amlodipine  while  group 4 and 5 (reference groups) received L-NAME + extract of T. catappa (200  and 400 mg/kg b .wt/day respectively for 2 successive weeks. Blood was collected by cardiac puncture under plane sterile tubes for serum electrolytes and lipid profile.

Results: The result displayed that T. catappa leaf produced a significant (p<0.05) decrease in serum Na+, K+, Ca2+, Cl- ion concentration when compared with normotensive and hypertensive. The extract significantly (p<0.05) increased serum HDL and triacyl glycerides, but lowered the serum LDL, total –cholesterol when compared with normotensive, hypertensive and standard control.

Conclusion: It can be inferred from this present work that extract of Terminalia catappa might inhibit predisposition to hypertension and/ or contain some bioactive compounds with antihypertensive effect and might be useful in the management of pathological conditions associated with cardiovascular dysfunction possibly by deactivation of either the brain renin–angiotensin–aldosterone system (RAAS) or sympathetic nervous system.