I Nosiri, I Abdu-Aguye, M Hussaini, E Abdurahaman
acetazolamide, electrolyte, frusemide, irvingia gabonensis, urine
I Nosiri, I Abdu-Aguye, M Hussaini, E Abdurahaman. Leaf Extracts Of Irvingia Gabonensis Increase Urine Output And Electrolytes In Rats. The Internet Journal of Alternative Medicine. 2009 Volume 8 Number 2.
The diuretic effect of the ethanol extract of the leaves of
- ions. The 50 mg/kg extract produced an increase (P< 0.03) in Cl- excretion compared with the control likewise the 100 mg/kg with a significant (P<0.001) increase in Cl- excretion. Comparing the urinary excretion of electrolytes produced by the extract with acetazolamide, similar diuretic profile was observed like the pH and the increased excretion of HCO3
-. Frusemide, a high ceiling diuretic had no effect on HCO3
-, had a different pH but enhanced the urinary excretion of Na+, K+ and Cl-. These results suggest that the active ingredient(s) in the ethanol extract of
Materials and Methods
Adult albino rats of both sexes weighing between 170 – 230g were used in the study. They were obtained form the animal house of the Faculty of Pharmaceutical Sciences, Ahmadu Bello University Zaria, Nigeria. Before the commencement of the studies all animals were allowed to acclimatize to the laboratory environment for at least five days and within this period they were watched closely and observed for any clinical signs, body weight changes, water and feed consumption. The experiments were carried out in accordance with the Guidelines for Laboratory Procedures laid down by the Ahmadu Bello University Zaria Ethics Committee on Research as well as the internationally accepted principles regarding the care and use of animals for experimental techniques.
The leaves of
Preparation of plant extract
The plant leaves were obtained in large quantities and left to dry at room temperature for two days after which they were dried in an oven at 35 – 400 C for 36 hrs. After that some of the leaves were ground into a coarse powder. The powdered leaves were kept in an air-tight glass container and stored in a dry place. 100g of the powder was subjected to Soxhlet extraction for 20 hrs at 50 – 550 C. The extract was concentrated and dried under vacuum. The percentage yield of the 100 g powdered leaves of
Pharmacological evaluation for diuretic Activity
In this experiment, the animals were randomly divided into five groups of five rats. Acetazolamide and Frusemide were the standard drugs used to screen the effects of the extract for the diuretic studies. Both male and female albino rats (wistar strain) were fasted overnight prior to test and screened for diuretic activities using the ethanol extract dissolved in normal saline. The first and second groups were given 50 and 100mg/kg of the ethanol extract, third group Frusemide 5mg/kg, fourth group Acetazolamide 5mg/kg, and the fifth group 2ml of normal saline. Immediately after administration, all were paired and kept in a quiet room to avoid unnecessary disturbance inside different metabolic cages capable of collecting their urine in a graduated cylinder free from faecal contamination. The output of the urine was measured for 24hours at 3hrs interval and route of administration of saline, frusemide, acetazolamide and extract was oral. At the end of the 24 hours the urine excreted was pooled in each group and an aliquot taken for estimation of Na+, K+, Cl-, HCO3 - contents and pH expressed as mmol/litre.
Results are expressed as mean ± S.E.M. Statistical differences were analyzed using student’s t-test where P< 0.05 was considered significant. SPSS version 15 software program was used.
Diuretic effect of the leaf ethanol extract in rats
The results of screening the ethanol extract for diuresis are shown in Table 1, Fig.1 and Fig.2. The extract increased urine output after an hour but the response to frusemide and Acetazolamide was within the first 30 minutes. The control showed only slight increase in urine output in the day (Fig.1) Frusemide (5mg/kg) induced brisk diuresis which reached maximum after 30 minutes and stayed constant until after about 6 hours and then increased gradually for the next 24 hours. The extract (50 and 100mg/kg) on the other hand produced a continuous increase in urine volume throughout the period of the experiment (Fig.2). This is similar to the diuresis obtained with acetazolamide (Fig.1) which produced a significant (P<0.05) increase when compared with the control.
Table 1 shows the electrolyte changes observed in the cumulative urine output. Frusemide was seen to enhance the increased excretion of Na+, K+ and Cl-. The different doses of the extract (50 and 100mg/kg) enhanced the excretion of HCO3- with pH of 10 compared with control. This is similar to the effect of acetazolamide (carbonic acid anhydrase inhibitor) on HCO3- level in urine. 50mg/kg of the extract produced an increase (P<0.03) in Cl- excretion compared with the control likewise the 100mg/kg of the ethanol extract with a significant (P<0.001) increase in Cl- excretion. However, acetazolamide produced a significant increase (P<0.001) in Na+ compared with the control.
The term diuresis has two separate connotations: One refers to the increase in urine volume per se while the other to the net loss of solute (electrolyte) and water (Irwin, 1990) and these are involved in the suppression of renal tubular reabsorption of electrolytes. The evidence of a diuretic response was observed in the rats treated with frusemide (LaxisR), acetazolamide (Diamox R) and the extract. Frusemide inhibits electrolyte reabsorption in the thick ascending limb of loop of Henle. Micropuncture experiment has demonstrated a greatly enhanced excretion of Na+ and Cl- (Greger and Wangemann, 1987). Studies has shown that the high ceiling diuretics enhance the excretion of both Ca2+ and Mg2+ to an extent approximately equal to the increase in Na+ excretion and also causes a greater depletion of K+ (Sutton, 1985). Some of these were also observed in this study.
Acetazolamide is a potent reversible inhibitor of carbonic anhydrase. More than 99% of enzyme activity in the kidney is inhibited before physiological effects become apparent (Preisig, 1987).
As the reabsorption of water is reduced, volume of urine increases and pH of urine becomes alkaline. Also it increases urinary concentration of HCO3 - accompanied by increases in Na+ and K+ ions with a fall in concentration of Cl- ((Preisig, 1987). All these were observed with Acetazolamide and the different doses of the extract.
There was a greater excretion of Na+ with the 50mg/kg of the extract than with the 100mg/kg which gave a greater depletion of K+. This suggests that an increase in the dose of the extract can lead to hypokalemic alkalosis (Milton,1970) and this is in line with the pH of the urine but with the lower dose can lead to hyponatremia. The urine bicarbonate (HCO3 -) and chloride (Cl-) contents were almost the same (HCO3 - (90 and 80mmol/litre), Cl- (9 and 11 mmol/litre) ) for the 50 and 100mg/kg of the ethanol extract. The HCO3 - content was much higher than frusemide treated animals.
The 24 hour cumulative urine output induced by the extract was higher than that of the loop diuretic agent but lower than that of acetazolamide. Considering the definition given to diuretics in the first paragraph, frusemide, acetazolamide and ethanol extract fall into this category. The leaf extract of
From this investigation, the different doses of the extract showed that