**4. Discussion**

124 Sexual Dysfunctions – Special Issue

4.46 5.73 6.69 7.73

Total 24 6.68 0.98 0.22

Total 24 3.66 0.69 0.17

Total 24 78.34 35.20 7.84

 Total 24 53.16 35.45 6.84 Table 1. Descriptive statistics, protein and some liver enzymes assay of groups.

> 17.612 1.978 18.282

7.749 1.881 8.976

19421.463 5627.238 25570.766

13873.376 5724.897 18.898

13.60 58.70 79.82 88.57

32.42 73.84 108.66 112.73

2.83 3.45 4.31 5.23

Protein (g/dl) Control

Albumin (g/dl) Control

ALT (μmol/l) Control

AST (μmol/l) Control

Protein Between Groups

Total

Albumin Between Groups

Total

ALT Between Groups

Total 

AST Between Groups

Total

*P* <0.0001

Within groups

Within groups

Within groups

Within groups

Table 2. Analysis of Variance (ANOVA) of the Four Groups

Exp. A Exp. B Exp. C

Exp. A Exp. B Exp. C

Exp. A Exp. B Exp. C

Exp. A Exp. B Exp. C

Group N Mean Std. Deviation Std. Error

0.59 0.21 0.37 0.42

0.38 0.26 0.29 0.34

0.51 11.63 27.03 29.42

0.61 8.84 29.37 32.62

Source of Variation Sum of Squares df Mean Square F Sig.

3 21 24

3 21 24

3 21 24

3 21 24 8.560 0.096

3.471 0.083

9823.571 302.135

6936.688 301.310

0.19 0.04 0.10 0.12

0.16 0.07 0.09 0.13

0.26 4.34 8.60 9.71

0.28 3.16 9.90 11.72

91.528 .000

60.21 .000

31.791 .000

23.022 .000

The results of the histological studies revealed that with increasing dose of Sildenafil citrate consumption, there were varying degrees of dilatations of the central vein of the liver which contained lysed red blood cells in the treatment group compared to the control sections of the liver, and as well as varying degree of cyto-architectural distortion and reduction in the number of renal corpuscle in the kidneys of the treated groups compared to the control sections of the kidneys. This suggests that the distortion of the cyto-architecture of the liver could be associated with functional changes that may be detrimental to the health of the rats. The proliferating cells of the liver, which produce red and white blood cells, are normally found between the hepatic cells and the walls of the vessels (Singh, 1997).

As a result of the distortion and dilatation of the hepatocytes and their central vein, the haematopoietic function of the liver may have been highly affected as a result of probable toxic effect of Sildenafil citrate. This was further buttressed by the increase in the liver enzymes obtained in the test group. In addition, total protein and albumin increased in this study the increase in total protein may be due to the fact that Sildenafil citrate was given for a short period of time. The resultant effect is acute toxicity leading to enhanced hepatocellullar activity and increase in globulin and albumin components of the protein .However, with prolonged usage, hepatic necrosis is likely to occur with a resultant low albumin levels. There were several diffuse degeneration and necrosis of the tubular epithelial cells in the kidneys of the treated animals. The degenerative and atrophic changes where observed more in the kidneys of rats that received the highest dose (1.43mg/kg) of Sildenafil citrate.

It may be inferred from the present results that higher doses of Sildenafil citrate consumption may have resulted in degenerative and atrophic changes observed in the renal corpuscle. The possible deduction from these results is that secondary metabolites, which are largely responsible for therapeutic or pharmacological activities of medicinal plants (Perry, 1980), may also account for their toxicity when the dosage is abused.

Pathological or accidental cell death is regarded as necrotic and could result from extrinsic insults to the cell as osmotic thermal, toxic and traumatic effect (Farber et al, 1981). Physiological cell death is regarded as apoptotic and organized programmed cell death (PCD) that is mediated by active and intrinsic mechanisms. The process of cellular necrosis involves disruption of membranes, as well as structural and functional integrity. Cellular necrosis is not induced by stimuli intrinsic to the cells as in programmed cell death (PCD), but by an abrupt environmental perturbation and departure from the normal physiological conditions (Farber et al, 1981).

Cellular degeneration has been reported to result in cell death, which is of two types, namely apoptotic and necrotic cell death. These two types differ morphologically and biochemically (Wyllie, 1980). Pathological or accidental cell death is regarded as necrotic and could result

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The limitation of this study was the duration of study (acute) as opposed to chronic which could have yielded more light on the pathology.

#### **5. Conclusion**

The results obtained in this study following the administration of 0.25mg/kg, 0.70mg/kg and 1.43mg/kg per day of Sildenafil to adult Wistar rats affected the histology of the liver and kidneys. These results suggest that the functions of the liver and kidney may have been adversely affected. It is recommended that caution should therefore be advocated in the intake of this product and further studies be carried out to examine these findings.

#### **6. References**


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