1 Effects of an aqueous extract of Sansevieria senegambica on plasma marker enzymes (U/L) of salt-loaded rats. http://sajs.co.za/index.php/SAJS/article/downloadSuppFile/481/2821
Table 2 shows the effect of an aqueous extract of the leaves of S. senegambica on the plasma chemistry of salt-loaded rats. The plasma creatinine concentration of test group 1 was significantly lower (p < 0.05) than that of the control and test control groups, but not different from the reference and test 2 groups. There were no significant differences in plasma urea, total bilirubin, conjugated bilirubin, unconjugated bilirubin, albumin and unconjugated to conjugated bilirubin ratios between the groups. The plasma total protein concentrations of the test groups were not significantly different from that of the control, test control or reference groups, although plasma total protein was significantly lower (p < 0.05) in test group 1 than in test group 2. No negative effects on liver and kidney functions of the test animals (Tables 1 and 2) were observed as a result of administration of the extract.
2Effects of an aqueous extract of the leaves of Sansevieria senegambica on the plasma chemistry (mg/dL) of salt-loaded rats. http://sajs.co.za/index.php/SAJS/article/downloadSuppFile/481/2822
The effects of an aqueous extract of the leaves of S. senegambica on the plasma electrolyte levels of salt-loaded rats are shown in Table 3. There were no significant differences in the plasma bicarbonate concentrations between the groups. The plasma calcium levels of the test groups were significantly higher (p < 0.05) than those of the test control and reference groups. Plasma calcium levels of test group 1, but not those of test group 2, were also not significantly different from that of the control group. The plasma chloride and sodium levels of the test groups were significantly lower (p < 0.05) than those of the test control and reference groups, but not different from those of the control group. The plasma potassium levels of the test groups were significantly higher (p < 0.05) than those of the test control and reference groups, but not different from those of the control group.
3Effects of an aqueous extract of the leaves of Sansevieria senegambica on the plasma electrolyte levels (mmol/L) of salt-loaded rats. http://sajs.co.za/index.php/SAJS/article/downloadSuppFile/481/2823
This study confirms earlier reports by McCarron 20and Young et al. 21, that the concentration of calcium in body fluids and its handling by cellular proteins are disturbed in patients and experimental animals with arterial hypertension. The extract countered the lowering of plasma calcium levels induced by salt-loading. It may have achieved this by altering parathyroid hormone secretion. The raised plasma calcium may, in turn, have great impact on arterial muscle tone, because cardiac muscle relies on extracellular calcium for contraction. 22In healthy animals, there is a direct relationship between myogenic tone in isolated arteries and blood pressure. 23Therefore, the basis of the antihypertensive activity of the extract may be through moderation of muscle tone, brought about by increases in plasma calcium concentration. This is in turn modulated by reducing the entry of calcium into the cells or increasing its removal from the cells into the extracellular space. One of the mechanisms of action of antihypertensive drugs, especially the diuretics, is the reduction of plasma sodium and chloride concentrations. 24,25 Antihypertensive therapy usually achieves this by diminishing the reabsorption of these electrolytes at different sites in the nephrons. Of note amongst these therapies are the potassium-sparing diuretics, which inhibit either aldosterone directly, or the Na+/K+ exchange mechanisms in the distal tubules and collecting ducts. 24,25 The overall effect is the loss of sodium in the urine and the retention of potassium in the blood, culminating in lowered plasma sodium and raised plasma potassium levels. In this study, the leaf extract produced reduced plasma sodium and increased plasma potassium levels. This finding suggests that the extract may have potassium-sparing diuretic effects and may also be a β-antagonist. Table 4 shows the effects of an aqueous extract of the leaves of S. senegambica on the haematological profile of salt-loaded rats. There were no significant differences in the packed cell volume, haemoglobin concentration, mean cell volume, and basophil and eosinophil counts. The mean cell haemoglobin concentration of test group 2 was significantly lower (p < 0.05) than that of the test control group, but not different from that of the control, reference or test 1 groups. The red cell count of the test control group was significantly lower (p < 0.05) than that of the control group, but not significantly lower than that of the reference and test groups. The mean cell haemoglobin of test group 2 was significantly lower (p < 0.05) than that of the reference group, but not significantly lower than that of the control, test control and test 1 groups. The total white cell count of test group 2 was significantly higher (p < 0.05) than that of the control, test control and reference groups, but not different from that of test group 1. The lymphocyte count of test group 1 was significantly higher (p < 0.05) than that of the control group, but not significantly different from that of the test control, reference or test 2 groups. The monocyte count of test group 2 was significantly lower (p < 0.05) than that of the test control group, but not different from that of the control, reference or test 1 groups. The neutrophil count of test group 1 was significantly lower (p < 0.05) than that of the control group, but not different from that of the test control, reference or test 2 groups.
4Effects of an aqueous extract of the leaves of Sansevieria senegambica on the haematological profile of salt-loaded rats. http://sajs.co.za/index.php/SAJS/article/downloadSuppFile/481/2824
The extract had no significant effect on the haemopoietic system of the rats, but raised the total white cell count whilst lowering the monocyte count. Drug poisoning and stress are among the main causes of raised white blood cell counts. According to reports from some experimental and pathological studies, white blood cells play an important role in the destabilising of coronary artery plaques at the onset of acute coronary syndrome. 25,26,27,28 Nevertheless, an elevated white blood cell count in peripheral blood is a known risk factor for coronary artery disease. 28,29,30 Therefore, the observed higher white blood cell count in the animals that received the extract has two implications: it implies either protection against the onset of acute coronary syndrome or increased risk of coronary artery disease. Conclusion Results from this study suggest that the extract may be a diuretic that causes leukocytosis without altering liver and kidney functions or activities of the haemopoietic system, at least at the doses at which it was administered in this study. This study also supports the use of S. senegambica in the management of hypertension, whilst suggesting that its antihypertensive activity may be mediated through alteration of plasma sodium and potassium levels, or increases in muscle tone brought about by changes in plasma calcium levels. Competing interests We declare that we have no financial or personal relationships which may have inappropriately influenced us in writing this article. Authors’ contributions All the authors participated in the planning and design of the research. C.C. Ikewuchi and J.C. Ikewuchi performed the experiments and wrote the manuscript, which was edited by E.N. Onyeike and E.O. Ayologu. 1.http://dx.doi.org/10.1001/archinte.165.18.20982.http://dx.doi.org/10.1016/S0140-6736(05)17741-13.http://dx.doi.org/10.1056/NEJMra064486174949294.AkinkugbeOOHypertensionAkinkugbe OONon communicable diseases in Nigeria: Final report of a national survey199712415.http://dx.doi.org/10.1097/00004872-200311000-00002145978366.http://dx.doi.org/10.1038/sj.jhh.100072299287487.IkeSOIkehVOThe prevalence of diastolic dysfunction in adult hypertensive Nigerians200640255601729956717908408.2007 ESH-ESC Practice Guidelines for the Management of Arterial Hypertension ESH-ESC Task Force on the Management of Arterial Hypertension200725175117629.KambojVPHerbal medicine200078355110. http://dx.doi.org/10.1186/1476-511X-6-1117419879185255611.BaiyewuOTraditional medicine and health care2001528428812.The promotion and development of traditional medicine197813.Agricultural Research Service, Germplasm Resources Information Network (GRIN). GRIN taxonomy for plants [database on the Internet]c2008 cited 2008 Jul 2314.ObiefunaPCMSofolaOAEbeigbeABDietary salt-loading attenuates endothelium dependent relaxation in response to histamine but not to acetylcholine in rat aortic rings199176135138201507015.NwaigweCISofolaOAPotassium but not nifedipine reduces hypertensionin anaesthetized salt loaded rats19891776776816.HolmeDJPeckHAnalytical biochemistry. 3rd ed199817. BaginskyESMarieSSClarkWLZakBDirect microdetermination of calcium1973464954473288818.CheesbroughMDistrict laboratory practice in tropical countries, part 2200419. SPSS Statistics200820. http://dx.doi.org/10.1056/NEJM198207223070405708807121.YoungEWBukoskiRDMcCarronDACalcium metabolism in experimental hypertension1988187123141327719322.MurrayRKMuscle and the cytoskeletonMurray RK, Granner DK, Mayes PA, Rodwell VW200357955623.http://dx.doi.org/10.1152/ajpregu.00819.20051646749824.RangHPDaleMMRitterJMMoorePKPharmacology. 5th ed200525.CrookMAClinical chemistry and metabolic medicine. 7th ed200626. MorenoPRFalkEPalaciosIFNewellJBFusterVFallonJTMacrophage infiltration in acute coronary syndromes: Implications for plaque rupture1994902775778804494727. Van der WalACBeckerAEVan der LoosCMDasPKSite of intimal rupture or erosion of thrombosed coronary atherosclerotic plaques is characterized by an inflammatory process irrespective of the dominant plaque morphology19948913644828167028.LibbyPCurrent concepts of the pathogenesis of the acute coronary syndromes200110433653721145775929.http://dx.doi.org/10.1536/jhj.44.2011271848230. http://dx.doi.org/10.1016/j.amjhyper.2006.10.00717386341