This work is to check for the renal protective effect of ginger on rats which were given nitrate-treated drinking water. 21 wistar albino rats were divided into four groups (A, B, C, D). Group A which contains 5 rats served as the control group. They were fed with normal feed and normal drinking water. Group B (made up of 6 rats) were fed with feed formulated with 2.4g of ginger and water treated with 400mg/l of NaNo3. Group C (containing 5 rats) were fed with normal feed and water treated with 400mg/l of NaNO3. Group D (containing 5 rats) were fed with feed formulated with 2.4g of ginger and 2% ascorbic acid, and water treated with 400mg/l of NaNo3. Kidney function tests-urea and creatinine, were carried out on the blood samples of all the 4 groups. The results of the analysis were as follows: urea level; for group A (control) = 4.42mmol/l; group B (nitrate + ginger) = 6.03mmol/l, group C (nitrate only) = 5.36mmol/l, group D (nitrate + ascorbic acid = 6.06mmol/l. creatinine level; group A (control) = 96µmol/l, group B = 106.33µmol/l, group C = 105.4µmol/l, group D = 92.2µmol/l. Using creatinine which is strong biomarker for kidney dysfunction, there was no significant difference between the normal control and the treatment groups (p>0.05). So 400mg/l level of nitrate administered to the rats did not have significant adverse effect on them and the 2% ginger helped in the proper functioning of the kidney as shown in their increased final weights.
1.1 BACKGROUND OF STUDY
GINGER- Ginger (Zingiber officinale Roscoe, Zingiberaceae) is one of the most commonly consumed dietary condiment in the world (Surh et al.,1999 ). The oleoresin (i.e., oily resin) from the rhizomes (i.e., roots) of ginger contains many bioactive components, such as -gingerol (1-[4′-hydroxy-3′-methoxyphenyl -5-hydroxy-3-decanone), which is the primary pungent ingredient that is believed to exert a variety of remarkable pharmacological and physiological activities. Although ginger is generally considered to be safe (Kaul and Joshi, 2001), the lack of a complete understanding of its mechanisms of action suggests caution in its therapeutic use (Wilkinson 2000a ). Previous reviews (Barrett et al., 1999; Ness, Sherman, and Pan 1999 ; Talalay and Talalay, 2001) have emphasized the importance of careful scientific research in establishing the safety and efficacy of potential therapeutic plant remedies and in defining the risks and benefits of herbal medicine. Ginger has been used for thousands of years for the treatment of numerous ailments, such as colds, nausea, arthritis, migraines, and hypertension. The medicinal, chemical, and pharmacological properties of ginger have been extensively reviewed (Surh, et al., 1998; Ernst and Pittler 2000 ; Afzal et al., 2001).
NITRATE – In recent years, considerable attention has been paid to the problem of nitrate due to the intensive use of nitrates as agricultural fertilizers which reach to humans and animals by different routs ( Manassaram, Backer, and Moll, 2006; Mande et al., 2012 ). Nitrate is a naturally occurring form of nitrogen and is an integral part of the nitrogen cycle in the environment. It is formed from fertilizers, decaying plants, manure and other organic residues. Nitrate is found in air, soil, water, and vegetables food and is produced naturally within the human body (Ogur et al., 2005 ). The presence of nitrate in vegetable as in water and generally in other foods is a serious threat to man’s health. Nitrate per se is relatively non toxic (Mensinga, et al., 2003),but approximately 5% of all ingested nitrate is converted by microflora in the gastrointestinal tract to the more toxic nitrite ( Pannalaet al., 2003 ). Nitrite and N- nitroso compounds which form when nitrite binds to other substances before or afteringestion are toxic and can lead to severepathologies in humans ( Speijers and van denBrandt, 2003).
1.2 AIM OF THE STUDY
To determine the renal protective effect of ginger on rats fed with drinking water containing nitrates.
1.3 OBJECTIVE OF THE STUDY
To evaluate the effect of nitrate on rat kidney and the protective effect of ginger against kidney dysfunction.