Scientific Research and Essays Vol. 2 (4), 105-111, April 2007          
ISSN 1992-2248 © 2007 Academic Journals

Full Length Research Paper

Effects of phenylalanine and glycine on some toxic effects of chloramphenicol

Esimone, C. O¹, Nworu C. S²*, Ekechukwu A. C³ and Awemu A. G⁴

¹Department of Pharmaceutics, University of Nigeria, Nsukka, 410001, Enugu State, Nigeria.

²Department of Pharmacology and Toxicology, University of Nigeria, Nsukka, 410001, Enugu State, Nigeria.

³Division of Physiology and Pharmacology Technique, Department of Science laboratory Technology, University of Nigeria, Nsukka, 410001,Enugu State, Nigeria.

⁴Department of Medicinal Chemistry, University of Nigeria, Nsukka, 410001,Enugu State, Nigeria.

*Corresponding author. E-mail: csnworu@yahoo.com.  Tel : +234 8033501106.

Accepted 27 March, 2007

We investigated the effects of concurrent administration of the amino acids, phenylalanine and glycine, on chloramphenicol (CAP)-induced haematotoxicty and histopathological effects in rats infected with Klebsiella pneumonia. The study was carried out for 21 days in which haematological and histopathological changes were monitored in the infected animals treated with either of these amino acids or their combination and chloramphenicol. After 7 days of treatment, the amino acids suppressed the decreases recorded in anaemia-related haematological parameters. The order of potency is as follows: CAP/glycine > CAP/glycine/phenylalanine > CAP/phenylalanine > CAP alone > negative control. These decreases were significantly (P < 0.05) different from the pretreatment values. Increases in the white blood corpuscle (WBC) count were recorded in all the groups.  Phenylalanine and glycine reduced the proliferation of WBC, an indication of the ability to control progression of infections. The order for this activity is: CAP/phenylalanine/glycine > CAP/glycine > CAP/phenylalanine > CAP alone > control. With the exception of the group which received chloramphenicol alone, all other treatment groups exhibited increases or no changes in PCV, HB and RBC on day 21 relative to day 7 values. The WBC counts in all the animals in the treated groups were decreased, with CAP/glycine treated group being the most remarkable. Of all the combinations used in the study, only CAP/glycine was effective in protecting the liver against the toxic effects of CAP. No appreciable protection was noted in the spleen of any of the groups. Phenylalanine, glycine and their combination when given concomitantly significantly, reduced the anaemia and histopathological changes associated with chloramphenicol administration.

Key words: chloramphenicol toxicity, glycine, haematotoxicity, phenylalanine.