1. Petroleum Contamination Altered Neuromuscular Function and Structural Integrity in the Sciatic Nerve-Gastrocnemius Muscle Preparation of Toad.
Anigbogu C.N., Idowu A. J., Anunobi C.C.
Gasoline (petrol) and other petroleum products are in increasing use among the populace. Environmental contamination due to oil exploration, exploitation, distribution and even criminal vandalisation have increased contact and exposure to these products. Indiscriminate abuse of petrol is not limited to automechanics that suck it with the mouth, wash hands and legs with it, it also extends to those who use it as solvents, sniff it for ‘pleasure’, or use it as insect repellent. We have therefore investigated the effects of gasoline on neuromuscular function. The toad sciatic nerve and gastrocnemius  muscle was used. The tissues were placed in a muscle bath containing 50ml of amphibian ringer solution. Graded concentration of gasoline was introduced into the tissue bath for ten minutes. The preparations were stimulated through the nerve and threshold voltage, maximal voltage, latent period, contraction and relaxation profiles were recorded using the Kymograph (Harvard Apparatus). Results from this study show that 0.4% – 2.0% concentration of petrol had significant effect on velocity of shortening, height of contraction and contraction period (p<0.05). Lower concentrations increased motor activity with little or no effect on threshold or maximal voltages, absolute refractive period and relaxation period. At 4.0% concentration all neuromuscular activity ceased. Histological investigations revealed tissue damage, disruption of membranes and infiltration and tissue oedema. Therefore it is concluded that petrol may have a toxic effect on neuromuscular structure and function.

2. Decreased Brain Serotonin Level in Adjuvent Induced Arthritic Rats.
Khan Moona Mehboob,Sultana Najma, Arayne M. S, Saleem . M.Darakhshan.
Rheumatoid arthritis is an autoimmune disorder in which patient not only suffered from joint misery but  also face its associated depression. Objectives: To determine brain serotonin levels in adjuvant-induced arthritic (AIA) rats as its decrease concentration contribute to make body depressed. Methodology: AIA was induced in female SpragueDawley rats. Paw volumes was measured to evaluate arthritic progression while brain serotonin was estimated by HPLCEC method. Data was analyzed by student t-test. Results: Significant reduction (p<0.005) in all brain serotonin level was found in arthritic rats when compared with normal. Conclusion: Brain serotonin level decreases in AIA rats which may  be one of the reasons of its depression.