Biochemical and biological studies on the interaction of some food colorants and preservatives

This study aims to investigate the effect of some food colorants and preservatives on Sprague-Dawley albino rats. The study was conducted on six equal groups fed on either basal control diet [group 1] or experimental diets [groups 2-6] as following: groups 2, 3 and 4 received a standard diet containing beta-carotene, tartrazine or benzoic acid, respectively at a dose of 200 mg/kg diet, while groups Sand 6 received a standard diet containing benzoic acid [200mg/ kg diet] incorporated with beta-carotene or tartrazine [200mg/ kg diet], respectively. Animals were fed ad libitum for 45 days. Body weight, food intake, feed efficiency and some biochemical analyses were measured, also histopathological examination of liver was performed. Our results showed a significant increase in blood urea, serum creatinine, ALT, AST, ALP and bilirubin in all groups except that received beta-carotene. Liver glycogen showed a significant decrease in rats fed on tartrazine alone or in combination with beuzoic acid. The histopathological results showed no significant toxic effects of beta-carotene alone while when combined with benzoic acid, moderate congestion and necrotic degeneration occurred. Tartrazine also induced slight mononuclear infiltration and benzoic alone showed marked vaculation, while in combination showed marked congestion, vascular infiltration and vaculation. In conclusion, the present study showed that even the permitted doses of colorants [e.g. beta-carotene and tartrazine] and food preservatives [e.g. benzoic acid] when taken together or if taken in excessive quantity may be harmful

Effect of some opioids on plasma glucose and liver glycogen in STZ-induced diabetic rats

Opioid analgesics are used widely to control various types of pain. Several studies reported that opioid analgesics may produce lowering plasma glucose. The present work aims to investigate the effect of both tramadol and fentanyl on the plasma glucose and liver glycogen of streptozotocin [STZ] induced diabetic rats and declares the possible mechanism of this effect. IV administration of either tramadol or fentanyl for 4 successive days in STZ-induced diabetic rats produced significant reduction in fasting and random plasma glucose in comparison with non-treated STZ-induced diabetic rats. IV Naloxone [mu opioid [MOP] receptor blocker] 30 min. before administration of either tramadol or fentanyl blocked the effect of both tramadol and fentanyl on fasting and random plasma glucose. IV injection of both tramadol and fentanyl in STZ-induced diabetic rats for 4 successive days, produced significant recovery [increase] of glycogen content of the liver in diabetic rats compared with diabetic non-treated group. This effect was also blocked by IV naloxone administration 30 min before administration of either tramadol or fentanyl. The histochemical examination of PAS stained sections of the liver, prepared from rats used during this work, confirmed the results obtained by chemical detection of glycogen content of the liver homogenate. I.V injection of either tramadol or fentanyl produced significant increase in pain tolerance. I.V naloxone 30 min. before adminstration of either tramadol or fentanyl partially blocked the analgesic effect of tramadol, while the analgesic effect of fentanyl was completely blocked. These results suggested that both tramadol and fentanyl have a significant anti-hyperglycemic effect. This effect could be through activation of MOP receptors which may be mediated through increased glycogen deposition in the liver

Contribuiçäo ao estudo do glicogênio hepático em animais (Rattus norvergiccus albinus) tratados cronicamente con cânhamo da India / Contribution to the study of hepatic glycogen in animals (Rattus norvergicus albinus) chronically treated with the hump plant

O presente trabalho avalia o nível de glicogênio hepático em animais tratados cronicamente com cânhamo da India, injetados diariamente por via intraperitoneal. Em trabalhos anteriores observa-se que esses animais apresentam hipoglicemia e näo esclarecem o fator determinante de tal alteraçäo. O objetivo deste trabalho, portanto, é determinar histologicamente possíveis alteraçöees á nível hepático, a fim de se verificar uma possível correlaçäo com a alteraçäo glicêmica