Poisoning in domestic cats in Brazil: toxicants, clinical signs, and therapeutic approaches / [Intoxicação em gatos domésticos no Brasil: toxicantes, sinais clínicos e abordagens terapêuticas]

This study evaluated the most common toxic agents affecting domestic cats, the clinical signs of toxicity, and the therapeutic approaches for recovery. A survey on poisoning in cats was conducted among small animal veterinary practitioners from 2017 to 2018. Of the 748 completed questionnaires, 543 (72.6%) were evaluated. Pesticides and household cleaning supplies were the most common causes of poisoning in cats. The toxicant groups included pesticides and household cleaning supplies (organophosphates), human drugs (acetaminophen), plants/plant derivatives (lily), and veterinary drugs (tramadol). The major clinical signs for these four groups of toxicants were (1) acetaminophen poisoning, which caused oxidative erythrocyte damage; (2) muscarinic and nicotinic cholinergic syndrome, which resulted from organophosphate poisoning; (3) acute kidney injury, which resulted from intoxication of lily; and (4) serotonin syndrome, which resulted from tramadol toxicosis. Interventions for treating poisoning in cats were based on the clinical presentation of animals. In the present study, the significant toxins identified to be dangerous for cats were characterized using the obtained data in Brazil as well as the main associated clinical signs and therapy recommended by veterinarians.(AU)

Objetiva-se com este trabalho caracterizar os principais toxicantes para gatos domésticos, bem como os prevalentes sinais clínicos e a terapêutica associada. Uma pesquisa sobre envenenamento em gatos foi realizada entre médicos veterinários no período de 2017 a 2018. Dos 748 questionários preenchidos, 543 (72,6%) foram avaliados. Pesticidas e domissanitários foram os principais causadores de intoxicação em gatos. Entre os grupos tóxicos, destacaram-se, na categoria pesticidas e domissanitários (organofosforados), medicamentos humanos (acetaminofeno), plantas e derivados de planta (lírio) e medicamentos veterinários (tramadol). Os principais sinais clínicos para os quatro grupos de substâncias tóxicas foram: (1) intoxicação por acetaminofeno, que causou dano eritrocitário oxidativo; (2) síndrome colinérgica muscarínica e nicotínica, resultante do envenenamento por organofosforado; (3) lesão renal aguda, causada pela intoxicação por lírio; e (4) síndrome serotoninérgica, resultante da exposição ao tramadol. As intervenções realizadas para o tratamento dos envenenamentos foram justificáveis mediante a apresentação clínica dos animais. Por meio dos dados obtidos, puderam-se caracterizar os principais tóxicos para gatos no Brasil, bem como os principais sinais clínicos associados e a terapêutica preconizada pelos médicos veterinários.(AU)

possible ameliorating effect of Nigella sativa oil on tramadol induced apoptosis in the motor area of rat cerebral cortex: a histological and immunohistochemical study

Tramadol is a centrally active analgesic commonly prescribed for moderate to severe pain. Thymoquinone, the major active component of the Nigella sativa oil, is characterized by its antioxidant properties. This study aimed to demonstrate the histological and p53-immunohistochemical changes induced by tramadol in the rat cerebral cortex and evaluate the potential role of N. sativa oil in the attenuation of these changes. Twenty-four male albino rats divided into three groups were used in this study. Group I was the control group. Group II was given repeated intraperitoneal injections of increasing doses of tramadol of 20, 40, and 80 mg/kg/day on the first, second, and third ten days of the study, respectively. Group III was given oral N. sativa oil 4 ml/kg/day, 30 min before each tramadol injection for 30 days. Paraffin sections of the frontal cortex motor area were prepared and stained with H and E and with an immunohistochemical stain using anti-p53 antibody. In group II rats, numerous shrunken pyramidal cells with acidophilic cytoplasm and deeply stained pyknotic nuclei were seen. Some of the granular cells appeared as ghosts with margination of chromatin. Homogeneous acidophilic masses containing fragmented deeply stained nuclei and surrounded by clear halos were also observed. The number of p53-positive cells was significantly higher compared with both group I and group III. In contrast, in group III, multiple pyramidal and granular cells appeared normal and the number of p53-positive cells was significantly less compared with group II. N. sativa oil and derived thymoquinone ameliorate tramadol-induced apoptosis in the motor area of the rat cerebral cortex

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

Liver and kidney toxicity in chronic use of opioids: an experimental long term treatment model.

In this study, histopathological and biochemical changes due to chronic usage of morphine or tramadol in liver and kidney were assessed in rats. Thirty male Wistar rats (180-220 g) were included and divided into three groups. Normal saline (1 ml) was given intraperitoneally as placebo in the control group (n = 10). Morphine group (n = 10) received morphine intraperitoneally at a dose of 4, 8, 10 mg/kg/day in the first, second and the third ten days of the study, respectively. Tramadol group (n = 10), received the drug intraperitoneally at doses of 20, 40 and 80 mg/kg/day in the first, second and the third ten days of the study, respectively. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), creatinin, blood urea nitrogen (BUN) and malondialdehyde (MDA) levels were measured in the serum. Liver and kidney specimens were evaluated by light microscopy. Serum ALT, AST, LDH, BUN and creatinin levels were significantly higher in morphine group compared to the control group. Serum LDH, BUN and creatinin levels were significantly increased in the morphine group compared to the tramadol group. The mean MDA level was significantly higher in morphine group compared to the tramadol and control groups (P < 0.05). Light microscopy revealed severe centrolobular congestion and focal necrosis in the liver of morphine and tramadol groups, but perivenular necrosis was present only in the morphine group. The main histopathologic finding was vacuolization in tubular cells in morphine and tramadol groups. Our findings pointed out the risk of increased lipid peroxidation, hepatic and renal damage due to long term use of opioids, especially morphine. Although opioids are reported to be effective in pain management, their toxic effects should be kept in mind during chronic usage.