Intoxicação natural por Solanum glaucophyllum (Solanaceae) em búfalos no Pantanal Matogrossense / Natural poisoning by Solanum glaucophyllum(Solanaceae) in buffaloes in the Brazilian Pantanal

Descreve-se a ocorrência de calcinose enzoótica em búfalos no município de Poconé, Mato Grosso, associado ao consumo de Solanum glaucophyllum (Sg) [=Solanum malacoxylon]. Os casos foram observados entre os anos de 2007 e 2009. Em um rebanho de 40 búfalos, cinco apresentaram emagrecimento progressivo, dorso arqueado, marcha rígida, por vezes com dificuldade para se levantar e locomover, permanecendo apoiando sobre os carpos.Três animais recuperaram-se parcialmente e dois foram eutanasiados in extremis. Os principais achados de necropsia foram calcificação de tecidos moles, principalmente em artérias de grande e médio calibres. A presença de S. glaucophyllum nas pastagens, os sinais clínicos, além dos achados ultrassonográficos e patológicos envolvendo múltiplas calcificações de tendões e outros tecidos, são compatíveis com intoxicação por Solanum glaucophyllum.

This report describes the occurrence of enzootic calcinosis in buffaloes in the municipality of Pocone, Mato Grosso, due to the consumption of Solanum glaucophyllum (Sg) [=Solanum malacoxylon]. The cases were observed in the years 2007 and 2009. In a herd of 40 buffaloes, five showed weight loss, arched back, stiff gait, sometimes difficulty to raise and walk, and leaning on the carpus. Three buffaloes recovered partially and two were euthanized in extremis. The main necropsy findings were calcification of soft tissues, especially of large and medium arteries. The presence of S. glaucophyllum in the pasture, clinical signs, in addition to the sonographic and pathologic calcification involving tendons and other tissues, are consistent with Solanum glaucophyllum poisoning.

Effect of bamboo shoot, Bambusa arundinacea (Retz.) Willd. on thyroid status under conditions of varying iodine intake in rats.

Young shoots or sprouts of common bamboos are used as food in third world countries. Evidences suggest the presence of cyanogenic glucoside like anti-thyroidal substance in bamboo shoots (BS) but effect of prolonged BS consumption on thyroid status under conditions of varying iodine nutriture remains unexplored. The study was undertaken to evaluate goitrogenic content, in vitro anti thyroid peroxidase (TPO) activity and in vivo anti thyroid potential of BS with and without extra iodide. Fresh BS contains high cyanogenic glucoside (551 mg/kg), followed by thiocyanate (24mg/kg) and glucosinolate (9.57mg/kg). In vitro inhibition in TPO activity was found with raw, raw boiled and cooked extracts. Inhibition constant (IC50) and PTU equivalence of fresh BS were 27.5+/-0.77 microg and 3.27 respectively. Extra iodide in the incubation media reduced TPO inhibition induced by BS but could not cancel it. Thyroid weight, TPO activity and total serum thyroid hormone levels of BS fed animals for 45 and 90 days respectively were determined and compared with controls. Significant increase in thyroid weight as well as higher excretion of thiocyanate and iodine along with marked decrease in thyroid peroxidase activity, T4 and T3 levels were observed in BS fed group. Chronic BS consumption gradually developed a state of hypothyroidism. Extra iodide had reduced the anti-thyroidal effect of BS to an extent but could not cancel it because of excessive cyanogenic glucoside, glucosinolate and thiocyanate present in it.

Effect of potassium channel modulators on toxicity of Cleistanthus collinus.

The study was conducted to determine the effects of boiled extract of Cleistanthus collinus on rats by observing ECG changes and electrolyte levels in serum and urine. Influence of minoxidil and glibenclamide on Cleistanthus collinus induced toxicity was determined. ED50 for arrhythmia, changes in contractility and heart rate were recorded using the isolated frog heart. Cleistanthus at low doses caused transient tachycardia and increase in contractility and at high dose caused arrhythmia and cardiac arrest in rat. LD50 was found to be 1690 mg/kg. Minoxidil potentiated cardiac toxicity, whereas glibenclamide did not produce any significant change. High concentration of potassium in Cleistanthus extract hindered comparison of its levels. There was excretion of sodium even in the presence of hyponatraemia. Cleistanthus at low dose caused transient tachycardia and increase in contractility and at high dose caused arrhythmia and cardiac arrest in isolated frog heart. ED50 for arrhythmia was found to be 1406 mg/kg. Acute toxicity was mainly due to depressive cardiac activity of Cleistanthus. It also caused renal failure. Potassium channel modulators did not have important role in acute cardiac toxicity treatment. Probably in chronic toxicity, electrolyte level changes are involved and potassium channel modulators might have a role.

Neurolytic manifestation of piscicidal flavanoid of plant, Engelhardtia colebrookiana (Lindle) in fish.

The sublethal concentration 6 mg.l-1 of a piscicidal flavanoid, 'Quercetin glycoside', obtained from E. colebrookiana affected neuro-architecture in medulla oblongata of freshwater fish, Barilius bendelisis (Ham.), at 32 days exposure. Since medulla of fish is primary centre for the reception of several incoming stimuli, the breakdown of neurons and their neuraxes in facial and vagal lobes impaired the transmission of sensory informations to cerebellum. Consequently fish became unconscious and could be caught easily with hands. The symptoms like lack of schooling, lack of response to food and external stimuli, sluggishness, incapability of maintaining body posture and uncoordinated functioning are accounted for by the neurolysis in hind brain of fish.