Usually practicing veterinarians and animal keepers have to deal with inadequate supplementation of copper which causes deficiency diseases. However, instead of curing, the consequential intake of copper is likely to cause copper intoxication. Copper poisoning is observed particularly frequently, in sheep - the most sensitive domestic animal to copper toxicity. In most cases, sheep undergo chronic exposure to copper causing liver necrosis and resulting in massive haemolysis, haemoglobinuria and eventually in renal failure. The observed symptoms have an acute character and a set of them is called haemolytic crisis. The pathogenesis, signs and diagnosis of this syndrome are described in this article.
The aim of this research was to study the possibilities of using papaverine as a reference substance to control the ability of isolated gastrointestinal (GI) tract strips to relax. The effects of papaverine hydrochloride (0.001-100 µM) dissolved in distilled water, or in DMSO (0.5%), on the mechanical activity of isolated rat GI strips (stomach fundus and corpus, duodenum and jejunum) were studied. The obtained results show that papaverine provoked various responses of the examined muscle strips dependent on the part of GI tract and papaverine solvents used (water or DMSO). Papaverine applied as water solution caused muscle relaxation of all investigated gastrointestinal strips: the lowest effective (induced relaxation) concentration of papaverine was 10 µM for gastric corpus, jejunum and duodenum and 100 µM for gastric fundus. However, there was no dependence between the concentration of papaverine and the degree of muscle relaxation of the studied GI strips. Moreover, in case of gastric fundus strips, papaverine applied as 0.5% DMSO solution provoked different muscle responses: in the presence of 0.1 and 1 µM papaverine contraction occurred; administering papaverine at higher concentrations (10 and 100 µM) resulted in relaxation. The obtained results clearly indicate that papaverine does not fulfil the criteria set for the reference substance and should not be used as an indicator for controlling of gastrointestinal tract muscle relaxation in vitro.
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