Phosphohexose Isomerase (PHI) and Porcine Halothane Sensitivity

Malignant hyperthermia is a serious consequence of halo-thane anaesthesia in predisposed animals and humans. In view of the similar clinical-biochemical symptoms in humans as well as in pigs susceptible to halothane anaesthesia, the stress susceptible pig appears to be a useful animal model for study of this abnormal condition and for development of non-destructive detection methods for its identification.     

Niche segregation of terrestrial alpine beetles (Coleoptera) in relation to environmental gradients and phenology

At Finse, south Norway (60°36'N, 7°30'E), 247 pitfall traps were set in forty-seven alpine habitats. More than 21,000 individuals were caught, including thirteen species of Carabidae, forty-six Staphylinidae and twenty-eight species from other families. The locations were selected to maximize variation in soil water contents between the habitats, but minimize variation in time of snowmelt and aspect. Soil water content of the sites was highly correlated with soil organic content, and showed little variation between dry and rainy periods. A reciprocal averaging (RA) ordination of the sites and coleoptera species gave results similar to a direct gradient analysis based on soil water content of the sample sites, clearly showing the importance of habitat humidity. Riverside and mire habitats had the most distinct species composition. Niche segregation among the species was studied based on guild, soil humidity preference, seasonal activity pattern and altitudinal range. Most species were well separated along one or more of these niche dimensions. No species from the wettest habitats were autumn active, otherwise all permutations of the described niche dimensions were used. Carabids and herbivores from various families were all spring active, while 38% of the staphylinids, mainly in the subfamily Omaliinae, were autumn active. In cases where species were not clearly separated, their behaviour, morphology, size, diet, etc. were considered.     

Exocrine secretion of epidermal growth factor from Brunner's glands. Stimulation by VIP and acetylcholine

Brunner's glands of the duodenum are innervated by cholinergic and VIP-ergic nerves, and the glands have been shown to contain epidermal growth factor (EGF). In this study the effect of VIP and acetylcholine (Ach) on secretion of EGF from Brunner's glands was investigated in the rat. Intravenous infusion of VIP stimulated the flow rate of duodenal secretion, an effect which was inhibited by atropine. Ach alone did not significantly increase flow rate, and combined infusion of VIP and Ach induced the same flow as VIP alone. Concentration of EGF in duodenal secretion was increased by infusion of Ach, and this effect was potentiated by VIP. Infusion of VIP alone did not influence EGF concentration. EGF output from Brunner's glands was significantly stimulated by i.v. infusion of VIP and of Ach and combined infusion further increased EGF output. The study has demonstrated exocrine secretion of EGF from Brunner's glands, and it is suggested that stimulation is mediated by interaction of neuronal VIP and Ach.     

Histochemigal Detection of Copper in the Liver from Sheep Chronically Poisoned by Copper

Continued ingestion of copper in excess of the nutritional requirement leads in all animals to its passive accumulation within the tissues, especially the liver. Up to certain levels varying greatly with the species high concentrations of copper in the liver appear to impose no physiological hardship on the animal. Above these levels there may occur a catastrophic liberation of a high proportion of the copper into the blood stream resulting in extensive hemolysis and jaundice usually followed by death. Sheep are more prone to the hemolytic crisis of chronic copper poisoning than other animal species. The hemolytic crisis of chronic copper poisoning is associated with centrolobular necrosis of the liver. The copper concentration in the liver is usually 300 p.p.m. or more (wet tissue) compared with about 50 p.p.m. in normal sheep (Simesen & Møller 1969).