Effects of ethanol on chicks in vivo and on chick embryo tibiae in organ culture

Effects of ethanol on brain and pancreas weights, serum sodium and potassium, and haematological parameters in quail (Coturnix coturnix japonica)

Poultry farmers in Pakistan use ethanol for treatment of respiratory diseases and as a growth promotant, but the effects on health and production of broilers are unknown. The effects of ethanol were investigated in quail at different doses through drinking water. One hundred and twenty Japanese quail of 39 days of age were purchased from a local market. They were divided randomly into five groups of 24 (groups 1, 2, 3, 4 and 5) and offered ethanol at dose rates 2%, 4%, 8% and 16%, respectively, while group 5 served as control. Quail offered 8% and 16% ethanol showed dullness, depression and staggering gait, while those given 2% and 4% ethanol showed decreased responsiveness for 2 to 3 h. The live weight, brain volume along with serum sodium and potassium decreased significantly (P<0.05) in all treated groups, while there was significant (P<0.05) increase in relative weight of the pancreas. The decrease in live weight varied from 3% to 35% in a dose-related manner. The brain weight decreased by 4% to 10% and the decrease was dose dependent. Brain volume showed a 25% to 51% decrease. The haematological parameters erythrocyte count, packed cell volume and haemoglobin concentration increased significantly (P<0.05), while the leukocyte count increases were not significant. Both serum sodium and potassium decreased in ethanol-treated groups (36% to 44% and 44% to 49%, respectively), almost in a dose-dependent manner. The results suggest that ethanol at these dose levels has significant deleterious effects on haematology, brain volume and serum electrolytes.

Electromagnetic modulation of biological processes: influence of culture media and significance of methodology in the Ca-uptake by embryonal chick tibia in vitro

The present studies are aimed at establishing molecular correlations in the interaction of very low frequency electromagnetic fields with biological systems. Ca-uptake by chick embryo tibia rudiment in short-term culture was a useful model. Tibiae of 8- to 10-day-old chick embryos were incubated 60 min in simplified culture media in the presence of 45Ca at 37.5 +/- 0.5 degrees C either inside or outside pulsating electromagnetic fields. Radioactivity count in the medium was the most accurate method for determining Ca-uptake by the rudiment. The effect of the fields on the Ca-uptake depended markedly on the chemical composition of the culture medium: bicarbonate was indispensable; glucose or sucrose was important; phosphate was potentiating; ethanol, Mg2+, and NaF were stimulating. The field had no effect in (a) blank medium without tibia, (b) tibiae that had been altered by fixation with aqueous glutaraldehyde, (c) nonliving artificial systems endowed with great or small ion sorption capacity. The unique bicarbonate effect with living systems and the passive behavior of nonliving ion sorbing systems prompt the suggestion that the electromagnetic field probably couples with specific processes, such as a bicarbonate-dependent Ca2+ ATPase and the active ion transport, at the cell membrane level. The molecular mechanisms remain to be established.

Inhibition of net calcium efflux from bone by ethanol in vitro

Ethanol administered to animals is known to cause hypocalcemia. This investigation was undertaken to evaluate direct early effects of ethanol on the net fluxes of Ca2+ and inorganic phosphate (Pi) into or out of bone using tibiae from 13-day-old chick embryos and 8-day-old suckling rats in vitro. When chick bones were incubated with ethanol in the medium (10 microliters/ml), net Ca2+ efflux was decreased 19, 22, 27, and 31% at 2, 4, 6, and 8 h, respectively. Metabolically inhibited bones showed a net influx rather than efflux of Ca2+ and were not further affected by ethanol. The ethanol had no consistent effect on net Pi efflux and slightly reduced lactate production. At three doses of ethanol (3, 10, and 30 microliters/ml of medium) the reduction of Ca2+ efflux was dose related in both chick and rat bones. Ethanol completely inhibited parathyroid hormone-stimulated, net Ca2+ efflux from chick bones, even at ethanol levels that by themselves did not affect Ca2+ efflux. These findings are consistent with the hypothesis that the hypocalcemia in ethanol-treated animals may be due in part to inhibition of net Ca2+ efflux from bone.

Magnesium and the mineral metabolism of chick embryo tibiae in organ culture

Using bone organ culture techniques, three concentrations of magnesium were evaluated for their effects on the mineral mass of embryonic chick tibiae incubated for 3 days with or without a metabolic inhibitor (1 mM iodoacetic acid) added to the media. Varying the medium Mg level from 0.3 to 3.0 mM had little effect on the net increase in mineral in live bones (without the inhibitor), but in dead tibiae (with the inhibitor) there was a marked net decrease in mineral deposition with increasing Mg concentration. Bone Mg mass varied directly with the level of Mg in the medium regardless of whether or not the tibiae were inhibited. Responsiveness to parathyroid hormone (PTH) with regard to mineral loss and increased lactate production was not affected by Mg even in tibiae incubated in Mg-free media. However, PTH-treated bones cultured in Mg-free media had a significantly elevated Mg mass, suggesting that the hormone may have a Mg-conserving effect on bone during severe Mg deficiency. The findings of this study support the hypothesis that bone cells regulate the level of Mg to which newly forming mineral is exposed and that PTH-responsiveness in embryonic chick tibiae is not dependent on the ambient Mg concentration.