An ethanol vapor concentration of 1.6 mmol/l was used to test the diurnal variations of the olfactory response in two groups of snails, which were adapted to different light-dark cycles. The results revealed that the olfactory sensitivity to stimulation with ethanol was significantly increased during the day-time, which corresponds to the scotophase of the light-dark cycle, to which the animals...

The effect of extremely low frequency magnetic fields (50 Hz, 0.5 mT) - ELF-MF, on phosphate metabolism has been studied in the isolated ganglions of the garden snail Helix pomatia, after 7 and 16 days of snail exposure to ELF-MF. The influence of ELF-MF on the level of phosphate compounds and intracellular pH was monitored by ³¹P NMR spectroscopy. Furthermore, the activity of enzymes involved ...

The ionic nature and pharmacological properties of the outward current activated by membrane depolarization were studied on isolated neurones of the snail Helix pomatia, placed in Na+- and Ca2+-free extracellular solutions and intracellularly perfused with K+-free solution ("nonspecific outward current"). It was shown that the amplitude and reversal potential of this current (estimated from ins...

Voltage clamp currents from medium sized ganglion cells of Helix pomatia have a fast transient outward current component in addition to the usually observed inward and outward currents. This component is inactivated at normal resting potential. The current, which is carried by K+ ions, may surpass leakage currents by a factor of 100 after inactivation has been removed by hyperpolarizing conditi...

The objectives of this study were (1) to determine cadmium (Cd) accumulation in the midgut gland of a land snail Helix pomatia L. inhabiting residential areas of the 14 largest cities in Poland, and (2) to examine whether the accumulated Cd exerted any toxic effects. The average accumulation of Cd in the midgut gland of snails, weighing 16-18 g, ranged from 7.00 to 87.3 µg/g dry weight (0.06-0....

In all aquatic molluscs examined (Anodonta—Picken, 1937; Haliotis—Harrison, 1962; Octopus—Potts & Martin, 1963), blood is filtered through the wall of the heart (or branchial heart appendages in Octopus) into the pericardium. The pericardial fluid passes to the kidney, where secretion and reabsorption modify it to form the final urine. In the terrestrial pulmonates, however (Achatina—Martin, Ha...

Individuals with the T blood group contain terminal serme !threonine-linked N-acetylgalactosamine residues in their blood cells. This is due to lack of UDP-D-galactose: D-N-acetyl galactosamine /9-D-galactosyl transferase from part of their red cells and probably from their leukocytes. We have established B lymphoblastoid cell lines from such an individual by in vitro infection of his lymphocyt...

The small-angle X-ray scattering of 1/10-size molecules (in 0.1 ionic strength Tris buffer pH 8.1) and 1/20-size molecules (in 0.1 ionic strength ethanolamine buffer pH 10.6) of a-hemocyanin of the snail Helix pomatia was studied. The radii of gyration, 8.7 nm and 8.0 nm for 1/10-size and 1/20-size molecules respectively, and the shape of the scattering curves indicate that both have a very ani...

K(+)-sensitive liquid ion-exchanger microelectrodes are shown to be capable of measuring concentration changes which occur on a millisecond time scale. However, some quaternary ammonium ions, such as tetraethylammonium and acetylcholine, are able to block electrode function when present in concentrations as low as 10(-4) to 10(-3) M. Changes in extracellular potassium concentration caused by sp...