We found strain differences in the ability of wild Alberta Lymnaea stagnalis to form long-term memory (LTM) following operant conditioning when L. stagnalis were collected from the wild and trained in the laboratory. Lymnaea stagnalis obtained from the Belly River watershed had an enhanced ability to form LTM compared with those from an isolated pond (referred to as Jackson snails). We therefor...

The resting membrane potential of the pacemaker neurons is one of the essential mechanisms underlying rhythm generation. In this study, we described the biophysical properties of an uncharacterized channel (U-type channel) and investigated the role of the channel in the rhythmic activity of a respiratory pacemaker neuron and the respiratory behaviour in adult freshwater snail Lymnaea stagnalis....

The great pond snail, Lymnaea stagnalis, is commonly used as a model species to study how stress affects the ability to form long-term memory (LTM); however, we still have little information about how the snail senses stressful stimuli. The osphradium is an external sensory organ that demonstrates electrophysiological responses to a variety of external chemical stimuli. We examined the role, if...

Experimental infections of two South American lymnaeids (Lymnaea neotropica and L. viatrix var. ventricosa) with Paramphistomum daubneyi were carried out to determine if these snail species could sustain larval development of this digenean and, if so, to specify their potential for cercarial production. A French population of Galba truncatula infected and raised according to the same protocol s...

The freshwater snail Lymnaea stagnalis breaths bimodally either through its skin (cutaneous respiration) or via a rudimentary lung opening called the pneumostome (aerial respiration). Aerial respiratory behaviour can be operantly conditioned. Animals placed in an aquatic, hypoxic environment received a tactile stimulus to the pneumostome area every time they attempted to breathe. Over a period ...

Aquatic snails were collected at 148 sites from various wetland habitats in central Minnesota between May and September, 1988. These data were used to determine the distribution, environmental preference and parasite-intermediate host relationships of lymnaeid snails found within the study area. Lymnaeids generally preferred still water of near neutral pH with a small particle size substrate. H...

Stressor-induced memory enhancement has previously been shown to involve DNA methylation in the mollusc Lymnaea stagnalis. Specifically, injection of the DNA methylation inhibitor 5-AZA one hour before exposure to a memory-enhancing stressor obstructs memory augmentation. However, the duration of the influence of 5-AZA on this memory enhancement has not yet been examined. In this study, 2 memor...

The search for 'the how and the where' of memory formation in the brain, the engram, is still one of the unattained 'Holy Grails' of neuroscience. Over the years, various paths have been trodden in attempts to attain this goal, and while tantalizing glimpses appear now and then on the scientific horizon, the Grail still has not been grasped. One of the paths that investigators have walked is th...

The rate of ingestion of Fasciola normal metacercariae (NMc) encysted on plants by Lymnaea ollula was examined, and the infectivity of the ingested metacercariae (IMc) in the feces of the host snail to mice was studied. As a result of ingestion by snails, the metacercarial outer cyst disappeared in about 50% of IMc in feces. There was no significant difference in the liver juvenile recovery at ...