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A good test for monitoring blood flow (Q(a)) must be accurate, rapid and economical in order to allow frequent easy measurements. The glucose pump test (GPT) is based on a constant glucose infusion as a dilutional indicator of Q(a).

Taste sensitivity in response to diet components was studied in larvae of the gypsy moth, Lymantria dispar, by means of electro-physiological and behavioural approaches. Dose-response rela tionships were studied for NaCl, sucrose, and nicotine solutions with the aim of better characterizing chemoreceptor cells involved in gustation. Results showed that medial sensilla styloconica in the galea are specifically sensible to deterrent substances like salt and nicotine; instead, lateral sensilla showed a marked sensitivity to sugars. Morphological and electrophysiological data on the possi ble role of the sensilla basiconica of the maxillary palps are also reported. On the basis of the results obtained, it is proposed that taste chemoreceptor cells in the gypsy moth should be catego rized as phagostimulatory or deterrent on the basis of their behav ioural effects, rather than of their responding to specific stimuli.

The integration of sensory information with adequate motor outputs is critical for animal survival. Here, we present an innovative technique based on a non-invasive closed-circuit device consisting of a perfusion/stimulation chamber chronically applied on a single leg of the crayfish Procambarus clarkii. Using this technique, we focally stimulated the leg inside the chamber and studied the leg-dependent sensory–motor integration involving other sensory appendages, such as antennules and maxillipeds, which remain unstimulated outside the chamber. Results show that the stimulation of a single leg with chemicals, such as disaccharides, is sufficient to trigger a complex search behaviour involving locomotion coupled with the reflex activation of antennules and maxillipeds. This technique can be easily adapted to other decapods and/or other sensory appendages. Thus, it has opened possibilities for studying sensory–motor integration evoked by leg stimulation in whole aquatic animals under natural conditions to complement, with a direct approach, current ablation or silencing techniques.

AbstractThe gypsy moth Lymantria dispar,like many other forest defoliator species, exhibits periodic population outbreak dynamics, whose variability in different years and in different places can be attributed to different microclimatic parameters. This study was focused on the correlation between climatic variations in two different localities of Sardinia over a three‐year period and on changes in sensitivity of the male antennal olfactory receptors. Our electrophysiological results show that olfactory EAG responses to the sex pheromone of the antennae are inversely correlated with rainfall during gypsy moth larval development. On the other hand, male antennal sensitivity and ambient temperature were not correlated, possibly due to the fact that no significant climatic variations were detected in the period examined. Our findings, especially for rainfall, are in good agreement with data in the literature concerning the effects of weather on gypsy moth population dynamics.

Parkinson’s disease (PD) is one of the most common neurodegenerative diseases characterized by the clinical triad: tremor, akinesia, and rigidity. Several studies have suggested that PD patients show disturbances in olfaction as one of the earliest, nonspecific nonmotor symptoms of disease onset. We sought to use the fruit fly Drosophila melanogaster as a model organism to explore olfactory function in LRRK loss-of-function mutants, which was previously demonstrated to be a useful model for PD. Surprisingly, our results showed that the LRRK mutant, compared to the wild flies, presents a dramatic increase in the amplitude of the electroantennogram responses and this is coupled with a higher number of olfactory sensilla. In spite of the above reported results, the behavioural response to olfactory stimuli in mutant flies is impaired compared to that obtained in wild type flies. Thus, behaviour modifications and morphofunctional changes in the olfaction of LRRK loss-of-function mutants might be used as an index to explore the progression of parkinsonism in this specific model, also with the aim of studying and developing new treatments.