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S C Reingold

Publications and source records attributed to S C Reingold.

22 records · Page 2Linked to original sources
PubMed1980

Localization of[3H]-2-deoxyglucose in single molluscan neurones.

The glucose analogue 2-deoxyglucose (2-DG) can be used quantitatively to measure metabolic activity and is widely used qualitatively for mapping functional activity in the brain. The resolution (meaning the full width at half maximum of the grain density distribution around a line source) of the technique using [14C]-2-DG and X-ray film is limited to about 100 micrometers. Attempts have been made to improve the resolution using [3H]-2-DG (ref. 6) and cellular resolution has been achieved in the goldfish retina and with cultured mouse neurones. An anatomical technique for mapping the metabolic activity of individual neurones would be useful for studying invertebrate central nervous systems, which are relatively simple and stereotyped compared to vertebrate brains. The [3H]-2-DG technique was applied to an invertebrate in a study of the Drosophila visual system, though without cellular resolution. We present here modifications of the [3H]-2-DG technique to demonstrate localization of 2-DG in single neurones of Limax maximus, a gastropod mollusc, with a resolution of less than 1 micrometer.

Acetone↗
PubMed1980

Feeding motor programme in Limax. II. Modulation by sensory inputs in intact animals and isolated central nervous systems.

The sources of variability in feeding motor programme (FMP) of the terrestrial slug, Limax maximus, were examined in relation to: (1) changes in load on the feeding apparatus; (2) changes in concentration of attractive food stimuli; and (3) changes in satiety signalled by feedback from the gut. These sources of variability, which affect both timing of the central pattern generator for feeding and probability of occurrence of FMP, were compared in intact animals and in isolated brain preparations. The load on feeding apparatus of intact animals is altered by varying the hardness of their food. An animal will show a higher 'bite cycle' frequency on soft food as compared with hard food. In physiological preparations, weights attached to buccal muscles similarly increase load. Cycle frequency of FMP triggered by food extracts is increased when buccal muscles are unloaded compared with FMP when muscles are loaded. Increasing the chemostimulant concentration of food results in greater numbers of intact animals feeding for longer periods. Increasing the food extract concentration used to trigger FMP in physiological preparations causes similar increases in feeding duration. Intact animals use cues from gut distention to indicate satiation and terminate feeding. Inflation of the crop in physiological preparations causes an early termination of feeding activity, along with decreased FMP cycle frequency.

Animals↗
PubMed1978

Feeding motor program in Limax. I. Neuromuscular correlates and control by chemosensory input.

The feeding motor program(FMP) of the terrestrial slug Limax maximus was examined in vivo and in vitro. The feeding pattern of intact animals shows an initial increase in bite frequency followed by a plateau phase. Recordings obtained from semi-intact preparations of the lips, brain, and buccal mass established the correlation of activity in buccal ganglion nerve roots with the protraction-retraction bite cycle. A preparation of the lips, cerebral ganglia, and buccal ganglia was developed, such that, repetitive chemostimulation of the lips yields reproducible bouts of FMP. Sources of proprioceptive feedback from buccal muscles were demonstrated. The feasibility of computer scoring of the FMP is documented. The results demonstrate that aspects of in vivo feeding behavior are retained and identifiable in highly dissected, in vivo preparations.

Animals↗