Chemoreception in the mud snail, Nassarius obsoletus. II. Identification of stimulatory substances.

TLDR: In this article, a study was made of the compounds in shrimp extracts which induce the proboscis search reaction in Nassarius obsoletus and the results showed that the compounds were as follows: alanine, asparagine, aspartic acid, betaine, glutamic acid, glycine, histidine, homarine, inosine, isoleucine and leucine.

Abstract: 1. A study was made of the compounds in shrimp extracts which induce the proboscis search reaction in Nassarius obsoletus.2. Compounds identified in shrimp extracts were as follows: alanine, asparagine, aspartic acid, betaine, glutamic acid, glycine, histidine, homarine, inosine, isoleucine, leucine, lactic acid, lysine, methionine, phenlyalanine, proline, serine, taurine, threonine, trimethylamine oxide, tryptophan, tyrosine, urea, and valine. Carnitine was tentatively identified. The amino acids and lactic acid were determined quantitatively; betaine was determined semi-quantitatively.3. Glycine (ca. 10-3 M) and lactate (ca. 5x 10-4 M) were the only compounds identified in the extracts which possessed marked stimulatory capacities when tested individually; betaine (ca. 10-3 M) was mildly stimulatory. However, quantitative analyses of these compounds in shrimp extracts showed that they were present in insufficient concentrations to account for the responses observed with the dilutions of extract which we...