(Received for publication, August 1, 1951)

Muscle and other tissues of marine invertebrates are very dilute with

respect to inorganic ions, but are nevertheless in osmotic equilibrium with

the blood, in which ionic concentrations are nearly the same as in sea

water (1). It has been postulated, therefore, that these tissues contain

relatively high concentrations of small organic molecules (l), and it is of

...interest in this connection that considerable

acids and trigonelline. Both seedlings grown in the laboratory or purchased in

a supermarket were studied by HPLC. Samples from both origins contained

uracil-alanine derivative (isowillardiine) in substantial amount. Some of these

EFFECTS OF THE NON-PROTEIN AMINO ACIDS

BY ANN E. KAMMER

D. L. DAHLMAN

AND GERALD A. ROSENTHAL

Injection of L-canavanine, a naturally occurring arginine analogue, and of

its metabolic derivative, L-canaline, induced almost continuous motor

flew normally, but after a time interval that depended both on the amino

acid and on the dose (1-45/miol/g fresh weight) the moths became disorientated

and muscle activity was less patterned. Canaline produced its

initial effects 12-30 min after injection, whereas activity in response to

by an arginase-mediated hydrolytic cleavage) is probably the biologically

active factor.

Canaline did not affect axonal conduction of action potentials nor the

activity of mechanoreceptors on the forewing. Canaline (22/miol/g fresh

weight) prolonged the postsynaptic potential of flight muscle fibres, but

after 20-40 min. the electrical activity of muscle fibres was normal