Quantitative Determination of Myotropic Neuropeptide in the Nervous System of the Cockroach Leucophaea Maderae: Distribution and Release of Leucokinins

Content Provider	Semantic Scholar
Author	Muren, Nassel. J. Eric Lundquist, Christine Dick, Richard
Copyright Year	1993
Abstract	Being interested in the distribution and function of insect myotropic peptides, we developed a sensitive radioimmunoassay (RIA) using an antiserum directed against the cockroach neuropeptide leucokinin I. The levels of leucokinin immunoreactivity were measured in extracts of different portions of the nervous system, in the retrocerebral complex and in the hemolymph of the cockroach Leucophaea maderae. The brain contains about 1.9 pmol of immunoreactive material while the ganglia of the ventral nerve cord each contain less than 10 % of this amount. Large amounts of leucokinin immunoreactivity (6.6 pmol per tissue) were found in the corpora cardiaca-corpora allata (CC-CA) complex and in the hemolymph the titer was in the nanomolar range. When levels of leucokinins were compared in male and female cockroaches, no differences could be detected in any of the sample tissues. A calcium-dependent release of leucokinin-immunoreactive material could be induced from isolated CC-CA complexes by high-potassium depolarization. The amount of released immunoreactivity, as measured in the bathing saline by RIA, was about 2 % of the extractable leucokinin immunoreactivity in the CC-CA complex. In Leucophaea maderae, the leucokinins apparently act both as neuroactive substances in the central nervous system and as neurohormones released into the circulation.
Starting Page	289
Ending Page	300
Page Count	12
File Format	PDF HTM / HTML
Volume Number	179
Alternate Webpage(s)	http://jeb.biologists.org/content/jexbio/179/1/289.full.pdf
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article