Central effects of the peptides, SchistoFLRFamide and proctolin, on locust oviduct contraction.

We have developed a semi-intact preparation-consisting of an isolated oviduct with abdominal ganglia VII and VIII intact and attached-with which to characterize the effects on oviduct contraction, of peptides that are bath applied to CNS tissues. The work presented here offers a qualitative analysis of the central effects of SchistoFLRFamide and proctolin upon action potentials recorded from the oviducal nerves and upon oviduct contraction. In the process of this, we hope to demonstrate that a previously characterized putative CNS SchistoFLRFamide receptor [Peptides 23 (2002) 765] is a functional receptor.SchistoFLRFamide (10(-6)M), bath applied to abdominal ganglion VII, caused an increase in action potential frequencies recorded from the oviducal nerves, as well as an increase in the frequency of phasic contractions of the oviduct. Although the function of this response is not known, these results further support the possibility that the putative CNS SchistoFLRFamide receptors are functional receptors. Proctolin (10(-6)M), bath applied to abdominal ganglion VIII, altered the rhythmic bursting of action potentials recorded from the oviducal nerve and changed the appearance and cycle duration of neurogenic oviduct contractions.