FUNCTIONAL ROLE OF PEPTIDERGIC ANTERIOR LOBE NEURONS IN THE MALE SEXUAL
BEHAVIOR OF THE SNAIL LYMNAEA STAGNALIS.
PAMELA A.C.M. DE BOER, ANDRIES TER MAAT, ANTON W. PIENEMAN, ROGER P. CROLL,
MAKOTO KUROKAWA2 AND REN F. JANSEN..
Department of Organismal Neurobiology, Faculty of Biology, Vrije
Universiteit, De Boelelaan 1087, 1081 HV Amsterdam, The Netherlands,
Department of Physiology and Biophysics, Dalhousie University, Halifax, Nova
Scotia, Canada B3H 4H7., Department of Biology, Tokyo Metropolitan University,
Minami-Ohsawa 1-1, Hachioji-shi, Tokyo 192-03, Japan.
APStracts 4:185N, 1997.
ABSTRACT
Here we report that a morphologically defined group of peptidergic neurons in
the CNS of the hermaphroditic snail, Lymnaea stagnalis, is concerned with the
control of a very specific element of male sexual behavior. These neurons are
located in the anterior lobe of the right cerebral ganglion (rAL). Using
chronically implanted electrodes we show that the rAL neurons are selectively
active during eversion of the penis carrying structure, the preputium. The
preputium is normally contained inside the body cavity and is everted during
copulation in the male role. Electrical stimulation of the rAL neurons through
the implanted electrodes, induced eversion of the preputium in vivo. Injection
of APGWamide, a small neuropeptide which is present in all rAL neurons,
induced eversion of the preputium. Application of APGWamide to in vitro
preparations of the preputium caused relaxation of this organ. In contrast,
injection of the neuropeptide conopressin, which is colocalized with APGWamide
in 60% of the rAL neurons, did not induce any behavior associated with male
sexual activities. These results show that the neurons of the rAL can induce
an eversion of the preputium as occurs during male copulation by release of
APGWamide during a period of electrical activity.
Received 5 August 1997; accepted in final form 8 August 1997.
APS Manuscript Number J529-7.
Article publication pending J. Neurophysiol.
ISSN 1080-4757 Copyright 1997 The American Physiological Society.
Published in APStracts on 28 August 1997