Neurophysiology of adult male Schistosoma mansoni

Abstract

From the studies on the neurophysiology of schistosomes it appears that in spite of the unique hexilaminar arrangement of the tegument's outer membrane, it has biophysical properties not markedly different from those of a variety of other multi-dimensional syncytia. The close electrical coupling of the muscle and tegument must be taken into account when one attempts to define sites and modes of action of drugs which affect motor activity. Agents which disrupt muscle function in the schistosome may exert their action indirectly by way of an effect on the tegumental membrane. The syncytial nature of the musculature and the possibility that longitudinal contraction waves are myogenic suggests that neurotransmitters may simply function as modulators of muscle activity as is the case for many vertebrate visceral muscles. External recordings indicate the presence of a variety of electrically active tissues within the schistosomes. There is no clear correlation of this activity with longitudinal muscle activity or with active membrane responses in this muscle. From this it would appear the bulk of this activity may have its origins in tissues other than the longitudinal muscle such as other muscle groups, nerve trunks, or the peripheral nerve net.