The modulatory effects of serotonin, neuropeptide F1 and proctolin on the receptor muscles of the lobster abdominal stretch receptor and their exoskeletal muscle homologues

The modulatory effects of serotonin, neuropeptide F1 and proctolin on the receptor muscles of the lobster abdominal stretch receptor and their exoskeletal muscle homologues

ABSTRACT The muscle receptor organ (MRO) of the lobster is a complex proprioceptive system lying in parallel with the axial extensor musculature. Two peripherally located sensory neurones extend stretch-sensitive dendrites into individual receptor muscle strands one tonic (RM1) and one phasic (RM2)....

Full description

Saved in:
Bibliographic Details
Published in:Journal of experimental biology Vol. 174; no. 1; pp. 363 - 374
Main Authors: PASZTOR, V. M, GOLAS, L. B
Format: Journal Article
Language:English
Published: Cambridge Company of Biologists 1993
The Company of Biologists Ltd
Subjects:
Biochemistry. Physiology. Immunology
Biological and medical sciences
Crustacea
Fundamental and applied biological sciences. Psychology
Hormones
Invertebrates
Marine biology
Muscular system
Physiology. Development
Shellfish
Proctolin
Serotonin
Sensory receptor
Striated muscle
Neuropeptide
Macrura
Abdomen
Crustacea
Marine environment
Homarus americanus
Synapse
Arthropoda
Neuromediator
Stretch receptor
Decapoda
Invertebrata
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:ABSTRACT The muscle receptor organ (MRO) of the lobster is a complex proprioceptive system lying in parallel with the axial extensor musculature. Two peripherally located sensory neurones extend stretch-sensitive dendrites into individual receptor muscle strands one tonic (RM1) and one phasic (RM2). Previous studies have shown that the sensitivity of the sensory neurones to passive stretch could be enhanced by serotonin and proctolin. Here we show that the receptor muscles and their exoskeletal muscle homologues are also responsive to serotonin, proctolin and, in addition, to neuropeptide F1 (TNRNFLRF-NH2). Two measures of motor performance were enhanced by all three neurohormones: EJP amplitude and nerve-evoked tension development. Serotonin was the most effective modulator of both tonic and phasic muscles. F1 had powerful effects on the phasic extensor muscle. A low incidence of tonic muscle fibres with synapses responding to the neurohormones suggests that there are distinct populations of synapses: those sensitive to specific modulators and others that are insensitive. These findings, taken together with the enhancing effects of modulation on the primary sensory afferents, suggest that circulating neurohormones may act at multiple loci in the MRO system in a concerted and hormone-specific manner to alter the flow of proprioceptive feedback.
ISSN:0022-0949
1477-9145
DOI:10.1242/jeb.174.1.363