Meeting Abstract

P2.85  Thursday, Jan. 5  THE RESPONSE OF THE EARTHWORM CROP/GIZZARD TO MEMBERS OF THE OXYTOCIN/VASOPRESSIN FAMILY OF PEPTIDES BONE, N. B.*; KRAJNIAK, K. G.; Southen IL Univ. Edwardsville; Southern IL Univ. Edwardsville nbone@siue.edu

Members of the Oxytocin/Vasopressin family of peptides are present in both vertebrates and invertebrates. While oxytocin and vasopressin are found in vertebrates, annetocin is found exclusively in annelids. Many of these peptides modulate the motility of smooth muscle. Several experiments have been performed on several species of Annelids regarding the effects of annetocin, oxytocin, and vasopressin. However, the effects of these peptides have yet to be determined in the earthworm Lumbricus terrestris. In this study we used isolated the crop-gizzard of L. terrestris to measure the effects of oxytocin. The crop-gizzard was removed from the animal, placed in a tissue bath, and connected to a force transducer. The responses to increasing concentrations of peptide were recording using a computer with an Iworx converter and Labscribe 2. Preliminary findings show that the oxytocin increased contraction rate with a threshold of 10^-8 M, and amplitude with a threshold between 10^-8 and 10^-7 M. Other peptides in the oxytocin/vasopressin family are also being investigated for their effects on the crop/gizzard of the earthworm.