QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online July 26, 2004
Journal of Experimental Biology 207, 3089-3098 (2004)
Published by The Company of Biologists 2004
doi: 10.1242/jeb.01145

This Article Summary Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Gaston, M. R. Articles by Tublitz, N. J. Search for Related Content PubMed PubMed Citation Articles by Gaston, M. R. Articles by Tublitz, N. J.

Peripheral innervation patterns and central distribution of fin chromatophore motoneurons in the cuttlefish Sepia officinalis

Michelle R. Gaston^* and Nathan J. Tublitz

Institute of Neuroscience, 1254 University of Oregon, Eugene, OR 97403-1254, USA

View larger version (75K): [in a new window]   Fig. 1. Branching pattern of fin nerve in Sepia officinalis. (A) Drawing illustrating the bilateral branching pattern from a 17.5 cm mantle length male. Primary anterior branches are colored red on the upper half of the diagram and are labeled from anterior to posterior on the lower half of the diagram (A1-A4, bold; colored orange, yellow, green, blue). Primary posterior branches are labeled from posterior to anterior on the upper half of the diagram (P1-P4, bold; colored purple). Subsequent branches (2°, 3°, 4°) are indicated by normal, italic and underlined text, respectively. (B) Photomicrograph showing the branching pattern on the left side of a 10.8 cm mantle length male. Several anterior branches (a), posterior branches (p), and blood vessels (bv) are labeled. Inset is a drawing of the nerves in the photograph; blood vessels are colored black. Scale bar, 2 mm.

View larger version (98K): [in a new window]   Fig. 2. Fin nerve stimulation in Sepia officinalis. Still video frames from stimulation of a primary fin nerve branch in one animal, A1 (A1, A2), and one of its secondary branches, A1a (B1, B2), in a different animal. A1 and B1 show the fin immediately prior to stimulation when chromatophores are retracted; A2 and B2 show fin chromatophores expanded during stimulation. Chromatophores expanded in B2 are a subset of those expanded in A2. Although yellow, orange and dark brown chromatophores were all activated, only the latter two colors are visible in the still frames. Scale bars, 5 mm (A1,A2); 6 mm (B1,B2).

View larger version (33K): [in a new window]   Fig. 3. Topographic innervation of the fin in Sepia officinalis. Topographic innervation among 1° anterior and posterior fin nerve branches (A) and 2° anterior nerve branches (B) is shown. Overlapping regions of chromatophore activity for neighboring nerves were observed at both the 1° and 2° nerve levels. Colored points on nerve branches represent stimulation locations, while corresponding colored lines parallel to fin illustrate the regions of chromatophore activity. Insets highlight the locations (red boxes) of the enlarged drawings.

View larger version (39K): [in a new window]   Fig. 4. Retrograde labeling of fin nerve branches in Sepia officinalis. (A) Drawing of fin nerve indicating dye-injected branches. One injection per branch, each in a different animal. (B) Sagittal section of a cephalopod brain (adapted from Novicki et al., 1990) with major areas labelled: supraesophageal mass (SupraEM), posterior subesophageal mass (PSEM), middle subesophageal mass (MSEM), anterior subesophageal mass [ASEM; composed of the brachial lobe (BRL) in Sepia]. Dye-labeled cells were located in the PSEM and BRL. (C) Diagram showing position of the stellate ganglion (SG), where a few cells were labeled. SG is in the dorsal mantle, and fin nerve branches (e.g. A1 and A2) are dorsal to the SG. Inset in A highlights the location (box) of the enlarged drawings in A (horizontal) and in C (vertical). A, anterior; P, posterior; D, dorsal.

View larger version (134K): [in a new window]   Fig. 5. Dye-labeled cells in Sepia officinalis. Lateral (A) and medial (B) sagittal sections of the posterior subesophageal mass (PSEM) showing distribution of labeled cells across PSEM lobes (posterior chromatophore lobe, PCL; fin lobe, FL; palliovisceral lobe, PVL; magnocellular lobe, MCL, covered by inset in A; posterior posterior chromatophore lobe, PPCL, not present in sections shown but approximate location is indicated by an asterisk in A). Arrows point to individual labeled cells. (C,D) Higher magnification of two separate clusters of labeled cells. Insets highlight locations (red boxes) where photographs were taken. Insets A and B show an outline of an entire cephalopod brain; insets C and D are outlines of the PSEM only. A, anterior; P, posterior. Scale bars, 500 µm (A,B); 50 µm (C,D).

View larger version (17K): [in a new window]   Fig. 6. Cell count totals in Sepia officinalis. Total number of cells labeled in the brain and stellate ganglion (SG; A) and the percent of labeled cells located in and outside of the posterior subesophageal mass (PSEM; B) from each of three dye-injected fin nerve branches (A1, P1, A1a) are shown. For branch P1, only cells in the brain were counted, as the SG was not sectioned; thus, cells outside of the PSEM are from the brachial lobe (BRL) only.

View larger version (16K): [in a new window]   Fig. 7. Distribution of labeled cells in Sepia officinalis. Percent of labeled cells located throughout the nervous system for three dye-injected fin nerve branches (A1, P1, A1a) is shown. N/A, data not available; PPCL, posterior posterior chromatophore lobe; PCL, posterior chromatophore lobe; FL, fin lobe; PVL, palliovisceral lobe; MCL, magnocellular lobe; BRL, brachial lobe; SG, stellate ganglion.