The histochemical localization of acetycholinesterase in the thoracic dorsal root ganglia of the cat / by Wallace Witherell Ambrose.
| Author/creator | Ambrose, Wallace Witherell author. |
| Other author | McNeill, M. Evelyn, degree supervisor. |
| Other author | East Carolina University. Department of Biology. |
| Format | Theses and dissertations |
| Production | 1976. |
| Description | 78 leaves, 5 leaves of plates : illustrations ; 29 cm |
| Supplemental Content | Access via ScholarShip |
| Subjects |
| Summary | Thoracic spinal ganglia were studied morphologically and enzymatically in an attempt to correlate the position of the various sized cells within the ganglia with their degree of staining for acetylcholinesterase (AChE). This correlation could reveal a relationship between the stain uptake and sensory modality subserved by individual neurons. Dorsal root ganglia were taken from the fourth and fifth thoracic spinal levels of 6 cats ranging in age from 6 to 16 months. Frozen longitudinal and cross sections were collected serially and stained with cresyl violet for total cell counts of the ganglia. The average number found at these levels was 3500 cells. Cresyl violet studies were on ganglia from the left side of the animals. The ganglia from the right side of the animals were stained for AChE after the method of El Badawi and Schenk (1967). All the cell fragments were counted in every fourth section. Also the diameter of each fragment was recorded. The cells of each ganglia were divided into 4 groups according to the amount of enzyme demonstrated. These groups, B1 (high activity - 29%), B2 (lesser but distinct activity - 52%), B3 (about equal demonstration of enzyme and counterstain - 15%), and BL (negligible enzyme shown - 4%), were represented graphically. The study showed an inverse correlation between the size of the neurons and the amount of stain uptake. There was a size gradation within the ganglia with the smaller fragments localized toward the center and largest at the periphery. The amount of enzyme demonstration was not strictly related to size in that there was a range of sizes in each of the four color classes. It was found that over half of the fragments displayed a medium activity (B2 cells), and 96% of the cells showed some AChE activity. Ganglion cells have fibers that mediate different sensibilities (pain, touch, temperature, pressure and proprioception) depending on the size of the neuron. If enzymatic activity could be related to cell function, then a basis could be established for the study of various sensory pathways. The degree of activity could not be correlated by this study to any specific modality. There were indications that the presence of AChE and acetylcholine in dorsal root ganglion cells, where no synapses have been found, is localized in cells with small diameter (partly B1 cells), which have thinly or non-myelinated axons. The roles of acetylcholine alternative to membrane depolarization for the propagation of an action potential were discussed. |
| Local note | Joyner-"Presented to the faculty of the Department of Biology ... in partial fulfillment of the requirements for the degree Master of Arts in Biology." |
| General note | Presented to the Faculty of the Department of Biology |
| General note | Advisor: M. Evelyn McNeill |
| Dissertation note | M.A. East Carolina University |
| Bibliography note | Includes bibliographical references (leaves 36-44). |
| Genre/form | Academic theses. |
| Genre/form | Academic theses. |
| Genre/form | Thèses et écrits académiques. |
Availability
| Library | Location | Call Number | Status | Item Actions |
|---|---|---|---|---|
| Joyner | University Archives | ASK AT SPECIAL COLLECTIONS DESK | ✔ Available | Request Material |
| Electronic Resources | Access Content Online | ✔ Available |