IAC-USNC Methods in Neuroscience- Manduca Sexta- MAIN PAGE


All the photos here were taken at the Marine Biological Laboratory in Woods Hole, Massachusetts during the summer 2001 Neural Systems and Behavior (NS&B) course. Many thanks to the course instructors and students who made these pages possible.
	MANDUCA TEAM Stephanie Palmer (student at UCSF) Shari Hertzberg (student at U. Penn) NS&B Course Instructors on Manduca: JANIS C. WEEKS, Professor and Head, Department of Biology, Univ of Oregon, RICHARD B. LEVINE, Professor, Departments of Neurobiology and Physiology, Arizona Research Laboratories

Ecdysis Larvae Dissection 1 Dissection 2
Recording 1 Recording 2 Recording 3 Manduca Home

OVERVIEW

Manduca is a relatively simple nervous system in which it is possible to identify and follow individual neurons through precise developmental stages and in which specific changes in neuronal structure, function and synaptic connectivity can be related to changes in behavior. An interesting advantage of this preparation is that by observing behavior one can gain some understanding of nervous system function.

The Manduca preparation combines the relative simplicity of an insect nervous system with a dramatic, postembryonic reorganization of neuronal circuits and behavior during metamorphosis, under hormonal control. The Manduca preparation is often used to explore key concepts of developmental neurobiology, neuronal plasticity, and endocrine regulation of the nervous system at the cellular level.

In the Manduca preparation intra- and extracellular recordings can be made from identified neurons in reduced preparations from the different life stages. Neurons can be stained using cobalt or fluorescent dyes. These techniques together can be used to explore how identified neurons and their synaptic connections are modified to produce the behavioral changes associated with metamorphosis.

Postembryonic plasticity of the Manduca nervous system and behavior is produced by developmental mechanisms, such as neurogenesis, dendritic growth, programmed cell death and synaptic rearrangments. In addition, many of the developmental changes that accompany insect metamorphosis are regulated by steroid hormones (which act through genomic actions similar to those produced by vertebrate steroids). Using the Manduca preparation it is possible to observe first-hand how hormones exert powerful effects on behavior via changes in neuronal structure and function. The more rapid modulation of behavior by peptide hormones can also be observed by examining the effects of eclosion hormone, ecdysis triggering hormone and other neuropeptides on neural circuits and behavior.