9514135 Westfall Sea anemones are marine invertebrates that belong to the most primitive group of animals with a nervous system. Studies of these animals reveal nerve-cell function at its most elemental. Research on the relatively simple nervous systems of these animals can reveal the nature of neurotransmitter and neurohormone prototypes early on the evolutionary scale. Earlier studies by Dr. Westfall, and supported by the NSF, suggest that even these primitive nervous systems include both excitatory and inhibitory interconnections. Research under this award includes ultrastructural studies to describe in detail the synaptic contacts between sensory cells, ganglion cells, and the harpoon-like stinging capsules (nematocysts). These anatomical studies with the electron microscope are complemented by additional studies that employ immunohistochemistry to identify and localize neurohormones in the sea anemones. These studies provide a unique look at the first-evolved nervous systems, which will help inform all of biology about the evolution of higher animals.
