nNOSI and 6OHDA Treatments Illicit Different Motor Deficiency Symptoms in Embryonic Zebrafish Presented by: Connor Culley, Derek Emerson, and Chris Baker BI-420W-01 Seminar Research Presentation Biology Department Virginia Military Institute

Introduction Estrogen’s (E2) is a steroidal signaling hormone Function: neuron protection . Upstream regulator of nitric oxide synthesis (NOS). Dopamine (DA) is a neurotransmitter involved in motor function 6OHDA is a neurotoxin that causes dysfunction in DA producing neurons in zebrafish (Parng et al., 2007) nNOSI is an enzyme responsible for the inhibition of the synthesis of nitric oxide (NO) in nervous tissue NO is a gaseous signaling molecule involved in motor control (Lorenc-Koci and Czarnecka, 2013)

Hypothesis If embryonic zebrafish are exposed to either nNOSI or 6OHDA, then they will produce the same listless PD-like symptoms. E2 co-treatment will rescue the fish from these neurological symptoms

Zebrafish Model Why Zebrafish? Optically transparent CNS and organs. Known genome. Easy maintenance of survival. Readily absorb chemicals. Small size conducive to larger sample size. Simple, cheap, rapidly reproducible biological model. An established model for the study of motor deficits with PD-like symptoms (Flinn et al., 2008)

Materials 6-day old Casper zebrafish Dissecting microscope Pipets and probes 6-OHDA (500 µM), nNOSI (50 µM) , ERS, E2 (100 µM) Sterilized 6-well plates Incubator

Methods Exp #1: nNOSI (10, 25, 50 µM) dose response study Exps #2 – 6: treatments: ERS nNOSI 6-OHDA E2 + nNOSI E2 + 6OHDA

Methods Motor behavior analyses (% of population demonstrating deficits 24 hrs after treatment) Listless – no spontaneous swimming, laying on side, now swimming response to probe Dyskinesia – rapid sporadic, twitchy/spastic swimming Data analysis Data were analyzed for significant differences either by a z-test for two population proportions or for multiple proportions using a chi-square contingency table test followed by a Marascuilo's post hoc analysis

Directions: insert error bars (±SEM); do stats for multiple proportions; write figure legend Results Figure 1.

Results Directions: cull out just 24 hor data & add nNOSI results; insert error bars (±SEM); do stats for multiple proportions; write figure legend Figure 2.

Conclusions Directions: finish, 2-3 points

Future Studies

References Flinn et al., 2008 Lorenc-Koci and Czarnecka, 2013 Parng et al., 2007 Directions: complete citations

Acknowledgements