Meeting Abstract

P3.197  Monday, Jan. 6 15:30  Effect of Sex Steroid Hormones on Spinophilin Production in the Male Checkered Garter Snake Forebrain SCHMESKI, S.M.*; KLIMA, B.M.; MONZON, R.; KROHMER, R.W.; Saint Xavier University, Chicago, IL; Saint Xavier University, Chicago, IL; Saint Xavier University, Chicago, IL; Saint Xavier University, Chicago, IL stephsxudance@gmail.com

Dendritic protrusions, known as dendritic spines, receive much of the incoming excitatory signals from associated contacts with surrounding neurons. Since the numbers of actual dendritic spines/synapses are immense, determining changes in spinophilin, a specific scaffold, cytoskeletal protein that is vital for the proliferation of novel spines, offers a method for quantifying regional changes. In a previous study, male red-sided garter snakes (Thamnophis sirtalis parietalis) exhibited neuronal plasticity in response to sex steroid hormones with dendritic spine formation greater under the influence of estrogen compared to testosterone. This study also revealed that red-sided garter snakes exhibited a seasonal/brain-region response in the concentration of dendritic spinophilin. In the current study we examined the role of sex steroid hormones on spinophilin production in the brain of male checkered garter snakes (Thamnophis marcianus). We hypothesize that, in the male checkered garter snake, like the red-sided garter snake, estrogens have a greater effect on the regulation of neuronal plasticity in regions critical for the control of reproductive behavior. Using unbiased western immunoblots, we examined regional variations in the concentration of dendritic spinophilin in the brains of male checkered garter snakes that had been implanted with either estrogen or testosterone. Our data indicate spinophilin levels were greater in animals implanted with estrogen compared to testosterone.