Effect of incubation temperature and androgens on dopaminergic activity in the leopard gecko, Eublepharis macularius.
Male leopard geckos that hatch from eggs incubated at a female-biased temperature (Tf) behave differently when compared with males hatching at a temperature which produces a male-biased sex ratio (Tm). We investigated the effect of incubation temperature and androgen implantation on aspects of the dopaminergic system of Tf and Tm males. Our data suggest that more dopamine (DA) is stored in the nucleus accumbens of naive Tf males compared with naïve Tm males when they encounter a receptive female conspecific across a barrier. No difference was measured in the preoptic area and the ventral tegmental area (VTA). This difference in intracellular DA levels in a motivation-related brain nucleus might be correlated with differences in sociosexual behavior observed between the two morphs. There were no differences in tyrosine hydroxylase (TH) expressing cell numbers in the VTA of cholesterol (CH)-implanted naive castrated Tf and Tm males. Only Tf males implanted with testosterone had significantly higher TH immunopositive cell numbers in the VTA compared with CH- and dihydrotestosterone-implanted Tf males. These data indicate that both the embryonic environment as well as the circulating hormonal milieu can modulate neurochemistry, which might in turn be a basis for individual variation in behavior.
Dias
Brian George
BG
Institute for Neuroscience, University of Texas at Austin, Austin, Texas, USA.
Ataya
Ramona Sousan
RS
Rushworth
David
D
Zhao
Jun
J
Crews
David
D
D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000728:Androgens / Q000494:pharmacology*; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D002452:Cell Count; D002784:Cholesterol / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D013196:Dihydrotestosterone / Q000494:pharmacology; D004298:Dopamine / Q000378:metabolism*; D005260:Female; D008116:Lizards / Q000502:physiology*; D008297:Male; D009474:Neurons / Q000378:metabolism; D009714:Nucleus Accumbens / Q000187:drug effects / Q000378:metabolism; D011301:Preoptic Area / Q000187:drug effects / Q000378:metabolism; D013696:Temperature; D013739:Testosterone / Q000494:pharmacology; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism; D017557:Ventral Tegmental Area / Q000166:cytology / Q000378:metabolism
D000728:Androgens; D013196:Dihydrotestosterone; D015102:3,4-Dihydroxyphenylacetic Acid; D013739:Testosterone; D002784:Cholesterol; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine