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bioRxiv · 10.1101/2022.12.08.519640

Neuron- and microglial specific immunoexpression in steroid-independent male sexual behaviour in castrated B6D2F1 male mice

Chiang, V. S.-C.·Lipkin, S.·McCusker, C. D.·Park, J. H.
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Abstract

Sexual behaviour is necessary for procreation for several species and is traditionally viewed to be regulated by sex steroid hormones. However, several species exhibit steroid-independent sexual behaviour, and its molecular understanding is only beginning to be uncovered. The main goal of our experiment was to provide new insight into cell-specific roles that both neuronal and non-neuronal cells may play in steroid-independent male sexual behaviour. Forty B6D2F1 hybrid male mice underwent orchidectomy and were tested for reinstatement of steroid-independent male sexual behaviour after an extended period of social isolation caused by the COVID-19-mandated laboratory shutdown. After 62 weeks post-orchidectomy, 20.59% demonstrated reinstatement of steroid-independent male sexual behaviour (identified as steroid-independent persistent maters), while 23.53% of the males did not display steroid-independent male sexual behaviour (identified as steroid-independent non-maters). Using flow cytometry, we compared the preoptic area immunoexpression in NeuN+ neurons and Iba1+ microglia between steroid-independent persistent maters and steroid-independent non-maters (N = 5-6 per group). We found neuronal immunoexpression up-regulated for amyloid precursor protein and androgen receptor, as well as down-regulated for glucocorticoid receptor in steroid-independent persistent maters compared to steroid-independent non-maters. In conjunction, microglial immunoexpression of amyloid precursor protein was up-regulated in steroid-independent persistent maters compared to steroid-independent non-maters. These data suggest there are cell-specific immunoexpression differences, including the role of non-neuronal cells in steroid-independent male sexual behaviour.

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Chiang, V. S.-C., Lipkin, S., McCusker, C. D., Park, J. H.. 2022-12-08. Neuron- and microglial specific immunoexpression in steroid-independent male sexual behaviour in castrated B6D2F1 male mice. https://doi.org/10.1101/2022.12.08.519640

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