| Description |
The bluehead wrasse, Thalassoma bifasciatum, is a protogynous fish that undergoes a socially controlled sex change and is often used as a model for studying neuronal plasticity. Much of the underlying neuronal circuit that leads to the sex change is unknown. Immunohistochemistry provides valuable insights into what regions could be responsible. The c-Fos protein is associated with high neuroplasticity. The nucleus of the tenth cranial nerve (Xn) is associated with parasympathetic regulation and was expected to exhibit higher c-Fos activity in courting fish than noncourting fish. The posterior tuberal nucleus (PTN), the nucleus preopticus parvocellularis (NPO), and two subnuclei of the ventral telencephalon, the area ventralis telencephali, pars supracommisuralis (Vs) and the area ventralis telencephali, pars ventralis (Vv) are associated with control of sexual behaviors in fish and were expected to exhibit higher c-Fos activity in courting than noncourting and unprimed fish. Our results indicate no significant difference. However, as will be shown in another honor's thesis from this lab, we have found that the interpeduncular nucleus, ventrolateral region of the thalamus, and the red nucleus are all less active in the brains of initial phase (IP) females performing male-typical courtship behaviors than noncourting IP females. Furthermore, through glutamate stimulation of immobilized fish in four different regions of the brain, we were able to elicit color changes associated with courtship. |
