Immunocytochemical localization of androgen receptors in the male songbird and quail brain

Abstract

The distribution of androgen receptors was studied in the brain of the Japanese quail (Coturnix japonica), the zebra finch (Taeniopygia guttata), and the canary (Serinus canaria) by immunocytochemistry with a polyclonal antibody (AR32) raised in rabbit against a synthetic peptide corresponding to a sequence located at the N-terminus of the androgen receptor molecule. In quail, androgen receptor-immunoreactive cells were observed in the nucleus intercollicularis and in various nuclei of the preoptic-hypothalamic complex, namely, the nucleus preopticus medialis, the ventral part of the nucleus anterior medialis hypothalami, the nucleus paraventricularis magnocellularis, the nucleus ventromedialis hypothalami, and the tuberal hypothalamus. In the two songbird species, labeled cells were also observed in various nuclei in the preoptic-hypothalamic region, in the nucleus taeniae, and in the nucleus intercollicularis. Additional androgen receptor-immunoreactive cells were present in the androgen-sensitive telencephalic nuclei that are part of the song control system. These immunoreactive cells filled and outlined the boundaries of the hyperstriatum ventrale, pars caudalis, nucleus magnocellularis neostriatalis anterioris (both in the lateral and medial subdivisions), and nucleus robustus archistriatalis. The immunoreactive material was primarily present in cell nuclei but a low level of immunoreactivity was also clearly detected in cytoplasm in some brain areas. These studies demonstrate, for the first time, that androgen receptors can be detected by immunocytochemistry in the avian brain and the results are in general agreement with the binding data obtained by autoradiography with tritiated dihydrotestosterone. Immunocytochemical methods offer several advantages over autoradiography and their use for the study of the androgen receptor will greatly facilitate the analysis of steroid-sensitive systems in the avian brain.

Examining a pathway for hormone mediated maternal effects – Yolk testosterone affects androgen receptor expression and endogenous testosterone production in young chicks (Gallus gallus domesticus)

“…Further, the overall distribution of AR mRNA in the chicken brain was similar to the distribution of AR protein in the closely related Japanese quail [6,52] and similar to the distribution of AR mRNA of songbirds, with exception of areas present in the forebrain of songbirds [32]. Even brain regions that are rarely reported as expressing AR mRNA such as the cerebellum [32] were detected (see also Fig.…”

The Role of Auditory Experience in the Formation of Neural Circuits Underlying Vocal Learning in Zebra Finches

“…Alternatively, the absence of normal auditory input may indirectly affect the development of topographic organization in the lMAN core 3 RA circuit. Deafening or isolating juvenile birds delays the increase in levels of testosterone that normally occurs by 35 d, and lower T levels could in turn affect topographic organization within the lMAN core 3 RA circuit during this period (Pröve, 1983;AdkinsRegan et al, 1990;Korsia and Bottjer, 1991;Balthazart et al, 1992;Whaling et al, 1995;White et al, 1999;Livingston et al, 2000;cf. Bottjer and Johnson, 1997;Wang et al, 1999).…”

Revised nomenclature for avian telencephalon and some related brainstem nuclei

“…Of note, amygdaloid features of the nucleus taeniae have been shown by recent neurochemical, connectional, developmental. and functional studies (Balthazart et al, 1992(Balthazart et al, , 1998Cheng et al, 1999;Foidart et al, 1999;Lanuza et al, 2000;Cobos et al, 2001b, Absil et al, 2002Roberts et al, 2002). For this reason, the Forum recommended that the nucleus taeniae be renamed the nucleus taeniae of the amygdala (Table 5, Fig.…”