Hans-Rudolf Güttinger

Immunocytochemical localization of estrogen-binding neurons in the songbird brain

This study used monoclonal antibodies against estrogen receptor for the identification and localization of estrogen-binding cells in the avian brain. The distribution of estrogen-binding neurons in the songbird brain conformed to the general vertebrate pattern with highest labelling in hypothalamus and preoptic area. For the first time, estrogen-binding neurons were found in the song control system: these neurons might provide a substrate for the direct action of estrogen on the song system.

Korrelationen zwischen der sexualdimorphen Gehirndifferenzierung und der Verhaltensausprägung bei Prachtfinken (Estrildidae)

Sex dimorphism in song controlling brain areas is studied inUraeginthus bengalus, an Estrildid species, in which male and female sing regularly. Compared to Zebra finches the vocal brain centers such as RA, HVc and Area X are well developed in females ofUraeginthus.

Testosteronkonzentrationen und Fortpflanzungsverhalten beim Japanischen Mövchen (Lonchura striata var.domestica, Estrildidae)

No relation of singing, courtship and copulation activity with testosterone titers were found. Song activity was high with individual titers below 1200 pg/ml. Even copulations occurred during stages of the reproductive cycle with basal testosterone levels.

Die Beeinflussung des Gesangs- und Brutverhaltens von Kanarienweibchen durch Steroidmanipulationen

To assess the organizing effects of steroids on singing and breeding behaviour of female canaries, 11 females were treated with estradiol and testosterone until day 300. Unlike controls, treated females sing regularly. However, 30 days after the termination of steroid therapy, they exhibit normal female behaviour towards males. Lowered reproductive activity was only detectable in those females which where treated with testosterone during very early development (day 30–60).

Längerfristige Schwankungen in den Plasmaspiegeln von Testosteron und Dihydrotestosteron unter konstanter Testosterongabe beim Kanarienvogel (Serinus canaria)

To assess the action of testosterone on the ontogenetic song development of canaries, silastic tubes containing testosterone propionate were implanted in 10 males at day 60. The implants were renewed at two week intervals until day 116. During the exogenous testosterone application the following time-related changes in the plasma titers were measured. The highest peaks of testosterone occurred 20 days after the first testosterone implantation. Between days 20 and 50 this concentration decreased drastically whereas DHT-concentration gradually reached a maximum. We assume that exogenous testosterone induces higher metabolic activity by converting the testosterone to DHT.

„Normale“ Steroidmuster bei jung kastrierten Kanarienvögeln

To elucidate the organizing effects of sex steroids on the song development of male canaries, 5 males were castrated at the age of 20 days, plasma titers of testosterone and estradiol were studied up to day 200. These gonad-ectomized males developed high peaks of estradiol, similar to those of normal males. Mit Unterstützung der Deutschen Forschungsgemeinschaft „Verhaltensontogenese“ (GU 148/8).