Modification of synapses in androgen-sensitive muscle. I. Hormonal regulation of acetylcholine receptor number in the songbird syrinx

Bleisch, William V.; Luine, V. N.; Nottebohm, Fernando

doi:10.1523/jneurosci.04-03-00786.1984

Cited by 56 publications

(31 citation statements)

References 20 publications

(27 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Testosterone influences the physiology and structure of some neurons (e.g., refs. 42 and 43), and these effects have been shown in the song system (44)(45)(46)(47). If testosterone plays a role in the survival of neurons born in adult males, then it seems to affect similarly those HVC cells that project to RA and others, perhaps interneurons, that do not project to RA.…”

Section: Discussionmentioning

confidence: 90%

The life span of new neurons in a song control nucleus of the adult canary brain depends on time of year when these cells are born.

Nottebohm

O'loughlin²,

Gould³

et al. 1994

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

View full text Add to dashboard Cite

The number of high vocal center (HVC) neurons labeled in adult male caries by systemic Injections of [3H]thymidine depended on season and survival time. This was true for HVC neurons projecting to the robust nucleus of the archistriatum and for other HVC neurons that could not be retrogradely filled from the robust nucleus of the archistriatum. Birds Injected in October and killed 40 days later had twice as many labeled HVC neurons as birds injected in May and killed 40 days later. However, this difference became much larger (5 times) when the birds were allowed to survive for 4 months. Whereas more than half of the spring-born neurons disappeared between 40 days and 4 months, there was no reduction in the number of fall-born neurons present at the 4-month survival point. We infer that seasonal variables affect the life span of HVC neurons born in adulthood.It has been known for many years that the developing nervous system overproduces neurons. Many parts of the developing central nervous system retain only a fraction of the neurons originally produced (1-5). The conditions that determine this selective death are under intensive study (e.g., refs. 6-9). Neuronal death is also seen in some diseases ofthe adult human brain-e.g., Alzheimer and Parkinson diseases. Several studies (e.g., refs. 10-12) have looked at the factors or conditions that may prevent or delay neuronal death during development or in the adult diseased brain. There is hope that factors that prevent selective death during development may also rescue neurons that die during disease. But such studies need not be restricted to the developing brain. Neurogenesis and neuronal replacement occur spontaneously in a part of the song system of adult songbirds. This offers the opportunity to study neuronal death and replacement in a healthy adult vertebrate brain and in a system that controls a well-characterized behavior.Oscine songbirds acquire their song by reference to auditory information (13)(14)(15). The circuits involved in the acquisition and production of learned song have been described (16-19). One ofthe telencephalic nuclei, the high vocal center (HVC), necessary for the production of learned song (16,20,21), is of particular interest because it incorporates and replaces neurons in adulthood (22)(23)(24)(25)(26). More than half of the adult-formed neurons added to the HVC (26-28) grow an axon that reaches nucleus robustus archistriatalis (RA), on the efferent pathway for song production (16). The number of HVC neurons, including those that project to RA, ceases to increase in adulthood and neurogenesis in this system is part of a process of neuronal replacement (25,28,29).Earlier work (27) GBq; New England Nuclear). These birds received the PHIthymidine treatment at two times of the year, May (spring) or September (fall), and were divided into four groups as described in Table 1. All birds were weighed, anesthetized with 50 A1 of a dilution of Nembutal (Abbott; 10 mg/ml), and given FluoroGold [2% (wt/vol) solution in saline] microinj...

show abstract

Section: Discussionmentioning

confidence: 90%

The life span of new neurons in a song control nucleus of the adult canary brain depends on time of year when these cells are born.

Nottebohm

O'loughlin²,

Gould³

et al. 1994

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Sex differences exist in various aspects of their syrinxes. Male songbirds vocalize much more than females, and tracheal lumen size, overall mass, and size of muscle fibers are increased in adult males compared to females [13][14][15][16]. In addition, while variability can exist within a species and across types of sounds produced, some evidence exists for an average lateral asymmetry in the production of vocalizations.…”

Section: Introductionmentioning

confidence: 99%

Laterality in syrinx muscle morphology of the Japanese quail (Coturnix japonica)

Burke

Adkins‐Regan

Wade

2007

Physiology & Behavior

View full text Add to dashboard Cite

In the Japanese quail, normally only males crow, but treatment of adult females with testosterone (T) facilitates the behavior. The sternotrachealis muscles are thought to adjust the length of the trachea during inspiration and/or expiration and control rigidity of the cartilages of the vocal organ (syrinx) during phonation. These muscles are heavier in males than females, and T increases their mass in females [1,2]. To investigate sex differences in morphology and potential effects of T in more detail, we examined several components of male, female, and T-treated female quail syrinx. No group effects were detected on overall tracheal size, size of the tracheal lumen, quantity of cartilage, overall muscle volume, or cross-sectional muscle area. However, the area and estimated volume of the muscles were greater on the right than left, due to increased fiber number. The similarity across groups suggests that if the sternotrachealis muscles are critical for crowing, morphology in females is sufficient, and the sex difference in behavior has another source. In contrast, these muscles may not play as large a role as was hypothesized. If the increased number of fibers on the right has a functional consequence, it likely reflects one similar in the two sexes, for example a common role in vocalizations they each produce -the male's crow and the female's cricket call.

show abstract

“…The range of cellular effects influenced by hormonal stimulation in adult canaries is quite broad and includes changes in soma1 size and dendntic arbor, number and density of neurons, expression of neurotransmitter enzymes, and number and size of synapses (cf. Bleisch, Luine, and Nottebohm, 1984;Bottjer and Dignan, 1988;DeVoogd and Nottebohm, 198 1 : DeVoogd, Nixdorf, and Nottebohm, 1985;Luine, Nottebohm, Harding, and McEwen, 1980). The neural system controlling song behavior in zebra finches is also sexually dimorphic with respect to hormone sensitivity: song-control nuclei of adult males contain a much higher proportion of androgen-concentrating cells than do those of females (Arnold and Saltiel, 1979).…”

mentioning

confidence: 99%

Testosterone and the incidence of hormone target cells in song‐control nuclei of adult canaries

Bottjer¹,

Maier²

1991

J. Neurobiol.

View full text Add to dashboard Cite

Adult male canaries learn to produce high-amplitude complex courtship songs each breeding season, whereas females do not, and brain nuclei involved with the production of song behavior are much larger in breeding males than in nonbreeding males or females (Nottebohm, 1980, 1981). However, treatment of adult females with testosterone (T) causes them to produce male-like song and stimulates pronounced growth of some song-control brain nuclei such as the caudal nucleus of the ventral hyperstriatum (HVc). We reexamined the effects of T on song-control nuclei in deafened birds. In order to examine whether the pattern of hormone accumulation varies as a function of circulating testosterone levels we described the distribution of testosterone-concentrating cells in HVc and the magnocellular nucleus of the anterior neostriatum (MAN) in hearing adult male, female, and T-treated female canaries, as well as in deaf T-treated and untreated females. In contrast to our previous findings (Bottjer, Schoonmaker, and Arnold, 1986a), we observed no tendency in this study for testosterone-induced growth of HVc to be attenuated in deafened birds. There was no difference between deaf and hearing birds in the incidence of labeled cells within HVc. We also observed no sex or hormone-induced differences in the percentage of hormone-concentrating cells in HVc: normal females have approximately the same proportion of hormone target cells as do males and T-treated females. However, males normally have many more neurons in HVc than do control females, and systemic exposure to testosterone induces a pronounced increase in the number of HVc neurons of adult females. Therefore, the absolute number of hormone target cells in HVc is likely to be much greater in males and T-treated females than in normal females. As in HVc, there were no differences among groups in the proportion of labeled cells within lateral MAN (IMAN), a nucleus that has been implicated in song learning (Bottjer, Miesner and Arnold, 1984). In contrast, the incidence of hormone target cells in medial MAN (mMAN) did vary as a function of hormonal condition: although mMAN of normal females is rarely visible in Nissl-stained sections and cells in this region are not hormone labeled, mMAN is clearly visible in Nissl-stained sections of males and T-treated females and contains many hormone-labeled cells. This testosterone-induced change in the phenotype of mMAN cells suggests a possible role for mMAN in learned song behavior.

show abstract

Modification of synapses in androgen-sensitive muscle. I. Hormonal regulation of acetylcholine receptor number in the songbird syrinx

Cited by 56 publications

References 20 publications

The life span of new neurons in a song control nucleus of the adult canary brain depends on time of year when these cells are born.

The life span of new neurons in a song control nucleus of the adult canary brain depends on time of year when these cells are born.

Laterality in syrinx muscle morphology of the Japanese quail (Coturnix japonica)

Testosterone and the incidence of hormone target cells in song‐control nuclei of adult canaries

Contact Info

Product

Resources

About