Infrequent low dose testosterone treatment maintains male sexual behavior in Syrian hamsters

David J. Piekarski, David M. Routman, Elanor E. Schoomer, Joseph R. Driscoll, Jin Ho Park, Matthew Butler, Irving Zucker

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

Testosterone (T) secreted in short pulses several times each day is essential for the maintenance of male sex behavior (MSB) in mammals. Blood T concentrations are relatively low during inter-pulse intervals. Assessment of androgenic influences on MSB of rodents has, with very few exceptions, involved either injections of pure or esterified hormones dissolved in oil or implantation of constant release capsules that generate supraphysiological and/or constantly elevated T concentrations. The minimum daily concentration of T necessary to maintain and restore MSB when T is delivered as a discrete short pulse remains unspecified; nor is it known whether infrequent T pulses in the physiological range sustain MSB. To address these questions, we varied T injection concentrations and frequencies in castrated, sexually-experienced Syrian hamsters. All males injected daily with an aqueous vehicle failed to display the ejaculatory reflex 5 weeks after castration. Once daily 15 μg subcutaneous T injections both maintained and restored MSB, whereas once daily 5 μg T injections resulted in fewer males ejaculating and longer ejaculation latencies. Substantially higher T doses were required to restore MSB in previous studies when T was administered in an oil vehicle. 50 μg T maintained MSB in most hamsters injected once every 4 or 7 days, despite long intervals between injections during which circulating T was undetectable or well below physiological concentrations. Some T regimens that maintained MSB were associated with subnormal seminal vesicle and ventral prostate weights. The demonstration that relatively brief, infrequent elevations of T are sufficient to support MSB provides a useful model to assess the neuroendocrine basis of MSB and raises the possibility that infrequent low dose androgen replacement protocols may restore sex behavior to hypogonadal men without inducing some of the negative side-effects associated with more frequent, higher dose treatments.

Original languageEnglish (US)
Pages (from-to)182-189
Number of pages8
JournalHormones and Behavior
Volume55
Issue number1
DOIs
StatePublished - Jan 2009
Externally publishedYes

Fingerprint

Mesocricetus
Sexual Behavior
Testosterone
Therapeutics
Injections
Oils
Ejaculation
Seminal Vesicles
Castration
Subcutaneous Injections
Cricetinae
Androgens
Capsules
Reflex
Prostate
Mammals
Rodentia
Maintenance
Hormones

Keywords

  • Copulation
  • Male Syrian hamsters
  • Testosterone

ASJC Scopus subject areas

  • Endocrinology
  • Behavioral Neuroscience
  • Endocrine and Autonomic Systems

Cite this

Piekarski, D. J., Routman, D. M., Schoomer, E. E., Driscoll, J. R., Park, J. H., Butler, M., & Zucker, I. (2009). Infrequent low dose testosterone treatment maintains male sexual behavior in Syrian hamsters. Hormones and Behavior, 55(1), 182-189. https://doi.org/10.1016/j.yhbeh.2008.10.003

Infrequent low dose testosterone treatment maintains male sexual behavior in Syrian hamsters. / Piekarski, David J.; Routman, David M.; Schoomer, Elanor E.; Driscoll, Joseph R.; Park, Jin Ho; Butler, Matthew; Zucker, Irving.

In: Hormones and Behavior, Vol. 55, No. 1, 01.2009, p. 182-189.

Research output: Contribution to journalArticle

Piekarski, DJ, Routman, DM, Schoomer, EE, Driscoll, JR, Park, JH, Butler, M & Zucker, I 2009, 'Infrequent low dose testosterone treatment maintains male sexual behavior in Syrian hamsters', Hormones and Behavior, vol. 55, no. 1, pp. 182-189. https://doi.org/10.1016/j.yhbeh.2008.10.003
Piekarski, David J. ; Routman, David M. ; Schoomer, Elanor E. ; Driscoll, Joseph R. ; Park, Jin Ho ; Butler, Matthew ; Zucker, Irving. / Infrequent low dose testosterone treatment maintains male sexual behavior in Syrian hamsters. In: Hormones and Behavior. 2009 ; Vol. 55, No. 1. pp. 182-189.
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