Springer Nature is making SARS-CoV-2 and COVID-19 research free. View research | View latest news | Sign up for updates

Evidence for a direct effect of androgens upon electroreceptor tuning

  • 57 Accesses

  • 33 Citations


  1. 1.

    Tuberous electroreceptors of individual wave type weakly electric fish are tuned to the fundamental frequency of that fish's electric organ discharge (EOD). EOD frequency and receptor best frequency (BF) are both lowered following systemic injection of 5-α-dihydrotestosterone (DHT). A previous study (Meyer et al. 1984) showed that the effect of DHT on the EOD generating circuitry was independent of an ongoing EOD and suggested that its effect on electroreceptor tuning was indirect, possibly mediated by the electric field. We have continued these studies to determine the factors which influence electroreceptor tuning.

  2. 2.

    Baseline recordings of EOD frequency, receptor oscillations, and single afferent tuning curves were taken. After fish were electrically silenced by spinal cord transection they were injected daily with either DHT or saline or were implanted with either DHT-filled or empty silastic capsules.

  3. 3.

    As previously reported, the EOD frequency (determined from pacemaker nucleus recordings) was lowered in DHT-treated, transected fish and increased in control fish.

  4. 4.

    Similarly, receptor tuning was lowered in the DHT-treated, silenced fish. Oscillation frequencies decreased in both treated and control groups, but significantly more in the hormone group. Single afferent best frequencies were lowered in both DHT groups and raised in their respective control groups.

  5. 5.

    In another series of experiments exogenous electric fields capable of driving receptors in a 1-to-1 phase-locked manner were placed around silenced fish. We were unable to elicit any shift in pacemaker frequency or electroreceptor tuning regardless of stimulus field geometry.

  6. 6.

    Four transected fish were injected with DHT and placed in exogenous electric fields of higher frequency than their original EOD. Even in the presence of a higher frequency electric field, DHT lowered EOD frequency and afferent BF.

  7. 7.

    We conclude that androgens produce effects both on the EOD generating circuitry, probably at the level of the pacemaker nucleus, and on electroreceptors, probably, ultimately, on receptor cell membrane conductances. These effects occur in parallel allowing the two parameters to remain well matched. In contrast to former predictions, exogenous electric fields alone appear unable to shift receptor tuning.

This is a preview of subscription content, log in to check access.



electric organ discharge


normalized change in electric organ discharge frequency

BF :

best frequency

ΔBFp :

normalized change in best frequency


receptor oscillation frequency


normalized change in receptor oscillation frequency




  1. Bass AH, Hopkins CD (1983) Hormonal control of sexual differentiation: changes in electric organ discharge waveform. Science 220:971–974

  2. Bass AH, Hopkins CD (1984) Shifts in frequency tuning of electroreceptors in androgen-treated mormyrid fish. J Comp Physiol A 155:713–724

  3. Bass AH, Hopkins CD (1985) Hormonal control of sex differences in the electric organ discharge (EOD) of mormyrid fishes. J Comp Physiol A 156:587–604

  4. Bass AH, Volman SF (1985) Steroid-induced changes in action potential waveforms of an electric organ. Neurosci Abstr 11:159

  5. Bass A, Segil N, Kelley D (1984) A steroid sensitive electromotor pathway in mormyrid fish: electric organ morphology, androgen receptor biochemistry and steroid autoradiography. Neurosci Abstr 10:927

  6. Bastian J (1977) Variations in the frequency response of electroreceptors dependent on receptor location in weakly electric fish (Gymnotoidei) with a pulse discharge. J Comp Physiol 121:53–64

  7. Bennett MVL (1967) Mechanisms of electroreceptors. In: Cahn P (ed) Lateral line detectors. Univ Indiana Press, Bloomington, pp 313–393

  8. Bennett MVL (1971) Electric organs. In: Hoar WS, Randall LDJ (eds) Fish physiology, vol 2. Academic Press, New York, pp 347–491

  9. Ellis MM (1913) The gymnotid eels of tropical America. Mem Carnegie Museum 6:109–204

  10. Enger PS, Szabo T (1968) Effects of temperature on discharge rate of the electric organ of some gymnotoids. Comp Biochem Physiol 27:625–627

  11. Fettiplace R, Crawford AC (1978) The coding of sound pressure and frequency in cochlear hair cells of the terrapin. Proc R Soc London B 203:209–218

  12. Fostier A, Jalabert B, Billard R, Breton B, Zohar Y (1983) The gonadal steroids. In: Hoar WS, Randall DJ, Donaldson EM (eds) Fish physiology, vol IXa. Academic Press, New York, pp 277–372

  13. Hagedorn M, Carr CE (1985) Single electrocytes produce a sexually dimorphic signal in South American electric fish,Hypopomus occidentalis (Gymnotiformes, Hypopomidae). J Comp Physiol A 156:511–523

  14. Hagedorn M, Heiligenberg W (1985) Court and spark: electric signals in the courtship and mating of gymnotoid fish. Anim Behav 33:254–265

  15. Hopkins CD (1972) Sex differences in electric signalling in an electric fish. Science 176:1035–1037

  16. Hopkins CD (1976) Stimulus filtering and electroreceptors in three species of gymnotoid fish. J Comp Physiol 111:171–207

  17. Hopkins CD (1980) Evolution of electric communication channels of mormyrids. Behav Ecol Sociobiol 7:1–13

  18. Idler DR, Truscott B (1972) Corticosteroids in fish. In: Idler DR (ed) Steroids in nonmammalian vertebrates. Academic Press, New York, pp 127–252

  19. Kirschbaum F (1983) Myogenic electric organ precedes the neurogenic organ in apteronotid fish. Naturwissenschaften 70:205

  20. Koch C (1984) Cable theory in neurons with active linearized membranes. Biol Cybern 50:15–23

  21. Lewis RS, Hudspeth AJ (1983a) Voltage- and ion-dependent conductances in solitary vertebrate hair cells. Nature 304:538–541

  22. Lewis RS, Hudspeth AJ (1983b) Frequency tuning and ionic conductances in hair cells of the bullfrog's sacculus. In: Klinke R, Hartman R (eds) Hearing — Physiological bases and psychophysics. Springer, Berlin Heidelberg New York Tokyo, pp 17–24

  23. McEwen BS (1981) Neural gonadal steroid actions. Science 211:1303–1311

  24. Meyer JH (1983) Steroid influences upon the discharge frequencies of weakly electric fish. J Comp Physiol 153:29–37

  25. Meyer JH (1984) Steroid influences upon discharge frequencies of intact and isolated pacemakers of weakly electric fish. J Comp Physiol A 154:659–668

  26. Meyer JH, Zakon HH (1982) Androgens alter the tuning of electroreceptors. Science 217:635–637

  27. Meyer JH, Zakon HH, Heiligenberg W (1984) Steroid influences upon the electrosensory system of weakly electric fish: direct effects upon discharge frequencies with indirect effects upon electroreceptor tuning. J Comp Physiol A 154:625–631

  28. Pfaff DW, McEwen BS (1983) Actions of estrogens and progestins on nerve cells. Science 219:808–814

  29. Szabo T (1974) Anatomy of the specialized lateral line organs of electroreception. In: Fessard AE (ed) Electroreceptors and other spezialized receptors in lower vertebrates (Handbook of sensory physiology, vol III/3). Springer, Berlin Heidelberg New York, pp 13–58

  30. Viancour T (1979) Electroreceptors of weakly electric fish. II. Individually tuned receptor oscillations. J Comp Physiol 133:327–338

  31. Watson D, Bastian J (1979) Frequency response characteristics of electroreceptors in the weakly electric fish,Gymnotus carapo. J Comp Physiol 134:191–202

  32. Westby GWM, Kirschbaum F (1981) Sex differences in the electric organ discharge ofEigenmannia virescens and the effect of gonadal maturation. In: Szabo T, Gzeh G (eds) Sensory physiology of lower aquatic vertebrates. Pergammon Press, Oxford, pp 179–194

  33. Westby GWM, Kirschbaum F (1982) Sex differences in the waveform of the pulse-type electric fish,Pollimyrus isidori (Mormyridae). J Comp Physiol 145:39–403

  34. Wingfield JC, Farner D (1975) The determination of five steroids in avian plasma by radioimmunoassay and competitive protein binding. Steroid 26:311–327

  35. Yialamas D, Zakon HH (1984) Tuning of newly generated electroreceptors. Neurosci Abstr 10:193

  36. Zakon HH (1984a) Postembryonic changes in the peripheral electrosensory system of a weakly electric fish: addition of receptor organs with age. J Comp Neurol 228:557–570

  37. Zakon HH (1984b) The ionic basis of the oscillatory receptor potential of tuberous electroreceptors inSternopygus. Neurosci Abstr 10:193

  38. Zakon HH, Meyer JH (1983) Plasticity of electroreceptor tuning in the weakly electric fish,Sternopygus dariensis. J Comp Physiol 153:477–487

  39. Zipser B, Bennett MVL (1973) Tetrodotoxin resistant electrically excitable responses of receptor cells. Brain Res 62:253–259

Download references

Author information

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Keller, C.H., Zakon, H.H. & Sanchez, D.Y. Evidence for a direct effect of androgens upon electroreceptor tuning. J. Comp. Physiol. 158, 301–310 (1986). https://doi.org/10.1007/BF00603614

Download citation


  • Good Frequency
  • Electric Organ Discharge
  • Good Frequency
  • Spinal Cord Transection
  • Respective Control Group