Pattern of secretion of luteinizing hormone and testosterone in the sexually mature male turkey

Gen Comp Endocrinol. 1991 Dec;84(3):447-60. doi: 10.1016/0016-6480(91)90094-m.

Abstract

Whether luteinizing hormone (LH) and testosterone (T) are secreted in pulsatile patterns was determined in sexually mature male turkeys. Turkeys were chronically cannulated and serially bled for three 8-hr periods covering the 24-hr day (14L:10D, n = 7, series B), or for two 12-hr periods covering the 24-hr day (14L:10D, n = 4, series C). Pulses of both LH and T occurred during both the light and dark portions of the 24-hr day. A portion of the secretory episodes of T, where the baseline level of LH was relatively low, was associated with prior peaks of LH secretion. Secretory episodes of T also occurred, where baseline levels of LH and T were both relatively high, without detection of prior peaks of LH. No differences were found between the photophase and scotophase portions of the photoperiod for either LH or T concentration. It is concluded that T is secreted in a pulsatile pattern in sexually mature male turkeys. However, LH is secreted in a pulsatile pattern only when baseline levels of both LH and T are relatively low. Neither LH nor T secretion is entrained by the photoperiod. Corticosterone was measured in hourly samples, but no changes in concentration occurred in association with the photoperiod.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Body Weight
  • Corticosterone / metabolism
  • Light
  • Luteinizing Hormone / metabolism*
  • Male
  • Periodicity
  • Radioimmunoassay
  • Semen
  • Sex Characteristics
  • Testosterone / metabolism*
  • Turkeys / physiology*

Substances

  • Testosterone
  • Luteinizing Hormone
  • Corticosterone