Development of ability to initiate and maintain prolactin surges induced by uterine cervical stimulation in immature rats

M (Susan) Smith, J. A. Ramaley

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

The ability of uterine cervical stimulation (CS) to initiate prolactin surges was studied in immature rats. The cervix was stimulated with a glass rod for 60 sec at 1700 h (lights on 0600-1800 h). CS of 20- to 23-day-old rats failed to release prolactin the next morning at times corresponding to a nocturnal surge (0500-1100 h). In contrast, CS on day 24 resulted in typical nocturnal prolactin surges on days 25-27. However, no diurnal surges were observed. After CS on day 23, even though no prolactin surges occurred on day 24, nocturnal surges were observed on days 25 and 26. Therefore, the ability to retain the information from CS develops by day 23 whereas the ability to express the information as prolactin surges does not develop until day 25. Ovarian steroids did not alter the timing of this development, as only the magnitude of the surges was affected by the presence or absence of ovarian steroids. The failure to release prolactin after CS of androgen-sterilized females suggests that development of the ability to release prolactin is primarily a hypothalamic event. The relationship of a time of day signal to prolactin surges was studied im immature rats raised in constant light. Prolactin secretion increased immediately after CS but not at times corresponding to the nocturnal surge. Therefore, in the absence of an appropriate time of day signal, CS becomes a typical neuroendocrine reflex with hormone secretion increasing immediately after the stimulus.

Original languageEnglish (US)
Pages (from-to)351-357
Number of pages7
JournalEndocrinology
Volume102
Issue number2
StatePublished - 1978
Externally publishedYes

Fingerprint

Prolactin
Aptitude
Steroids
Light
Cervix Uteri
Androgens
Glass
Reflex
Hormones

ASJC Scopus subject areas

  • Endocrinology
  • Endocrinology, Diabetes and Metabolism

Cite this

Development of ability to initiate and maintain prolactin surges induced by uterine cervical stimulation in immature rats. / Smith, M (Susan); Ramaley, J. A.

In: Endocrinology, Vol. 102, No. 2, 1978, p. 351-357.

Research output: Contribution to journalArticle

@article{bb85c526e39c4e8baf526df318273336,
title = "Development of ability to initiate and maintain prolactin surges induced by uterine cervical stimulation in immature rats",
abstract = "The ability of uterine cervical stimulation (CS) to initiate prolactin surges was studied in immature rats. The cervix was stimulated with a glass rod for 60 sec at 1700 h (lights on 0600-1800 h). CS of 20- to 23-day-old rats failed to release prolactin the next morning at times corresponding to a nocturnal surge (0500-1100 h). In contrast, CS on day 24 resulted in typical nocturnal prolactin surges on days 25-27. However, no diurnal surges were observed. After CS on day 23, even though no prolactin surges occurred on day 24, nocturnal surges were observed on days 25 and 26. Therefore, the ability to retain the information from CS develops by day 23 whereas the ability to express the information as prolactin surges does not develop until day 25. Ovarian steroids did not alter the timing of this development, as only the magnitude of the surges was affected by the presence or absence of ovarian steroids. The failure to release prolactin after CS of androgen-sterilized females suggests that development of the ability to release prolactin is primarily a hypothalamic event. The relationship of a time of day signal to prolactin surges was studied im immature rats raised in constant light. Prolactin secretion increased immediately after CS but not at times corresponding to the nocturnal surge. Therefore, in the absence of an appropriate time of day signal, CS becomes a typical neuroendocrine reflex with hormone secretion increasing immediately after the stimulus.",
author = "Smith, {M (Susan)} and Ramaley, {J. A.}",
year = "1978",
language = "English (US)",
volume = "102",
pages = "351--357",
journal = "Endocrinology",
issn = "0013-7227",
publisher = "The Endocrine Society",
number = "2",

}

TY - JOUR

T1 - Development of ability to initiate and maintain prolactin surges induced by uterine cervical stimulation in immature rats

AU - Smith, M (Susan)

AU - Ramaley, J. A.

PY - 1978

Y1 - 1978

N2 - The ability of uterine cervical stimulation (CS) to initiate prolactin surges was studied in immature rats. The cervix was stimulated with a glass rod for 60 sec at 1700 h (lights on 0600-1800 h). CS of 20- to 23-day-old rats failed to release prolactin the next morning at times corresponding to a nocturnal surge (0500-1100 h). In contrast, CS on day 24 resulted in typical nocturnal prolactin surges on days 25-27. However, no diurnal surges were observed. After CS on day 23, even though no prolactin surges occurred on day 24, nocturnal surges were observed on days 25 and 26. Therefore, the ability to retain the information from CS develops by day 23 whereas the ability to express the information as prolactin surges does not develop until day 25. Ovarian steroids did not alter the timing of this development, as only the magnitude of the surges was affected by the presence or absence of ovarian steroids. The failure to release prolactin after CS of androgen-sterilized females suggests that development of the ability to release prolactin is primarily a hypothalamic event. The relationship of a time of day signal to prolactin surges was studied im immature rats raised in constant light. Prolactin secretion increased immediately after CS but not at times corresponding to the nocturnal surge. Therefore, in the absence of an appropriate time of day signal, CS becomes a typical neuroendocrine reflex with hormone secretion increasing immediately after the stimulus.

AB - The ability of uterine cervical stimulation (CS) to initiate prolactin surges was studied in immature rats. The cervix was stimulated with a glass rod for 60 sec at 1700 h (lights on 0600-1800 h). CS of 20- to 23-day-old rats failed to release prolactin the next morning at times corresponding to a nocturnal surge (0500-1100 h). In contrast, CS on day 24 resulted in typical nocturnal prolactin surges on days 25-27. However, no diurnal surges were observed. After CS on day 23, even though no prolactin surges occurred on day 24, nocturnal surges were observed on days 25 and 26. Therefore, the ability to retain the information from CS develops by day 23 whereas the ability to express the information as prolactin surges does not develop until day 25. Ovarian steroids did not alter the timing of this development, as only the magnitude of the surges was affected by the presence or absence of ovarian steroids. The failure to release prolactin after CS of androgen-sterilized females suggests that development of the ability to release prolactin is primarily a hypothalamic event. The relationship of a time of day signal to prolactin surges was studied im immature rats raised in constant light. Prolactin secretion increased immediately after CS but not at times corresponding to the nocturnal surge. Therefore, in the absence of an appropriate time of day signal, CS becomes a typical neuroendocrine reflex with hormone secretion increasing immediately after the stimulus.

UR - http://www.scopus.com/inward/record.url?scp=0017877857&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0017877857&partnerID=8YFLogxK

M3 - Article

C2 - 743961

AN - SCOPUS:0017877857

VL - 102

SP - 351

EP - 357

JO - Endocrinology

JF - Endocrinology

SN - 0013-7227

IS - 2

ER -