Prolactin response to morphine in intact and adrenalectomized lactating rats

D. T. Kiem, M. Fekete, L. Bartha, Gy Nagy, G. Makara

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

To examine the hypothesis that the increased adrenocortical activity during lactation induced the loss of the prolactin (PRL) -releasing effect of morphine, we studied the effect of morphine in adrenalectomized (ADX) and sham-operated primiparous lactating Wistar rats. Animals were adrenalectomized 4 days after delivery. On day 11 of lactation (7 days after ADX), pups were separated from their mother 2 h before morphine or haloperidol injection. Intravenous injection of 5 mg/kg morphine did not change plasma PRL levels in the sham-operated lactating rats, but it resulted in a significant increase of plasma PRL levels in ADX lactating animals, with or without corticosterone replacement. Catalepsy following 10 mg/kg i.v. morphine was also markedly enhanced in ADX lactating animals. The PRL response to 0.5 mg/kg haloperidol was higher in ADX lactating animals than that in the controls. Morphine given 2 h after haloperidol treatment resulted in a further increase of plasma PRL in ADX, but not in the sham-operated lactating animals. These results suggest that adrenal hyperfunction may lead to a loss of sensitivity to morphine during lactation.

Original languageEnglish
Pages (from-to)171-174
Number of pages4
JournalBrain Research
Volume563
Issue number1-2
DOIs
Publication statusPublished - Nov 1 1991

Fingerprint

Prolactin
Morphine
Haloperidol
Lactation
Catalepsy
Corticosterone
Intravenous Injections
Wistar Rats
Injections

Keywords

  • Glucocorticoid
  • Lactating rat
  • Opiate sensitivity
  • Prolactin

ASJC Scopus subject areas

  • Developmental Biology
  • Molecular Biology
  • Clinical Neurology
  • Neuroscience(all)

Cite this

Prolactin response to morphine in intact and adrenalectomized lactating rats. / Kiem, D. T.; Fekete, M.; Bartha, L.; Nagy, Gy; Makara, G.

In: Brain Research, Vol. 563, No. 1-2, 01.11.1991, p. 171-174.

Research output: Contribution to journalArticle

Kiem, D. T. ; Fekete, M. ; Bartha, L. ; Nagy, Gy ; Makara, G. / Prolactin response to morphine in intact and adrenalectomized lactating rats. In: Brain Research. 1991 ; Vol. 563, No. 1-2. pp. 171-174.
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