Functional membrane changes due to tumor induction in rat pituitary cell cultures

M. Gálfi, W. K A Khalil, Z. Valkusz, L. Gáspár, A. Juhász, J. Julesz, J. Molnár

Research output: Contribution to journalArticle

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Abstract

Membrane functions in tumorous cells are different from those in healthy cells. The aim of the present study was to investigate the changes in pituitary cell membrane functions and hormone secretion after tumor induction in vivo and in vitro. Prolactinomas were induced in vivo in female Wistar rats with estrone acetate. Normal anterior pituitaries and prolactinomas of female Wistar rats were dissociated enzymatically and mechanically, then cultured on collagen-treated plastic dishes. Some normal anterior pituitary cultures were treated with benz(c)acridines as tumorigenic agents in vitro. Intracellular 3′,5′-cyclic-adenosine monophosphate (cAMP) levels were determined by a competitive binding technique, membrane fluidity was assayed by fluorescence anisotropy, and ATP-ase activities were estimated via ATP loss. The results indicated decreased membrane fluidity in tumorous cell cultures. However, in vitro benz(c)acridine treatment exerted more pronounced effects than those observed after in vivo estrone treatment. The ATP-ase activities were highly increased in benz(c)acridine-treated cells and in estrogen-induced prolactinoma cells, more strongly so in the former ones. The intracellular cAMP levels were higher than normal in both of them. The results concerning the ACTH, alpha-MSH, PRL and GH levels of normal and tumorous cell cultures were published in our previous study. Our findings show that the tumorous transformation of pituitary cells can cause significant changes in functional membrane parameters and hormone secretion. Decreased membrane fluidity was accompanied by an increased exocytosis (hormone release) and adenylate cyclase activity in tumorous cells.

Original languageEnglish
Pages (from-to)531-535
Number of pages5
JournalJournal of Experimental and Clinical Cancer Research
Volume19
Issue number4
Publication statusPublished - 2000

Fingerprint

Cell Culture Techniques
Prolactinoma
Membrane Fluidity
Membranes
Neoplasms
Adenosine Triphosphate
Hormones
Cyclic AMP
Wistar Rats
alpha-MSH
Fluorescence Polarization
Competitive Binding
Estrone
Exocytosis
Adenylyl Cyclases
Adrenocorticotropic Hormone
Plastics
Estrogens
Collagen
Cell Membrane

Keywords

  • Adenohypophysis
  • ATP-ase
  • Benz(c)acridine
  • cAMP
  • Membrane fluidity
  • Tumorigenesis

ASJC Scopus subject areas

  • Cancer Research
  • Oncology

Cite this

Functional membrane changes due to tumor induction in rat pituitary cell cultures. / Gálfi, M.; Khalil, W. K A; Valkusz, Z.; Gáspár, L.; Juhász, A.; Julesz, J.; Molnár, J.

In: Journal of Experimental and Clinical Cancer Research, Vol. 19, No. 4, 2000, p. 531-535.

Research output: Contribution to journalArticle

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