Bromocriptine treatment reduces the cell size in human macroprolactinomas: A morphometric study

M. Bassetti, A. Spada, G. Pezzo, G. Giannattasio

Research output: Contribution to journalArticlepeer-review


A morphological study was carried out on eight macroprolactinomas surgically removed from untreated patients and on nine macroprolactinomas removed from patients treated with bromocriptine (Brc; seven from patients treated for 6 weeks and two from patients treated for 1 yr). All treated patients had both serum PRL levels and tumor size (by computed tomographic scan) reduced. The study was carried out using light, immunofluorescence, and electron microscopic techniques and electron microscopic morphometry. By immunofluorescence microscopy, all tumors consisted of cells positive for PRL. In some treated tumors, the fluorescence was more marked than in untreated tumors. By light and electron microscopy and by morphometry, significant reductions in cell size were observed in the adenomas from Brc-treated patients. Both the cytoplasm and the nucleus shrank, but the reduction of the cytoplasm was much greater than that of the nucleus. The shrinkage of the cytoplasm was a consequence of marked involution of the rough endoplasmic reticulum and the Golgi complex in Brc-treated tumors. This effect may be related to inhibition of PRL synthesis by the drug. In some tumors from treated patients, the number of secretory granules was increased. No differences were observed between tumors from patients treated for 6 weeks and those from patients treated for 1 yr. The observed reduction in cell size by Brc could explain, at least in part, the well known size reduction of PRL-secreting adenomas in patients treated with the drug.

Original languageEnglish
Pages (from-to)268-273
Number of pages6
JournalJournal of Clinical Endocrinology and Metabolism
Issue number2
Publication statusPublished - 1984

ASJC Scopus subject areas

  • Biochemistry
  • Endocrinology, Diabetes and Metabolism

Fingerprint Dive into the research topics of 'Bromocriptine treatment reduces the cell size in human macroprolactinomas: A morphometric study'. Together they form a unique fingerprint.

Cite this