Gordon L. Noel

Galactorrhea: a study of 235 cases, including 48 with pituitary tumors.

Abstract An analysis of 235 patients with galactorrhea (5.5 per cent males) showed that 20 per cent of all patients, and 34 per cent of women with associated amenorrhea, had radiologically evident pituitary tumors; these patients had the highest serum prolactin concentrations. The largest single group (32 per cent) consisted of women with idiopathic galactorrhea without amenorrhea; prolactin was normal in 86 per cent of these cases. Five patients had the empty-sella syndrome. Prolactin response was tested in selected patients by thyrotropin-releasing hormone, chlorpromazine, L-dopa, 24-hour sampling and other means. Tests with thyrotropin-releasing hormone were most useful in identifying patients with pituitary tumors. Surgery and radiotherapy lowered prolactin to a similar degree in patients with tumor, but galactorrhea and amenorrhea often persisted after treatment. The ergot derivatives, bromergocryptine and lergotrile mesylate, lowered prolactin in all 18 patients with idiopathic hyperprolactinemia or...

Effects of l-dopa on prolactin secretion in humans

Publisher Summary This chapter describes a study analyzing effects of L-DOPA on prolactin secretion in humans. In the study, subjects were healthy normal volunteers aged 21–27, studied in the morning after an overnight fast. Blood samples were collected through an antecubital vein at the start of the experiment. L-dopa and MK-486 were administered orally. Thyrotropin releasing hormone (TRH), either 100 μg or 500 μg, was given intravenously over 30 s. Prolactin was measured by homologous human radioimmunoassay. Growth hormone was also measured by radioimmunoassay. It was observed that TRH given alone to seven normal women and seven normal men caused the expected acute rises in plasma prolactin. Women as a group were more responsive than men to TRH; a greater responsiveness in women has also been noted to other kinds of prolactin releasing. Several days after the studies with TRH alone, the same subjects were given the same dose of TRH but were pretreated with 500 mg of L-dopa an hour beforehand; 11 of the 14 subjects received an additional 250 mg of L-dopa 30 min before the TRH. Except for one woman whose TRH response was unchanged by L-dopa; a clear suppressive effect was evident in all subjects.

EFFECTS OF L-DOPA ON PROLACTIN SECRETION IN HUMANS

Publisher Summary This chapter describes a study analyzing effects of L-DOPA on prolactin secretion in humans. In the study, subjects were healthy normal volunteers aged 21–27, studied in the morning after an overnight fast. Blood samples were collected through an antecubital vein at the start of the experiment. L-dopa and MK-486 were administered orally. Thyrotropin releasing hormone (TRH), either 100 μg or 500 μg, was given intravenously over 30 s. Prolactin was measured by homologous human radioimmunoassay. Growth hormone was also measured by radioimmunoassay. It was observed that TRH given alone to seven normal women and seven normal men caused the expected acute rises in plasma prolactin. Women as a group were more responsive than men to TRH; a greater responsiveness in women has also been noted to other kinds of prolactin releasing. Several days after the studies with TRH alone, the same subjects were given the same dose of TRH but were pretreated with 500 mg of L-dopa an hour beforehand; 11 of the 14 subjects received an additional 250 mg of L-dopa 30 min before the TRH. Except for one woman whose TRH response was unchanged by L-dopa; a clear suppressive effect was evident in all subjects.

GALACTORRHEA: A STUDY OF 235 CASES, INCLUDING 48 WITH PITUITARY TUMORS

An analysis of 235 patients with galactorrhea (5.5 per cent males) showed that 20 per cent of all patients, and 34 per cent of women with associated amenorrhea, had radiologically evident pituitary tumors; these patients had the highest serum prolactin concentrations. The largest single group (32 per cent) consisted of women with idiopathic galactorrhea without amenorrhea; prolactin was normal in 86 per cent of these cases. Five patients had the empty-sella syndrome. Prolactin response was tested in selected patients by thyrotropin-releasing hormone, chlorpromazine, L-dopa, 24-hour sampling and other means. Tests with thyrotropin-releasing hormone were most useful in identifying patients with pituitary tumors. Surgery and radiotherapy lowered prolactin to a similar degree in patients with tumor, but galactorrhea, and amenorrhea often persisted after treatment. The ergot derivatives, bromergocryptine and lergotrile mesylate, lowered prolactin in all 18 patients with idiopathic hyperprolactinemia or pituitary tumor, stopped galactorrhea in over 50 per cent, restored menses in over 70 per cent, and allowed pregnancy in three.