Laboratory Assessment of Prolactin Status

Abstract

SUMMARYThe laboratory assessment of prolactin status was evaluated by detailed study of 921 subjects (587 normal subjects and 334 patients with pathological conditions). The effect on serum prolactin levels of age, sex, circadian rhythm, pulsatility of secretion, stress, drug ingestion, and pregnancy was defined in normal subjects. The normal prolactin responses to stimulation (TRH, metoclopramide) and suppression (t-dopa, bromocriptine) were also determined. Basal prolactin levels were measured in patients with defined pathological conditions including prolactinoma, idiopathic hyperprolactinaemia, acromegaly, Cushing's disease, chronic renal failure, primary hypothyroidism, pituitary ablation, Kallman's syndrome, Nelson's syndrome, growth hormone deficiency, gonadotrophin deficiency, craniopharyngioma, panhypopituitarism, and chronic progressive arthropathy. Based on these data, a strategy for the routine laboratory assessment of prolactin status is outlined. NORMAL SUBJECTS

Bupropion fails to affect plasma prolactin and growth hormone in normal subjects [letter]

“…The sensitivity of the prolactin assay used in the study was comparable to those used by previous workers (Cowden et al, 1979;Stem et al, 1979). Basal values obtained in this study (between 10.00 and 11.00 h) were generally comparable with those reported previously (Frantz, 1977;Cowden et al, 1979).…”

“…The sensitivity of the prolactin assay used in the study was comparable to those used by previous workers (Cowden et al, 1979;Stem et al, 1979). Basal values obtained in this study (between 10.00 and 11.00 h) were generally comparable with those reported previously (Frantz, 1977;Cowden et al, 1979). Since prolactin secretion during the night appears to be increased by sleep (Sassin et al, 1973) the best time for measurement of basal prolactin concentrations may depend on the circumstances of the particular study.…”

“…It has been recommended that blood for determination of basal prolactin values should be taken between 09.00 h and 12.00 h. In the present study plasma prolactin levels were declining rapidly until 10.00 h. Four of the five women in our study were taking the contraceptive pill. Cowden et al (1979) suggested that women on the 'pill' tend to have higher basal prolactin levels but in their study blood was taken from such women between 18.00 h and 20.00 h. In our study plasma prolactin appeared to be elevated at this time of day. The 'basal' prolactin concentrations (at 10.00 h to 11.00 h) in our subjects were not unduly elevated.…”

Prognostic significance of serum prolactin levels in advanced breast cancer

“…Indeed such arguments have led to the suggestion (Jeffcoate, 1978) that serial blood sampling would be more advantageous in the estimation of prolactin status. However, a number of investigations have concluded that venepuncture rarely, if ever, induces prolactin release (Koninckx, 1978;Cowden et al, 1979;Pearce et al, 1980) and that frequent sampling does not improve the value of a result (Pearce et al, 1980;Moult et al, 1981 present report may be viewed with confidence. There are, however, a variety of drugs which can affect prolactin release (Fluckinger, 1972) and it is unfortunate that we were unable to take account of this.…”

“…The defined time period was chosen to avoid major variation due to the diurnal rhythm of prolactin. By 9.30 am, the fall of prolactin levels from their nocturnal, sleep-induced peak has reached a plateau (Cowden et al, 1979). It has been suggested that artefactual high prolactin levels may occur due to pulsatile release (Ehara et al, 1973) or stress at venepuncture (Koninckx, 1978).…”