Prolactin Secretion in Healthy Adults Is Determined by Gender, Age and Body Mass Index

Abstract

BackgroundProlactin (PRL) secretion is quantifiable as mean, peak and nadir PRL concentrations, degree of irregularity (ApEn, approximate entropy) and spikiness (brief staccato-like fluctuations).HypothesisDistinct PRL dynamics reflect relatively distinct (combinations of) subject variables, such as gender, age, and BMI.LocationClinical Research Unit.SubjectsSeventy-four healthy adults aged 22–77 yr (41 women and 33 men), with BMI 18.3–39.4 kg/m2.MeasuresImmunofluorometric PRL assay of 10-min samples collected for 24 hours.ResultsMean 24-h PRL concentration correlated jointly with gender (P<0.0001) and BMI (P = 0.01), but not with age (overall R2 = 0.308, P<0.0001). Nadir PRL concentration correlated with gender only (P = 0.017) and peak PRL with gender (P<0.001) and negatively with age (P<0.003), overall R2 = 0.325, P<0.0001. Forward-selection multivariate regression of PRL deconvolution results demonstrated that basal (nonpulsatile) PRL secretion tended to be associated with BMI (R2 = 0.058, P = 0.03), pulsatile secretion with gender (R2 = 0.152, P = 0.003), and total secretion with gender and BMI (R2 = 0.204, P<0.0001). Pulse mass was associated with gender (P = 0.001) and with a negative tendency to age (P = 0.038). In male subjects older than 50 yr (but not in women) approximate entropy was increased (0.942±0.301 vs. 1.258±0.267, P = 0.007) compared with younger men, as well as spikiness (0.363±0.122 vs. 0463±2.12, P = 0.031). Cosinor analysis disclosed higher mesor and amplitude in females than in men, but the acrophase was gender-independent. The acrophase was determined by age and BMI (R2 = 0.186, P = 0.001).ConclusionIn healthy adults, selective combinations of gender, age, and BMI specify distinct PRL dynamics, thus requiring balanced representation of these variables in comparative PRL studies.

Assessment of Thyroid Functions Test among Hyperprolactinemic Sudanese Infertile Females

“…Results of this study noted a significantly inversely correlation between PRL and the age in whole study population, this finding agree with many studies which found an association between PRL secretion and the age [48,49].…”

Assessment of Serum Gonadotropins and Prolactin Level Among Oligo and Azoospermia Patients.

“…Evidence from previous finding considered this observation is consistent with altered (increased) dopaminergic tonus in the elderly during the sleep period (23).Positive correlation was observed between prolactin and LH (R 0.398, p-value 0.002). Similarity to ours, Kazanci, showed that, prolactin potentiates the stimulatory effects of LH on testicular steroidogenesis furthermore prolactin activates leydig cells by increasing their responsiveness to LH (24).…”

The Endocrinology of Ageing: A Mini-Review

“…Peak concentrations of this hormone, which occur shortly prior to the onset of sleep, have been demonstrated to negatively correlate with age [46,47]. This, and reduced pulse amplitude during sleep in older age, indicates decreased dopaminergic inhibitory action on prolactin production in the elderly during the sleep period [15,26].…”