title: Recovery pattern of hypothalamo-pituitary-testicular axis in patients with macroprolactinomas after treatment with cabergoline.
abstract: OBJECTIVE
  Hyperprolactinaemia affects testicular functions by influencing hypothalamo-pituitary-testicular (HPT) axis at various levels. Available literature on the level of defect, time course of improvement of gonadal functions and its relation with decline in prolactin levels is scanty. We carried out this study to evaluate the HPT axis in patients with macroprolactinomas, before and six months after cabergoline therapy.
  
  
  METHODS
  Fifteen men with macroprolactinomas underwent gonadotropin and testosterone response to their respective stimuli before and after six months of cabergoline therapy.
  
  
  RESULTS
  Serum prolactin levels decreased after six months of therapy. Pretreatment, mean lutenizing and follicle stimulating hormones (LH and FSH) levels were 2.0 ± 0.4 and 1.4 ± 0.2 IU/l, respectively. However, LH and FSH responses to GnRH were preserved in majority of the patients and LH peaked to 12.1 ± 2.3 IU/l (P<0.01), while FSH to 2.9 ± 0.4 IU/l suggesting the influence of hyperprolactinaemia at the level of hypothalamus with preserved gonadotrope reserve. After cabergoline therapy, there was an increase in basal as well as stimulated LH and FSH levels, though these were not statistically significant when compared to respective pretherapy levels. Basal testosterone (T) levels significantly improved after therapy, but peak T response to hCG was similar at both pre- and post treatment. A significant correlation was observed between peak LH and peak T at baseline (r=0.53, P<0.01) and it further strengthened after therapy (r=0.70, P<0.01). After cabergoline therapy, there was significant improvement in seminal volume, sperm count and motility and sperm count correlated with peak FSH response (r=0.53, P<0.05).
  
  
  CONCLUSIONS
  Hyperprolactinaemia affects testicular functions probably by influencing at the level of hypothalamus resulting in subnormal basal secretion of gonadotropins required for optimal testicular functions.
authors: Department of Endocrinology, Postgraduate Institute of Medical Education & Research, Chandigarh, India.
authors: Rama
authors: R
authors: Walia
authors: Anil
authors: A
authors: Bhansali
authors: Pinaki
authors: P
authors: Dutta
authors: Niranjan
authors: N
authors: Khandelwal
authors: Ravinder
authors: R
authors: Sialy
authors: Sanjay
authors: S
authors: Bhadada
mesh_terms: D000704:Analysis of Variance; D000077465:Cabergoline; D004797:Enzyme-Linked Immunosorbent Assay; D004873:Ergolines / Q000494:pharmacology / Q000627:therapeutic use*; D005640:Follicle Stimulating Hormone / Q000097:blood; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology; D006801:Humans; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism*; D007986:Luteinizing Hormone / Q000097:blood; D008279:Magnetic Resonance Imaging; D008297:Male; D010911:Pituitary Neoplasms / Q000188:drug therapy* / Q000473:pathology; D011388:Prolactin / Q000097:blood; D015175:Prolactinoma / Q000188:drug therapy* / Q000473:pathology; D011863:Radioimmunoassay; D013076:Sperm Count; D013081:Sperm Motility / Q000187:drug effects; D013737:Testis / Q000378:metabolism*; D013739:Testosterone / Q000097:blood; D013997:Time Factors
chemical_list: D004873:Ergolines; D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; D011388:Prolactin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D000077465:Cabergoline