Hypothalamic control of gonadotrophin and prolactin secretion implications for fertility control.

Knowledge of the hypothalamic control of gonadotropin and prolactin release by the pituitary is reviewed. The anatomic areas which control gonadotropin and prolactin secretion include the medial preoptic area th rough the anterior hypothalamus to the medical basal hypothalamus for luteinizing hormone (LH) and median eminence/arcuate region for follicle stimulating hormone. The research leading to amino acid sequencing and localization of the releasing and inhibiting factors is described; the neurospecretory elements concerned with control of these hormones were limited to discrete areas of the preoptic area and hypothalamus. Other areas reviewed are the interaction of releasing factors with target gland hormones and synaptic transmitters involved in control of gonadotropin-releasing and inhibitory factors. Implications for control of fertility include: 1) bringing about ovulation in patients with a hypothalamic defect; 2) use of an anti-LH releasing factor for blocking ovulation; 3) artifical advancement of ovulation with a synthetic LH-rel easing factor; and 4) use of adrenergics - serotonin or melatonin - to b lock ovulation since gonadotropin and prolactin release are under adren ergic control.