[The pulsatile LH fluctuation (spiking) dependent on the circulating prolactin. Studies during physiological (puerperium), functional pathological and TRH induced hyperprolactinemia].
The magnitude and frequency of episodic LH-fluctuations have been observed to change during the different phases of the menstrual cycle. A hypothalamic control center appears to be responsible for these variations. Disturbances of the hypothalamus often make themselves known through a lack of LH-episodes. Ahypothalamic derangement in women with functional amenorrhoea can result in a disregulation of gonadotropins as well as prolactin, thereby leading to hyperprolactinemia. One finds an inverse relationship between high prolactin secretion and cessation of or decreased pulsatile LH-secretion (spiking). LH-spiking was tested in physiological post partum, functional pathological and TRH-induced hyperprolactinemias. No LH-episodes were observed post partum after the end of HCG clearance although prolactin had returned to normal levels at 12 days p.p. The mode of LH-secretion in a group of functionally amenorrhoic patients was changed by a TRH-induced prolactin increase: the previously observed LH-spikes in these women could no longer be seen. Normal cycling women, however, were not affected. In patients with hyperprolactinemic anovulatory syndromes, prolactin suppressed LH-fluctuations reappeared after administration of 2-Bromo-alpha-ergocryptin. The inhibitory influence of hyperprolactinemia on the function of the gonadostat will be discussed. High plasma prolactin levels influence the cyclic and tonic hypothalamic function. Furthermore, prolactin appears to have a peripheral inhibitory influence on ovarian gonadotropin stimulation. Post partum anovulation and amenorrhoea can be caused by an antigonadotropic and antigonadic effect of prolactin.
D000568:Amenorrhea / Q000378:metabolism; D005260:Female; D006801:Humans; D007031:Hypothalamus / Q000502:physiology; D007774:Lactation; D007986:Luteinizing Hormone / Q000378:metabolism*; D049590:Postpartum Period; D011247:Pregnancy; D011388:Prolactin / Q000097:blood*; D013973:Thyrotropin-Releasing Hormone / Q000502:physiology
D013973:Thyrotropin-Releasing Hormone; D011388:Prolactin; D007986:Luteinizing Hormone
Die pulsatile LH-Fluktuation (Spiking) in Abhängigkeit vom zirkulierenden Prolaktin Untersuchungen bei physiologischer (Pureperium), bei funktionell pathologischer sowie unter TRH induzierter Hyperprolaktinaemie