Funktionelle Anatomie des Hypothalamus

In this neuroanatomical overview the main nuclear areas of the hypothalamus are presented with special emphasis on the hormonal control of gynecological functions. The nuclei in the periventricular zone primarily regulate the endocrine system, while the nuclei in the medial and lateral zones regulate autonomic and somatic behavior. These areas connect through the dorsal longitudinal fasciculus to the brainstem, through the medial forebrain bundle to the cerebral cortex, through the fornix to the hippocampus, through the stria terminalis to the amygdala, through the mammillothalamic tract to the thalamus, and through the median eminence to the pituitary gland. The latter is particularly relevant and regulated by various tuberoinfundibular neurons, which have numerous synaptic connections with local interneurons that determine the thresholds for the release of hypophysiotropic substances in response to hormonal feedback signals. Moreover, novel aspects of the regulation of oxytocin and prolactin release are discussed. In fact, high circulating levels of prolactin are not only facilitated by the suppression of dopaminergic neurons in the arcuate nucleus but also by increased expression of prolactin-releasing factors in tuberoinfundibular neurons.