Hypothalamic dopamine system

According to this scheme, the major difference between male and female odor effects is that the hypothalamic dopamine system is inhibited by female odors instead of activated, as described for male odors. Therefore, the converse... 

Dopamine agonists decrease pituitary prolactin secretion through a dopamine-mimetic action on the pituitary at two central nervous system loci (1) they decrease dopamine turnover in the tuberoinfundibular neurons of the arcuate nucleus, generating increased hypothalamic dopamine and (2) they act directly on pituitary dopamine receptors to inhibit prolactin release. 

Fig. 4. Proposed stages of recovery from the profound regulatory impairments induced by lateral hypothalamic lesions, based on Teitelbaum and Epstein (1972). A similar profile of recovery is seen from the impairments induced by selective bilateral lesions of forebrain dopamine systems (see text).

Ungerstedt U (1970) Is interruption of the nigro-striatal dopamine system producing the lateral hypothalamic syndrome Acta Physiol Sccmd 80 35A-36A. 

Andersson K, Fuxe K, Eneroth P, Agnati L, Locatelli V (1980) Hypothalamic dopamine and noradrenaline nerve terminal systems and their reactivity to changes in pituitary-thyroid and pituitary-adrenal activity and to prolactin. In Brambilla F, Racagna G, de Wied D (Eds), Prog. Psychoneuroendocrinol. pp. 395 406. Elsevier, Amsterdam. 

Kawano H, Daikoku S (1987) Functional topography of the rat hypothalamic dopamine neuron systems. Retrograde tracing and immunohistochemical study. J Comp Neurol 265 242-253. 

Less common etiologies include central nervous system lesions that physically compress the pituitary stalk and interrupt tonic hypothalamic dopamine secretion, resulting in hyperprolactinemia. Increased thyroid-releasing hormone (TRH) concentrations in hypothyroidism can stimulate prolactin secretion and cause hyperprolactinemia. During conditions of renal or liver compromise, the... 

The intermediate length systems include the tuberoinfundibular system, which projects from the arcuate and periventricular nuclei into the intermediate lobe of the pituitary and the median eminence. This system is responsible for the regulation of such hormones as prolactin. The inter hypothalamic neurons send projections to the dorsal and posterior hypothalamus, the lateral septal nuclei and the medullary periventricular group, which are linked to the dorsal motor nucleus of the vagus such projections may play a role in the effects of dopamine on the autonomic nervous system. 

In addition to being synthesized in the peripheral nervous system, dopamine is synthesized in the corpus striatum and in the mesocortical, mesolimbic, and tuberoinfundibular systems. Norepinephrine is synthesized and stored primarily in sympathetic noradrenergic nerve terminals, as well as in the brain and the adrenal medulla. Epinephrine is synthesized and stored primarily in the adrenal medulla and, to a certain extent, in the hypothalamic nuclei. 

The brain and the immune system are accepted as the two major body s adaptive systems (Elenkov et al., 2000). The brain can modulate immune functions and the immune system also sends messages to the brain. The communication between these two systems is done mainly by the hypothalamic-pituitary-adrenal axis and the autonomic nervous system (ANS). The sympathetic nervous system (SNS), which is part of the ANS, innervates the lymphoid organs (Elenkov et al., 2000) (Flierl et al., 2007). Catecholamines, like dopamine, serotonin, epinephrine and norepinephrine, are the end products of the SNS. 

Andersson K, Fuxe K, Eneroth P, Isaksson O, Nyberg F, Roos P (1983) Rat growth hormone and hypothalamic catecholamine nerve terminal systems. Evidence for rapid and discrete reductions in dopamine and noradrenaline levels and turnover in the median eminence of the hypophysectomized male rat. Eur J Pharmacol 95 271-275. 

Lindvall O, Bjorklund A, Skagerberg G (1984) Selective histochemical demonstration of dopamine terminal systems in rat di- and telencephalon new evidence for dopaminergic innervation of hypothalamic neurosecretory nuclei. Brain Res 306 19-30. 

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