Dudás B, Merchenthaler I. Catecholaminergic axons innervate LH-releasing hormone immunoreactive neurons of the human diencephalon.
J Clin Endocrinol Metab 2001;
86:5620-6. [PMID:
11701744 DOI:
10.1210/jcem.86.11.8023]
[Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Catecholamines have been shown to modulate gonadal functions via interactions with hypothalamic LH-releasing hormone (LHRH)-synthesizing neurons. To reveal the morphological background of this phenomenon, the distribution of LHRH neurons and tyrosine hydroxylase (TH)-immunoreactive (IR), catecholaminergic structures were mapped in the human diencephalon. First, the location of LHRH and TH-IR neuronal elements was analyzed, and then the relationship between the two different systems was examined. The LHRH-IR cell bodies were mainly present in the medial preoptic and infundibular areas. The TH-IR perikarya were located in the periventricular, paraventricular, and supraoptic hypothalamic nuclei and also in the median eminence. The TH-IR fibers were numerous in septal, infundibular, periventricular, and lateral hypothalamic regions. The brown, diaminobenzidine-labeled LHRH-containing perikarya were found to receive black, silver-intensified, TH-positive axon terminals in the infundibular and medial preoptic areas. However, in the preoptic and caudal parts of the diencephalon, only a few juxtapositions were noted. The present results indicate that hormone released from diencephalic LHRH-IR neurons in humans may be influenced by the central catecholaminergic system via direct synaptic mechanisms.
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