TRH axon terminals in synapsis with GRF neurons in the arcuate nucleus of the rat hypothalamus as revealed by double labeling immunocytochemistry.
Synaptic input to neurons containing growth hormone-releasing factor (GRF) by axon terminals containing thyrotropin-releasing hormone (TRH) in the arcuate nucleus (AN) of the rat hypothalamus was examined using a method combining pre-embedding peroxidase-anti-peroxidase for GRF with postembedding immunocolloidal gold staining for TRH. The TRH-like immunoreactive axon terminals were found to make synaptic contact with GRF-like immunoreactive neurons with unlabeled axon terminals. From these findings, TRH-containing neurons in the hypothalamic AN of the rat may be considered to innervate GRF neurons, to regulate GRF secretion or to have some other functions via synapses.
D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000502:physiology*; D001369:Axons / Q000378:metabolism / Q000502:physiology*; D013007:Growth Hormone-Releasing Hormone / Q000502:physiology*; D006651:Histocytochemistry; D007120:Immunochemistry; D008297:Male; D009411:Nerve Endings / Q000378:metabolism / Q000502:physiology*; D009474:Neurons / Q000378:metabolism / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D013569:Synapses / Q000502:physiology*; D013973:Thyrotropin-Releasing Hormone / Q000502:physiology*
D013973:Thyrotropin-Releasing Hormone; D013007:Growth Hormone-Releasing Hormone