Regional distribution of a creatine transporter in rat auditory brainstem: an in-situ hybridization study

• Published in: Hearing research 1996-09, Vol.98 (1), p.29-37
• Main Authors: Hiel, Hakim, Happe, H.Kevin, Warr, W.Bruce, Morley, Barbara J.
• Format: Article
• Language: English
• Subjects: Animals; Auditory Cortex - metabolism; Base Sequence; Biological and medical sciences; Biological Transport; Brain Stem - metabolism; Carrier Proteins - genetics; Carrier Proteins - metabolism; Central auditory system; Cochlear Nucleus - diagnostic imaging; Cochlear Nucleus - metabolism; Creatine - metabolism; Creatine transporter; Ear and associated structures. Auditory pathways and centers. Hearing. Vocal organ. Phonation. Sound production. Echolocation; Fundamental and applied biological sciences. Psychology; High-energy phosphate metabolism; Image Processing, Computer-Assisted; In Situ Hybridization; Inferior Colliculi - diagnostic imaging; Inferior Colliculi - metabolism; Isotope Labeling; Male; Membrane Transport Proteins; Molecular Sequence Data; Oligonucleotide Probes; Olivary Nucleus - diagnostic imaging; Olivary Nucleus - metabolism; Phosphates - metabolism; Radiography; Rats; Rats, Sprague-Dawley; RNA, Messenger - metabolism; Staining and Labeling; Vertebrates: nervous system and sense organs
• ISSN: 0378-5955; 1878-5891
• DOI: 10.1016/0378-5955(96)00046-9

The expression of an mRNA encoding a creatine transporter (CRT1) was investigated in the rat auditory system under ambient sound conditions, using radiolabeled and non-radiolabeled oligonucleotide in-situ hybridization. The results indicated that CRT1 mRNA is widely distributed in auditory nuclei, including the fusiform and deep layers of the dorsal cochlear nucleus, the ventral cochlear nucleus, the superior olivary complex, the nuclei of the lateral lemniscus and the inferior colliculus. The molecular layer of the dorsal cochlear nucleus and the medial geniculate have low levels of label. Creatine provides cells with a reservoir of high-energy phosphate. Neurons do not synthesize creatine but accumulate it by a transport mechanism, which is probably the limiting step in the regulation of intracellular creatine. Therefore, the quantity of transporter expressed may reflect the utilization of creatine and could serve as an in-vitro indicator of endogenous high-energy metabolism in some cells. Although most auditory nuclei express CRT1 mRNA, the quantity of CRTI mRNA varies among auditory nuclei, indicating that many auditory nuclei have high and fluctuating energy requirements. The level of CRT1 transcript or protein may be regulated by chronic metabolic changes in the auditory system that may occur, for example, with damage to the acoustic organ or the aging process.