Dopamine transporter mRNA is increased in the CNS of Zucker fatty (fa/fa) rats

• Published in: Brain research bulletin Vol. 46; no. 3; pp. 199 - 202
• Main Authors: Figlewicz, Dianne P, Patterson, Terrell A, Johnson, Laura Beth, Zavosh, Aryana, Israel, Paige A, Szot, Patricia
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.06.1998; Elsevier Science
• Subjects: Animals; Biological and medical sciences; Brain - metabolism; Carrier Proteins - genetics; Dopamine Plasma Membrane Transport Proteins; Female; In situ hybridization; Medical sciences; Membrane Glycoproteins; Membrane Transport Proteins; Metabolic diseases; Nerve Tissue Proteins; Neurotransmitter transporters; Obesity; Obesity - genetics; Obesity - metabolism; Rats; Rats, Zucker - genetics; Rats, Zucker - metabolism; RNA, Messenger - metabolism; Tyrosine 3-Monooxygenase - genetics; Zucker rats; In situ hybridization; Zucker rats; Neurotransmitter transporters; Obesity; Vertebrata; Mammalia; Dopamine; Rat; Animal; Rodentia; Neurotransmitter; Catecholamine; Gene expression; Carrier protein
• ISSN: 0361-9230; 1873-2747
• DOI: 10.1016/S0361-9230(98)00009-4

The obese Zucker fa/fa rat is characterized by hyperinsulinemia, obesity, and altered monoamine metabolism in the central nervous system (CNS). It has been proposed that the changes in monoamine metabolism may contribute to the metabolic pathophysiology of these animals. Because it has been reported that insulin may regulate the catecholamine reuptake transporters, which terminate monoaminergic synaptic signaling, in the present study we tested whether messenger ribonucleic acid (mRNA) levels for the noradrenergic (NE) or dopaminergic (DA) transporters were altered in obese fa/fa vs. lean Fa/Fa Zucker rats. We found significantly elevated DA transporter levels in both the ventral tegmental area/substantia nigra pars compacta (VTA/SNc) and zona incerta (ZI) of obese Zucker fa/fa rats (164 ± 24% of control levels, p = .024; and 316 ± 61% of control levels, p = .019, respectively). Measurement of mRNA for tyrosine hydroxylase (TH), the rate-limiting enzyme for NE and DA synthesis revealed no effect of the fa gene in either NE or DA neurons. These findings suggest that increased DA clearance, and perhaps decreased DA signaling, may occur in the obese Zucker fa/fa rat.