title: Strain differences in rat brain epinephrine synthesis: regulation of alpha-adrenergic receptor number by epinephrine.
abstract: Inbred tht strains Fischer 344 (F344) and Buffalo (BUF) differ in serveral physiological and behavioral measures. It was found that the activity of adrenomedullary and regional brain phenylethanolamine N-methyltransferase is at least four times higher in F344 rats than in BUF rats; these strain-dependent differences corresponded directly with the epinephrine content of the medulla-pons and hypothalamus. Conversely, alpha-adrenergic receptor density in brain regions containing phenylethanolamine N-methyltransferase is two to three times lower in F344 rats than in BUF rats; alpha-receptors in frontal cortex (a brain region lacking phenylethanolamine N-methyltransferase activity and epinephrine) are similar in both strains. These findings suggest that strain-dependent differences in alpha-receptors are regulated by inherited differences in presynaptic adrenergic neuronal function in different brain regions.
mesh_terms: D000313:Adrenal Medulla / Q000201:enzymology; D000818:Animals; D001921:Brain / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D002540:Cerebral Cortex / Q000201:enzymology; D004837:Epinephrine / Q000502:physiology*; D005260:Female; D007031:Hypothalamus / Q000201:enzymology; D008526:Medulla Oblongata / Q000201:enzymology; D010625:Phenylethanolamine N-Methyltransferase / Q000378:metabolism; D011149:Pons / Q000201:enzymology; D051381:Rats; D011919:Rats, Inbred Strains / Q000378:metabolism*; D011941:Receptors, Adrenergic / Q000378:metabolism*; D011942:Receptors, Adrenergic, alpha / Q000378:metabolism*; D013045:Species Specificity
chemical_list: D011941:Receptors, Adrenergic; D011942:Receptors, Adrenergic, alpha; D010625:Phenylethanolamine N-Methyltransferase; D004837:Epinephrine