Measurement of catechol-O-methyltransferase activity in the brain of Dahl salt-sensitive rats.
Metabolism by catechol-O-methyltransferase (COMT) is one of the inactivation pathways of catecholamines (CAs), which are important hormones in regulating blood pressure both in central and in peripheral sympathetic nerve endings. We have reported the rapid determination method of COMT activity using high-performance liquid chromatography (HPLC)-fluorescence detection. In the present study, we applied the method to brain tissues, cerebral cortex, cerebellum, hypophysis and hypothalamus. COMT activities were assessed by measuring normetanephrine with the use of norepinephrine as an endogenous substrate. We examined the COMT activities in the brains of Dahl salt-sensitive (DS) rats given normal-salt or high-salt diet for 13 weeks, and found that membrane-bound COMT activities in the cerebral cortex were significantly reduced in high-salt loaded DS rats compared with normal-salt loaded DS rats.
Hirano
Yoko
Y
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan.
Tsunoda
Makoto
M
Shimosawa
Tatsuo
T
Fujita
Toshiro
T
Funatsu
Takashi
T
D000818:Animals; D001921:Brain / Q000201:enzymology* / Q000378:metabolism; D002394:Catechol O-Methyltransferase / Q000378:metabolism*; D002395:Catecholamines / Q000378:metabolism* / Q000502:physiology; D004195:Disease Models, Animal; D006973:Hypertension / Q000503:physiopathology; D008297:Male; D009638:Norepinephrine / Q000378:metabolism; D009647:Normetanephrine / Q000032:analysis; D051381:Rats; D020303:Rats, Inbred Dahl; D012965:Sodium Chloride / Q000009:adverse effects / Q000494:pharmacology
D002395:Catecholamines; D009647:Normetanephrine; D012965:Sodium Chloride; D002394:Catechol O-Methyltransferase; D009638:Norepinephrine