Increased adrenal catecholamines in salt-sensitive genetically hypertensive Dahl rats.
Catecholamine levels and activity of catecholamine-forming enzymes have been quantitated in adrenal glands of Dahl sodium-resistant (R) and sodium-sensitive (S), genetically hypertensive rats maintained on low- or high-salt diets. A high-salt diet results in markedly different changes in the catecholamine metabolism in R and S rats. In R rats, a high-salt diet reduces the activities of tyrosine 3-hydroxylase (TH;-5%) and dopamine beta-hydroxylase (DBH; -18%) as well as the levels of all catecholamines (dopamine -28%, norepinephrine -11%, and epinephrine -28%). In contrast, S rats fed a high-salt diet showed increased TH (+7%) and phenylethanolamine N-methyltransferase (+16%) activities as well as an increased content of adrenal norepinephrine (+13%) and epinephrine (+21%). These findings demonstrate a genetic difference in the effects of a high-salt diet on the synthesis of catecholamines in the adrenal gland of Dahl R and S rats. Hypertension only occurs in S rats on a high-salt diet, concomitant with large increases in the formation of adrenal catecholamines.
D000302:Adrenal Cortex / Q000503:physiopathology*; D000313:Adrenal Medulla / Q000503:physiopathology*; D000818:Animals; D001794:Blood Pressure; D001835:Body Weight; D002395:Catecholamines / Q000378:metabolism*; D004039:Diet, Sodium-Restricted; D004299:Dopamine beta-Hydroxylase / Q000378:metabolism; D006973:Hypertension / Q000235:genetics / Q000503:physiopathology*; D008297:Male; D009929:Organ Size; D010625:Phenylethanolamine N-Methyltransferase / Q000378:metabolism; D051381:Rats; D011922:Rats, Mutant Strains; D012965:Sodium Chloride / Q000494:pharmacology; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
D002395:Catecholamines; D012965:Sodium Chloride; D014446:Tyrosine 3-Monooxygenase; D004299:Dopamine beta-Hydroxylase; D010625:Phenylethanolamine N-Methyltransferase