Pituitary aminopeptidase activities involved in blood-pressure regulation are modified by dietary cholesterol: sex differences.
Given that the existence of a local renin-angiotensin system (RAS) in the pituitary and its participation in the regulation of blood pressure and other biological functions are widely accepted, the aim of this work is to analyze the influence of dietary cholesterol on the activity of the enzymes involved in the metabolism of the effector peptides of the renin-angiotensin system (angiotensin II and III) and vasopressin, in the pituitary of male and female mice fed on a cholesterol-enriched diet (1% cholesterol and 0.5% cholic acid). Soluble and membrane-bound pituitary aminopeptidase A (aspartyl- and glutamyl-aminopeptidase), aminopeptidase M (alanyl-aminopeptidase), aminopeptidase B (arginyl-aminopeptidase) and cystinyl-aminopeptidase activities were fluorimetrically measured. In female mice, cholesterol-enriched diet produced a significant increase in soluble aspartyl- and membrane-bound aspartyl- and glutamyl-aminopeptidase activities, and a significant decrease in membrane-bound alanyl-, arginyl- and cystinyl-aminopeptidase activities. In male mice, after feeding the diet, a significant increase in soluble glutamyl- and membrane-bound arginyl-aminopeptidase activities was observed. Our results indicate differential effects of dietary cholesterol on the metabolism of angiotensin II and III and vasopressin in the pituitary of male and female mice.
Ramírez-Expósito
M J
MJ
Unit of Physiology, Department of Health Sciences, Faculty of Experimental and Health Sciences, University of Jaén, Paraje Las Lagunillas s/n E-23071, Jaén, Spain. mramirez@ujaen.es
Mayas
M D
MD
García
M J
MJ
Ramírez
M
M
Martínez-Martos
J M
JM
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D002784:Cholesterol / Q000097:blood; D002791:Cholesterol, Dietary / Q000494:pharmacology*; D010122:Cystinyl Aminopeptidase / Q000378:metabolism*; D005260:Female; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D010902:Pituitary Gland / Q000187:drug effects / Q000201:enzymology*; D012727:Sex Characteristics; D012995:Solubility
D002791:Cholesterol, Dietary; D008565:Membrane Proteins; D002784:Cholesterol; D010122:Cystinyl Aminopeptidase