Angiotensin-converting enzyme blockade by Captopril changes angiotensin II receptors and angiotensinogen concentrations in the brain of SHR-sp and WKY rats.
Angiotensin II-sensitive neurons in the brain of spontaneously hypertensive rats (SHR-sp) and of Wistar Kyoto rats (WKY) treated with the angiotensin-converting enzyme inhibitor Captopril were investigated for possible differences at receptor sites. Furthermore, the concentrations of angiotensinogen and renin were measured in different brain regions of these animals by biochemical assay. The higher receptor sensitivity of septal neurons to angiotensin II which existed in SHR-sp as compared to WKY was diminished by Captopril. Angiotensinogen concentrations were lower in the anterior hypothalamus but not in the septum of SHR-sp as compared to WKY. Captopril increased the level in both strains. Renin concentrations did not differ in SHR-sp and WKY. Chronic treatment with Captopril induced an increase of about 20% in septum and hypothalamic regions of SHR-sp and WKY rats. Whether these changes are causally linked to the hypertension in SHR-sp remains to be investigated.
D000109:Acetylcholine / Q000494:pharmacology; D000804:Angiotensin II / Q000494:pharmacology; D000806:Angiotensin-Converting Enzyme Inhibitors; D000808:Angiotensinogen / Q000378:metabolism*; D000809:Angiotensins / Q000378:metabolism*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D001921:Brain / Q000187:drug effects* / Q000201:enzymology; D002216:Captopril / Q000494:pharmacology*; D007032:Hypothalamus, Anterior / Q000187:drug effects; D011392:Proline / Q000031:analogs & derivatives*; D051381:Rats; D011919:Rats, Inbred Strains; D011945:Receptors, Angiotensin / Q000187:drug effects*; D011956:Receptors, Cell Surface / Q000187:drug effects*; D012083:Renin / Q000378:metabolism; D012688:Septum Pellucidum / Q000187:drug effects
D000806:Angiotensin-Converting Enzyme Inhibitors; D000809:Angiotensins; D011945:Receptors, Angiotensin; D011956:Receptors, Cell Surface; D000808:Angiotensinogen; D000804:Angiotensin II; D011392:Proline; D002216:Captopril; D012083:Renin; D000109:Acetylcholine