Increased sensitivity of neurons to angiotensin II in SHR as compared to WKY rats.
Angiotensin II (ANG II)-sensitive septal neurons in the brain of stroke-prone spontaneously hypertensive rats (SHR-sp) and of normotensive Wistar-Kyoto rats (WKY) were investigated for possible differences at receptor sites. ANG II, the competitive ANG II-antagonist saralasin, and acetylcholine (ACh), were applied microiontophoretically onto neurons of the lateral septal area. ANG II-evoked neuronal firing which was specifically inhibited by saralasin occurred at a significant lower threshold in SHR-sp (23%) and showed an extended postactivity (340%) as compared to the age-matched WKY controls. In contrast, the activity due to ACh remained similar in both strains.
D000109:Acetylcholine / Q000494:pharmacology; D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D005071:Evoked Potentials / Q000187:drug effects; D006973:Hypertension / Q000503:physiopathology*; D008297:Male; D009474:Neurons / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D011945:Receptors, Angiotensin / Q000187:drug effects*; D011956:Receptors, Cell Surface / Q000187:drug effects*; D012688:Septum Pellucidum / Q000187:drug effects*
D011945:Receptors, Angiotensin; D011956:Receptors, Cell Surface; D000804:Angiotensin II; D000109:Acetylcholine