Autoradiographic localization of subtypes of angiotensin II antagonist binding in the rat brain

摘要: The non-peptide angiotensin II receptor compounds DuP 753 and WL 19 were utilized to detect subtypes of [125I]Sar1-Ile8-angiotensin binding receptors in the rat brain. In forebrain homogenates, produced a partial displacement with displacing approximately 65% 35% binding. Using techniques quantitative autoradiography, distinct regional distribution antagonist bind was detected. II-1 site (the subtype preferentially displaced by 753) appeared predominate dipsogenic, cardiovascular endocrine areas, including subfornical organ, paraventricular periventricular nuclei hypothalamus, anterior pituitary, dorsal motor nucleus vagus, solitary tract area postrema. Additional areas that contained predominantly ventral hippocampus, substantia gelatinosa trigeminal nucleus, lateral olfactory tract, piriform cortex median preoptic nucleus. II-2 (displaced 19) predominant thalamus, inferior olive, septum, subthalamic locus coeruleus, medial geniculate amygdala. Several brain contain both subtypes, superior colliculi, bulb. concentrated involved mediating effects on drinking, status blood pressure. Localization sites thalamus which process sensory information suggests novel modulatory role for at this subtype. These results indicate are highly selective that, general these compartmentalized regions. used studies should provide excellent tools discern functional