InVitro Down Regulation and Possible Internalization of Central Angiotensin Receptors
Angiotensin receptors in peripheral tissues have been shown to up or down regulate in response to changes in circulating angiotensin2/3. Nevertheless it has been difficult to demonstrate changes in central angiotensin receptors in response to alterations in blood or cerebral spinal fluid (CSF) levels of angiotensins4/5. Failure to detect such changes could be the result of a dilution effect whereby only a small percentage of angiotensin receptors are exposed to altered ligand levels or a rapidly recycling population of receptors. This study demonstrates that tachyphalaxis does occur to intracerebroventricularly (ICV) applied angiotensins. This change in angiotensin sensitivity may be a result of receptor down regulation and internalization which appear to occur at least in the in vitro preparation used in this study.
KeywordsCerebral Spinal Fluid Receptor Internalization Glomerulosa Zone Tissue Treatment Drinking Response
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