TY - JOUR ID - 48102 TI - Central Nucleus of Amygdala Mediate Pressor Response Elicited by Microinjection of Angiotensin II into the Parvocellular Paraventricular Nucleus in Rats JO - Iranian Journal of Medical Sciences JA - IJMS LA - en SN - 0253-0716 AU - Rostami, Bahar AU - Hatam, Masoumeh AD - Department of Physiology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran Y1 - 2022 PY - 2022 VL - 47 IS - 3 SP - 272 EP - 279 KW - Angiotensin II KW - Paraventricular hypothalamic nucleus KW - Amygdala KW - Blood pressure DO - 10.30476/ijms.2021.90015.2080 N2 - Background: The Paraventricular Hypothalamic Nucleus (PVN) coordinates autonomic and neuroendocrine systems to maintain homeostasis. Microinjection of angiotensin II (AngII) into the PVN has been previously shown to produce pressor and bradycardia responses. Anatomical evidence has indicated that a substantial proportion of PVN neurons is connected with the neurons in the central amygdala (CeA). The present study aimed to examine the possible contribution of the CeA in cardiovascular responses evoked by microinjection of AngII into the parvocellular portion of PVN (PVNp) before and after microinjection of cobalt chloride (CoCl2) into the CeA.Methods: The experiments were conducted at the Department of Physiology of Shiraz University of Medical Sciences, from April 2019 to November 2019. There were two groups of 21 eight-week-old urethane anesthetized male rats, namely saline (n=9 rats) and AngII (n=12 rats) groups. Drugs (100 nL) were microinjected via a single-glass micropipette into the PVNp and CeA. Their blood pressure (BP) and heart rate (HR) were recorded throughout the experiments. The mean arterial pressure (MAP) and heart rate (HR) were compared to the pre-injection values using paired t test, and to those of the saline group using independent t test.Results: Microinjection of AngII into the PVNp produced pressor response (p <0.0001) with no significant changes in HR (P=0.70). Blockade of CeA with CoCl2 attenuated the pressor response to microinjection of AngII into the PVNp (p <0.001).Conclusion: In the PVNp, Ang II increased the rats’ blood pressure. This response was in part mediated by the CeA. Our study suggested that these two nuclei cooperate to perform their cardiovascular functions. UR - https://ijms.sums.ac.ir/article_48102.html L1 - https://ijms.sums.ac.ir/article_48102_703278458846160900a878234bbe77ce.pdf ER -