Abstract
Experiments were conducted to test if blockade of GABAA receptors in the dorsomedial hypothalamic nucleus (DMH) of rats, which is known to elicit cardiovascular and anxiety responses, would also elicit changes in the plasma levels of adrenocorticotrophic hormone (ACTH) and corticosterone. Male Sprague-Dawley rats were anesthetized with pentobarbital, fitted with femoral arterial catheters and implanted with microinjection cannulae into the DMH or the sites anterior to the DMH (i.e., closer to the paraventricular nucleus (PVN) of the hypothalamus). The rats were then injected with either artificial cerebrospinal fluid (aCSF; 100 nl) or the GABAA antagonist, bicuculline methiodide (BMI; 50 pmol in 100 nl) and their plasma samples obtained at 5, 30, 60, and 120 min after microinjection. Plasma ACTH and corticosterone were measured by using a radioimmunoassay. Rats injected with BMI, but not aCSF, into the DMH showed significant increases in heart rate (HR, 110 +/- 16 beats/min), blood pressure (BP; 30 +/- 4 mmHg), and plasma levels of both ACTH (64 +/- 10 pg/ml) and corticosterone (170 +/- 25 ng/ml) from baseline. BMI injections into the anterior sites closer to the PVN did not elicit significant increases in HR, BP, or plasma lev...Continue Reading
Citations
Dec 9, 2003·American Journal of Physiology. Regulatory, Integrative and Comparative Physiology·Scott B EvansDianne P Figlewicz
Aug 8, 2001·Journal of Neuroendocrinology·M P JohnsonM Chamberlain
Dec 22, 2000·American Journal of Physiology. Regulatory, Integrative and Comparative Physiology·T W Bailey, J A Dimicco
Mar 12, 2003·Neuropsychopharmacology : Official Publication of the American College of Neuropsychopharmacology·Holger KittnerPeter Illes
Oct 5, 2010·Experimental Physiology·Edson Alexandre QueirozAndréa Siqueira Haibara
Aug 7, 2012·Journal of Neuroendocrinology·K EbnerN Singewald
Jun 16, 2015·Frontiers in Systems Neuroscience·Joel D Hahn, Larry W Swanson
Jun 16, 2015·PloS One·Sherin Al-SafadiShimon Amir
Apr 11, 2001·American Journal of Physiology. Regulatory, Integrative and Comparative Physiology·S M MorinJ A DiMicco
Oct 23, 2018·Toxicology and Industrial Health·Nawal A AhmedNoha A Salama
Jan 28, 2009·The Journal of Physiology·Rodrigo C A de MenezesJoseph A DiMicco
Apr 23, 2008·Current Protocols in Neuroscience·Tammy J SajdykAnantha Shekhar
Jul 25, 2000·Baillière's Best Practice & Research. Clinical Endocrinology & Metabolism·D S Jessop
Aug 21, 2003·Progress in Neurobiology·Mark J Millan
Sep 20, 2006·Progress in Neurobiology·Norman PecoraroSusan F Akana
Jun 24, 2010·Brain Research Bulletin·Leandro Marques de Souza, Celso Rodrigues Franci
Sep 3, 2009·Brain Research Bulletin·Young-Jun SeoHong-Won Suh