NMDA Receptor and NO Mediate ET-1-Induced Behavioral and Cardiovascular Effects in Periaqueductal Gray Matter of Rats

  • Ryu, Jung-Su (Department of Pharmacology, College of Pharmacy., Chung Ang University and Department of Pharmacology, College of medicine, Soonchunhyang University) ;
  • Shin, Chang-Yell (Department of Pharmacology, College of Pharmacy., Chung Ang University and Department of Pharmacology, College of medicine, Soonchunhyang University) ;
  • Yang, Sung-Jun (Department of Pharmacology, College of Pharmacy., Chung Ang University and Department of Pharmacology, College of medicine, Soonchunhyang University) ;
  • Lee, Tai-Sang (Department of Pharmacology, College of Pharmacy., Chung Ang University and Department of Pharmacology, College of medicine, Soonchunhyang University) ;
  • La, Hyun-O (Department of Pharmacology, College of Pharmacy., Chung Ang University and Department of Pharmacology, College of medicine, Soonchunhyang University) ;
  • Song, Hyun-Ju (Department of Pharmacology, College of Pharmacy., Chung Ang University and Department of Pharmacology, College of medicine, Soonchunhyang University) ;
  • Yom, Yoon-Ki (Department of Pharmacology, College of Pharmacy., Chung Ang University and Department of Pharmacology, College of medicine, Soonchunhyang University) ;
  • Huh, In-Hoi (Department of Pharmacology, College of Pharmacy., Chung Ang University and Department of Pharmacology, College of medicine, Soonchunhyang University) ;
  • Sohn, Uy-Dong (Department of Pharmacology, College of Pharmacy., Chung Ang University and Department of Pharmacology, College of medicine, Soonchunhyang University)
  • Published : 2001.02.01

Abstract

Endothelin-1 (ET-1 ), a novel and potent vasoconstrictor in blood vessel, is known to have some functions in the rat central nervous system (CNS), In order to investigate the central functions of ET-1 , ET-1 was administered to the periaqueductal gray area (PAC) of anesthetized rats to induce barrel rolling and increase the arterial blood pressure (ABP). ET-1 had a modulatory effect on central cardiovascular and behavioral control. The selective N-methyl-D-aspartate (NMDA) receptor antagonist MK-801 (3${u}m/ol/kg$, i.p.) blocked the ET-1 induced responses, and both the nitric oxide synthase (NOS) inhibitor L-NAME (N-nitro-L-arginine mIThyl-ester 1 nmol/rat) and the nitric oxide (NO) scavenger hemoglobin (15 nmol/rat) had similar effects in redtAcing the IT-1 (10 pmol/rat)-induced behavioral changes and ABP elevation. However, NO donor sodium nitroprusside (SNP 10${u}g$, 1${u}g/rat$) decreased the ET-1 induced ABP elevation, and recovered the ET-1 -induced barrel rolling effect that was reduced by MK-801. These results suggest that ET-1 might have neuromodulatory functions such as ABP elevation and barrel rolling induction in the PAG of the rats via the NMDA receptor and NO.

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