text: The animals were divided into thirteen groups (n=4 each) receiving an i.v. bolus injection of, either physiological saline (0.3 ml/kg; control), or the antagonists << SB224289 >> (300 microg/kg; [[ 5-HT1B ]]), BRL15572 (300 microg/kg; 5-HT1D), rauwolscine (300 microg/kg; alpha2), SB224289 + BRL15572 (300 microg/kg each), SB224289 + rauwolscine (300 microg/kg each), BRL15572 + rauwolscine (300 microg/kg each), rauwolscine (300 microg/kg) + prazosin (100 microg/kg; alpha1), SB224289 (300 microg/kg) + prazosin (100 microg/kg), SB224289 (300 microg/kg) + rauwolscine (300 microg/kg) + prazosin (100 microg/kg), SB224289 (300 microg/kg) + prazosin (100 microg/kg) + BRL44408 (1,000 microg/kg; alpha2A), SB224289 (300 microg/kg) + prazosin (100 microg/kg)+ imiloxan (1,000 microg/kg; alpha2B), or SB224289 (300 microg/kg) + prazosin (100 microg/kg) + MK912 (300 microg/kg; alpha2C).