Studies on the hypotensive mechanisms of NZ-105, a new dihydropyridine derivative, in rats and rabbits.
1. Intravenous administration of NZ-105 caused a slow-onset and long-lasting hypotension in anesthetized SHR. 2. Centrally administered NZ-105 (0.04 mg/kg) slightly decreased blood pressure. 3. The hypotension of NZ-105 (0.1 mg/kg, i.v.) was not affected by atropine, propranolol, diphenhydramine plus cimetidine, aminophylline or indomethacin. 4. In ganglion-blocked rats, NZ-105 (0.003-0.3 mg/kg, i.v.) inhibited the pressor response to several hypertensive agents to a similar degree. 5. In pithed SHR, NZ-105 (0.03 mg/kg, i.v.) showed the same degree of hypotensive action as in non-treated SHR. 6. NZ-105 did not inhibit reflex responses to tilting in conscious rabbits. 7. Thus NZ-105 exerts its hypotensive action through the mechanisms of peripheral origin.
Shudo
C
C
Shiraoka Research Station of Biological Science, Nissan Chemical Industries Ltd., Saitama, Japan.
Masuda
Y
Y
Sakai
T
T
Tanaka
S
S
Shigenobu
K
K
Kasuya
Y
Y
D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects*; D003655:Decerebrate State; D004095:Dihydropyridines / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D009529:Nicardipine / Q000494:pharmacology; D009596:Nitrophenols; D009943:Organophosphorus Compounds / Q000008:administration & dosage / Q000494:pharmacology*; D011187:Posture; D011817:Rabbits; D051381:Rats; D011918:Rats, Inbred SHR; D017208:Rats, Wistar
D000959:Antihypertensive Agents; D004095:Dihydropyridines; D009596:Nitrophenols; D009943:Organophosphorus Compounds; C066425:efonidipine; D009529:Nicardipine