Effects of the new calcium antagonist 2-nitratopropyl 3-nitratopropyl 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate on cerebral circulation in cats.
Effects of CD-349 (2-nitratopropyl 3-nitratopropyl 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate) on cerebral circulation were studied in 10 cats. The cats were fixed in a stereotactic head-holder, and two burr holes were made at 3-mm intervals over the left parietal cortex. Through one cranial window, the pial artery and vein diameters were measured continuously by a newly developed videocamera system in conjunction with a width analyzer, and the other one was used for measurement of cerebral blood volume (CBV). The pial artery (141 +/- 14 micron) was dilated by 16.6 +/- 4.9% (p less than 0.01) 1 min and 24.8 +/- 5.1% (p less than 0.01) 5 min after the CD-349 injection. The pial vein (101 +/- 20 micron) was also dilated with the percent increase of the diameter being 11.4 +/- 4.0% (p less than 0.01) 1 min and 11.3 +/- 4.9% (p less than 0.05) 5 min after the CD-349 administration. The CBV was also increased. The mean arterial blood pressure was decreased by 39.8 +/- 7.3 mmHg (p less than 0.01) 1 min and 34.4 +/- 5.5 mmHg (p less than 0.01) 5 min after drug injection. Thereafter, the blood pressure gradually returned to the pre-drug level. Form these results it is suggested that CD-349 exerts direct vasodilatory action via inhibition of calcium influx across vascular cell membranes into cerebral vessels.
Kawamura
J
J
Department of Neurology, School of Medicine, Keio University, Tokyo, Japan.
Gotoh
F
F
Fukuuchi
Y
Y
Amano
T
T
Tanaka
K
K
Uematsu
D
D
Suzuki
N
N
Kobari
M
M
Obara
K
K
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D002415:Cats; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D004095:Dihydropyridines / Q000494:pharmacology*; D005260:Female; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects
D002121:Calcium Channel Blockers; D004095:Dihydropyridines; C054179:CD 349