title: The difference between nicardipine and its enantiomers on inhibiting vasoconstriction of isolated rabbit thoracic artery.
abstract: The present study was designed to study the difference effects between nicardipine and its two enantiomers on thoracic artery of rabbit. A high-performance liquid chromatographic method was used to prepare the two enantiomers of nicardipine. The thoracic artery of rabbit was removed. The vessels were cut into 3 mm in width and 15 mm in length spiral strips and immersed into tissue baths. The concentration-response curves of nicardipine and its enantiomers were obtained by cumulative administration of the vasoconstrictors. Nicardipine and the enantiomers could shift the dose-response curves of NE, KCl or CaCl2 to right in a nonparallel manner and decrease the maximum effective in a concentration-depended manner, respectively. The pD2' value of R-(-)-nicardipine showed significantly effective than that of nicardipine and S-(+)-nicardipine (P<0.01). There was not obviouse difference between the pD2' value of nicardipine and S-(+)-nicardipine (P>0.05). The results demonstrate that the stereoselective interaction between R-(-)-nicardipine and L-calcium channel receptor is more stronger than that of S-(+)-nicardipine.
authors.affiliation: College of Pharmacy, Xi'an Jiaotong University, Xi'an 710061, China.
authors.forename: Sicen
authors.initials: S
authors.lastname: Wang
authors.forename: Langchong
authors.initials: L
authors.lastname: He
authors.forename: Bofeng
authors.initials: B
authors.lastname: Yun
mesh_terms: D000818:Animals; D000959:Antihypertensive Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D002121:Calcium Channel Blockers / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D003864:Depression, Chemical; D005260:Female; D066298:In Vitro Techniques; D008297:Male; D009529:Nicardipine / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D011817:Rabbits; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D013895:Thoracic Arteries / Q000187:drug effects* / Q000502:physiology; D014661:Vasoconstriction / Q000187:drug effects*
chemical_list: D000959:Antihypertensive Agents; D002121:Calcium Channel Blockers; D009529:Nicardipine