Pharmacodynamics and biophasic drug levels of methionine enkephalin.
Methionine enkephalin (Met-E) is a naturally occurring pentapeptide. It appears to mediate pain perception by blocking CNS pathways. Using rabbits, a log dose relationship was obtained between Met-E-induced dilation of the pupil (mydriasis) and constant intravenous infusion dose rates (14, 20, 28, 37, 56, 73, and 129 micrograms/min/kg). Steady-state dilation is reached within 9 min. Dose-effect curves (DEC) were fitted by a linear regression analysis of the log dose versus percentage dilation plots. Fitted DEC were used to determine temporal profiles for the relative biophasic drug level.
Erb
R J
RJ
Drug Delivery Research Center, School of Pharmacy and Pharmaceutical Sciences, Purdue University, West Lafayette, Indiana 47907.
Her
L M
LM
Abdallah
A
A
Mitra
A K
AK
D000818:Animals; D004305:Dose-Response Relationship, Drug; D004744:Enkephalin, Methionine / Q000493:pharmacokinetics* / Q000494:pharmacology; D007262:Infusions, Intravenous; D011680:Pupil / Q000187:drug effects; D011817:Rabbits; D012044:Regression Analysis
D004744:Enkephalin, Methionine