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.
Drug Delivery Research Center, School of Pharmacy and Pharmaceutical Sciences, Purdue University, West Lafayette, Indiana 47907.
R J
RJ
Erb
L M
LM
Her
A
A
Abdallah
A K
AK
Mitra
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