ABSTRACT
To confirm recent in vitro findings, we examined the cardiovascular and electrocardiographic (ECG) effects of the dopamine receptor agonists ropinirole, apomorphine, and PNU-142774E in conscious dogs. Intravenous (i.v.) infusions of ropinirole totaling 20 microg/kg maximally reduced mean arterial pressure (MAP; -16 mm Hg) and the ECG PR interval (-13 milliseconds) and increased heart rate (HR; +29 b/min) and QTc length (+33 ms) at a peak plasma drug concentration (p[drug]) of 3.5 ng/ml. I.V. PNU-142774E was better tolerated through 66 microg/kg and a maximal p[drug] of 5.9 ng/ml with negligible cardiovascular changes and mild QTc reduction (13 ms). Apomorphine (25 microg/kg i.v.) was intermediate to ropinirole and PNU-142774E for emesis and peak changes in MAP (-6 mm Hg), HR (+24 b/min), and QTc (+15 milliseconds) at a mean p[drug] of 3.4 ng/ml. By comparison, the class III antiarrhythmic trecetilide (2.0 mg/kg bolus) increased QTc (+58 ms) without affecting mean arterial pressure or heart rate. This study establishes that in conscious dogs, the selective dopamine receptor agonist PNU-142774E has fewer cardiovascular and emetic effects than ropinirole and apomorphine and supports prior in vitro findings that ropinirole and apomorphine but not the PNU-142774E imidazoquinolin analog sumanirole reduces the delayed rectifier current in HERG transfected cells.
Subject(s)
Apomorphine/pharmacology , Blood Pressure/drug effects , Dopamine Agonists/pharmacology , Electrocardiography/drug effects , Heart Rate/drug effects , Imidazoles/pharmacology , Indoles/pharmacology , Quinolines/pharmacology , Receptors, Dopamine D2/agonists , Action Potentials/drug effects , Animals , Apomorphine/blood , Dogs , Drug Tolerance , Female , Imidazoles/blood , Indoles/blood , Quinolines/blood , Receptors, Dopamine D2/physiology , Receptors, Dopamine D3/physiologyABSTRACT
This chapter further affirms the safety and efficacy of hemi and total temporomandibular joint (TMJ) reconstruction with the Christensen TMJ Prostheses (TMJ Implants, Inc., Golden, CO, USA). Hemi and total TMJ reconstruction with the Christensen TMJ prostheses was first introduced by Robert W. Christensen, DDS in 1961 and 1965, respectively, and is gaining widespread acceptance as a viable alternative in the treatment of temporomandibular joint disorders (TMD). The Christensen TMJ devices have been used to treat various disorders in large numbers of patients, and the pertinent results of 10 years of study are reported in this chapter.
Subject(s)
Prostheses and Implants , Temporomandibular Joint/surgery , Chromium Alloys/therapeutic use , Humans , Pain Measurement , Prosthesis Design , Retrospective StudiesABSTRACT
Disc displacements develop from alterations in the structural integrity of the condyle-disc complex. A definitive treatment that may be considered for such derangements is surgical correction. The goal of surgery is to return the disc to normal functional relationship with the condyle, or replace the disc with an alloplast. Surgery, is, therefore, considered when conservative therapy fails to adequately resolve the symptoms, progression of the disorder occurs, or both.
