Abstract
This study describes a novel method for direct subarachnoid drug delivery to the medullary dorsal horn region of rats, without introducing a catheter. The reliability of the method was demonstrated by a pharmacological validation; that is, morphine administration to the medullary region blocked the nociceptive response to formalin injected in the temporomandibular joint (TMJ) region, an effect that was prevented by co-administration of naloxone. The method proposed offers many advantages over the existing methods for medullary drug delivery with catheter implantation. It is easy to be employed, it does not induce any sign of motor impairment, and it does not require the neck surgery performed to implant a catheter in the medullary dorsal horn region. Therefore, it is a useful method for subarachnoid drug delivery in behavioral trigeminal pain studies, particularly when nociceptive behavioral measures that require normal neck muscle activity to occur, such as head withdraw or head flinch, are evaluated.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Analgesics, Opioid / administration & dosage
-
Animals
-
Arthralgia / chemically induced
-
Arthralgia / drug therapy
-
Arthralgia / physiopathology
-
Drug Delivery Systems / instrumentation
-
Drug Delivery Systems / methods*
-
Head Movements / drug effects
-
Head Movements / physiology
-
Male
-
Medulla Oblongata / drug effects
-
Medulla Oblongata / physiology
-
Medulla Oblongata / surgery*
-
Microinjections / instrumentation
-
Microinjections / methods*
-
Morphine / administration & dosage*
-
Naloxone / pharmacology
-
Narcotic Antagonists / pharmacology
-
Neck Muscles / drug effects
-
Neck Muscles / physiology
-
Neurosurgical Procedures / instrumentation
-
Neurosurgical Procedures / methods
-
Nociceptors / physiology
-
Pain Measurement
-
Rats
-
Rats, Wistar
-
Subarachnoid Space / anatomy & histology
-
Subarachnoid Space / physiology
-
Subarachnoid Space / surgery*
-
Syringes / standards
-
Temporomandibular Joint Disorders / chemically induced
-
Temporomandibular Joint Disorders / drug therapy
-
Temporomandibular Joint Disorders / physiopathology
-
Trigeminal Caudal Nucleus / drug effects
-
Trigeminal Caudal Nucleus / physiology
-
Trigeminal Caudal Nucleus / surgery
Substances
-
Analgesics, Opioid
-
Narcotic Antagonists
-
Naloxone
-
Morphine