The isolated spinal cord-skin preparation of the newborn rat and effects of some algogenic and analgesic substances.
We have developed an isolated spinal cord-skin preparation of the newborn rat. The spinal cord together with a piece of skin connected to the cord by the saphenous nerve was isolated from 1- to 4-day-old rats and separately superfused with artificial cerebrospinal fluid in two neighbouring chambers. Potentials were recorded extracellularly from the third lumbar ventral root. Application of capsaicin (0.5-2 microM) or KCl (60-350 mM) with brief pressure pulses to the perfusion bath of the skin evoked a depolarizing response of 20- to 40-s duration in the ventral root. The response was depressed by [Met5]enkephalin (0.03-3 microM), morphine (0.1-2 microM) and a tachykinin antagonist, [D-Arg1,D-Trp7,9,Leu11] substance P (spantide), (1-10 microM), applied to the spinal cord by superfusion, whereas the response was augmented by centrally administered calcitonin gene-related peptide (0.1-0.2 microM) or bicuculline (0.5-1 microM).
Yanagisawa
M
M
Department of Pharmacology, Faculty of Medicine, Tokyo Medical and Dental University, Japan.
Hosoki
R
R
Otsuka
M
M
D000200:Action Potentials / Q000187:drug effects; D000700:Analgesics / Q000494:pharmacology*; D000818:Animals; D000831:Animals, Newborn; D001640:Bicuculline / Q000494:pharmacology; D015740:Calcitonin Gene-Related Peptide / Q000494:pharmacology; D002211:Capsaicin / Q000494:pharmacology*; D002555:Cerebrospinal Fluid / Q000502:physiology; D004744:Enkephalin, Methionine / Q000494:pharmacology; D009020:Morphine / Q000494:pharmacology; D011189:Potassium Chloride / Q000494:pharmacology*; D011458:Prostaglandins E / Q000494:pharmacology; D051381:Rats; D012867:Skin / Q000294:innervation*; D013004:Somatostatin / Q000494:pharmacology; D013116:Spinal Cord / Q000187:drug effects* / Q000502:physiology; D013373:Substance P / Q000031:analogs & derivatives / Q000494:pharmacology
D000700:Analgesics; D011458:Prostaglandins E; D013373:Substance P; D013004:Somatostatin; D004744:Enkephalin, Methionine; D011189:Potassium Chloride; D009020:Morphine; C042867:spantide; D015740:Calcitonin Gene-Related Peptide; D002211:Capsaicin; D001640:Bicuculline