Co-localization of substance P and Met-enkephalin-Arg6-Gly7-Leu8 in the intraspinal neurons of the rat, with special reference to the neurons in the substantia gelatinosa.
A double-labeling immunofluorescence technique was employed to investigate the co-localization of the functionally antagonistic neuropeptides, substance P and enkephalins, within intraspinal neurons of the rat. Anti-Met-enkephalin-Arg6-Gly7-Leu8 (Enk-8) antiserum was used as a marker of the preproenkephalin A neuron system. The observations were focused on the lumbar spinal cord. Co-localization was most prominent within neurons in the substantia gelatinosa, in which more than 95% of substance P-like immunoreactivity neurons showed Enk-8-like immunoreactivity. These double-labeled cells corresponded to 45% of Enk-8-like immunoreactive neurons in the same area. This suggests that SP/Enk-8 interaction occurs at the axon terminals of the substantia gelatinosa neurons. In deeper layers of the dorsal horn (laminae III, IV), only 14% and 6% of SP-like immunoreactive and Enk-8-like immunoreactive neurons were double labeled, respectively. Co-localization was also observed in neurons located in the laminae I, V, VII and X, suggesting concomitant involvement of these peptides in a variety of spinal cord functions.
Senba
E
E
Department of Anatomy (II), Osaka University Medical School, Japan.
Yanaihara
C
C
Yanaihara
N
N
Tohyama
M
M
D000818:Animals; D004744:Enkephalin, Methionine / Q000031:analogs & derivatives* / Q000032:analysis; D007150:Immunohistochemistry; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013116:Spinal Cord / Q000032:analysis*; D013373:Substance P / Q000032:analysis*
D013373:Substance P; D004744:Enkephalin, Methionine; C033453:enkephalin-Met, Arg(6)-Gly(7)-Leu(8)-