Protein gene product (PGP) 9.5 immunoreactivity in nerve fibres and pinealocytes of guinea-pig pineal gland: interrelationship with tyrosine- hydroxylase- and neuropeptide-Y-immunoreactive nerve fibres.
This light-microscopic (LM) immunohistochemical study has evaluated the presence and distribution of the pan-neural and neuroendocrine marker protein gene product (PGP) 9.5 in pinealocytes and nerve fibres of guinea-pig pineal gland. The pattern of PGP 9.5-immunoreactive (ir) nerve fibres has been compared with that of fibres staining for tyrosine hydroxylase (TH) or neuropeptide Y (NPY). The vast majority of pinealocytes stained for PGP 9.5, although with variable intensity. PGP 9.5 immunoreactivity was localized in pinealocytic cell bodies and processes. Double-immunofluorescence revealed that PGP 9.5 immunoreactivity was absent from glial cells identified with a monoclonal antibody against glial fibrillary acidic protein (GFAP). PGP 9.5 immunoreactivity was also present in a large number of nerve fibres and varicosities distributed throughout the pineal gland. The number of TH-ir and NPY-ir nerve fibres was lower compared with those containing PGP 9.5 immunoreactivity. All fibres staining for NPY also stained for TH. NPY-ir nerve fibres were found to be much more numerous than previously reported for this species. The double-immunofluorescence analysis indicated that almost all TH-ir nerve fibres of the pineal gland contained PGP 9.5 immunoreactivity. However, few PGP 9.5-ir nerve fibres, located in the periphery and the central part of the gland, were TH-negative. A large number of PGP 9.5-ir fibres was concentrated in the pineal stalk. In contrast, TH-ir and NPY-ir nerve fibres were rare in this part of the pineal gland. Our data provide evidence that immunohistochemistry for PGP 9.5 may be a useful tool further to differentiate central and peripheral origins of pineal innervation.(ABSTRACT TRUNCATED AT 250 WORDS)
Romeo
H E
HE
Anatomisches Institut, Johannes Gutenberg-Universität, Mainz, Germany.
Weihe
E
E
Müller
S
S
Vollrath
L
L
D000818:Animals; D006168:Guinea Pigs; D007150:Immunohistochemistry; D008297:Male; D009412:Nerve Fibers / Q000378:metabolism; D009478:Neuropeptide Y / Q000378:metabolism; D010870:Pineal Gland / Q000166:cytology / Q000294:innervation / Q000378:metabolism*; D013869:Thiolester Hydrolases / Q000378:metabolism*; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism; D043222:Ubiquitin Thiolesterase
D009478:Neuropeptide Y; D014446:Tyrosine 3-Monooxygenase; D013869:Thiolester Hydrolases; D043222:Ubiquitin Thiolesterase