Jastrow.H.1, S. Lohfink-Schumm2, H.A. Burda3 and H.A. Oelschläger2
1 Department of Anatomy, J. Gutenberg-University, Becherweg
13, D-55128 Mainz.
2 Dept Anat. J.W. Goethe-Univ., Theod. Stern-Kai 7, D-60590
Frankfurt a.M.,
3 Dept Zool. Univ. Essen, Universitätsstr. 2, D-45117
Essen, Germany.
Investigated six neonate, juvenile and non-reproductive adult specimens
(4f, 2m) of the African mole rat (Cryptomys spec.) by cryotomy and
immunocytochemistry.
In these animals, some variability is found with respect to the number
of ,,genuine" LHRH-ir neurons (see below). The terminalis nerve (n.t.)
comprised 104-239 neurons (average: 162) while in the central nervous system
there were 351-964 LHRHir neurons (average: 540). In most cases, there
was good correspondence between the left and right side 85 to the number
of neurons in the n.t. and brain. The majority of the LHRHir neurons were
bipolar (average of 74% in the n.t. and of 80% in the CNS) while the rest
were irregular in shape.- In three specimens, an additional LHRH- immunoreactivity
was found In so called ,,dark spot (DS) cells in the parafascicular nucleus
(range: 661-1113; average: 836) in the form of 1-3 heavily labelled vacuoles
of different size. These vacuoles seem to be restricted to adult non-reproductive
animals. The identity of these ,,spot cells so far has not been determined.
During the postnatal period, the amount of LHRH-ir material does not
show a developmental trend; with the exception of the DS cells, the number
of genuine LHRH-ir cells and fibres seems to be more or less constant from
the neonate to the adult stage. The DS cells are not found in adult reproductive
animals (females); here, the vacuoles are no longer detectable.