Distribution of GABA-like immunoreactivity in the central nervous system of the cockroach, Periplaneta americana (L.).
Gamma-aminobutyric acid (GABA) is one of the most frequently occurring neurotransmitters in the central nervous system. Using an antiserum against a GABA-protein conjugate, this has also been demonstrated for insects. The distribution of GABA-like immunoreactive neuronal elements within the central nervous system of the insect Periplaneta americana has been investigated by means of immunocytochemistry. An overview of the distribution of neuronal elements with GABA-like immunoreactivity (GLIR) in the brain is given. The ventral nerve cord was extensively investigated. The highest number of neurons with GLIR was estimated in the metathoracic ganglion (ca. 1000). The function of the suboesophageal ganglion as an inhibitory centre for the central nervous system was further confirmed by the high number of GABAergic elements and descending GABAergic pathways within the ventral nerve cord. A GABAergic innervation of skeletal musculature by so-called common inhibitory neurons was revealed for the legs of cockroaches. Nevertheless, GABA mainly seems to be a neurotransmitter in central interneurons. Identical distribution patterns of neuronal elements after immunofluorescence double-staining with anti-GABA antibodies and antibodies against the GABA-synthesizing enzyme glutamic acid decarboxylase demonstrated the high specificity of the anti-GABA serum used in this paper.
Blechschmidt
K
K
Department of Animal Physiology, Friedrich-Schiller-University Jena, GDR.
Eckert
M
M
Penzlin
H
H
D000818:Animals; D002490:Central Nervous System / Q000378:metabolism*; D003058:Cockroaches / Q000378:metabolism*; D005724:Ganglia / Q000378:metabolism; D007150:Immunohistochemistry; D010526:Periplaneta; D005680:gamma-Aminobutyric Acid / Q000032:analysis*
D005680:gamma-Aminobutyric Acid