Abstract
Somatostatin-immunoreactive perikarya in the periventricular anterior hypothalamus were demonstrated to be surrounded by gamma aminobutyric acid GABA-immunoreactive nerve terminals, by combining pre-embedding im-munocytochemistry for somatostatin and gold labelling post-embedding immunocytochemistry for GAB A. Ultrastructural studies revealed that in each 100-nm section, cells immunoreactive for somatostatin (n = 62) were contacted by a mean of 7.6 ±0.4 terminal profiles of which 3.0 ±0.3 (40%) were GABA-immunoreactive. Most GABA-immunoreactive terminals contained clear rounded vesicles and, where synaptic specializations were well demonstrated, appeared to be symmetric. The finding provides evidence that there is a significant GABA input to somatostatin neurons, an observation strengthening the hypothesis that GABA may inhibit somatostatin neurons, thereby causing increased secretion of growth hormone.
Original language | English |
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Pages (from-to) | 268-872 |
Number of pages | 605 |
Journal | Neuroendocrinology |
Volume | 46 |
Issue number | 3 |
DOIs | |
Publication status | Published - 1987 |
Keywords
- Anterior hypothalamus
- Gamma aminobutyric acid
- Growth hormone
- Immunocytochemistry
- Somatostatin