Peptide immunoreactive neurons in the amygdala and the bed nucleus of the stria terminalis project to the midbrain central gray in the rat

• Published in: Peptides (New York, N.Y. : 1980) Vol. 13; no. 3; pp. 451 - 460
• Main Authors: Gray, Thackery S., Magnuson, Debra J.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.05.1992; Elsevier Science
• Subjects: Amygdala - anatomy & histology; Animals; Biological and medical sciences; Central nervous system; Central neurotransmission. Neuromudulation. Pathways and receptors; Corticotropin releasing factor; Corticotropin-Releasing Hormone - isolation & purification; Enkephalins - isolation & purification; Fluorescent Antibody Technique; Fundamental and applied biological sciences. Psychology; Immunocytochemistry; Immunohistochemistry - methods; Male; Neurons - chemistry; Neuropeptides - isolation & purification; Neurotensin; Neurotensin - isolation & purification; Periaqueductal Gray - anatomy & histology; Prosencephalon - anatomy & histology; Rats; Retrograde tracing; Somatostatin; Somatostatin - isolation & purification; Substance P; Substance P - isolation & purification; Thalamus - anatomy & histology; Vertebrates: nervous system and sense organs; Retrograde tracing; Neurotensin; Somatostatin; Substance P; Immunocytochemistry; Corticotropin releasing factor; Rat; Rodentia; ACTH-RH; Central nervous system; Basal ganglion; Neuropeptide; Vertebrata; Mammalia; Amygdaloid nucleus; Brain (vertebrata); Bed nucleus stria terminalis
• ISSN: 0196-9781; 1873-5169
• DOI: 10.1016/0196-9781(92)90074-D

The central nucleus of the amygdala, bed nucleus of the stria terminalis, and central gray are important components of the neural circuitry responsible for autonomic and behavioral responses to threatening or stressful stimuli. Neurons of the amygdala and bed nucleus of the stria terminalis that project to the midbrain central gray were tested for the presence of peptide immunoreactivity. To accomplish this aim, a combined immunohistochemical and retrograde tracing technique was used. Maximal retrograde labeling was observed in the amygdala and bed nucleus of the stria terminalis after injections of retrograde tracer into the caudal ventrolateral midbrain central gray. The majority of the retrogradely labeled neurons in the amygdala were located in the medial central nucleus, although many neurons were also observed in the lateral subdividion of the central nucleus. Most of the retrogradely labeled neurons in the BST were located in the ventral and posterior lateral subdivisions, although cells were also observed in most other subdivisions. Retrogradely labeled neurotensin, corticotropin releasing factor (CRF), and somatostatin neurons were mainly observed in the lateral central nucleus and the dorsal lateral BST. Retrogradely labeled substance P-immunoreactive cells were found in the medial central nucleus and the posterior and ventral lateral BST. Enkephalin-immunoreactive retrogradely labeled cells were not observed in the amygdala or bed nucleus of the stria terminalis. A few cells in the hypothalamus (paraventricular and lateral hypothalamic nuclei) that project to the central gray also contained CRF and neurotensin immunoreactivity. The results suggest the amygdala and the bed nucleus of the stria terminalis are a major forebrain source of CRF, neurotensin, somatostatin, and substance P terminals in the midbrain central gray.