Faculty Collaboration Database

Selective forebrain fiber tract lesions implicate ventral hippocampal structures in tonic regulation of paraventricular nucleus corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP) mRNA expression. Brain Res 1992 Oct 02;592(1-2):228-38

Date

10/02/1992

Pubmed ID

1333341

DOI

10.1016/0006-8993(92)91680-d

Scopus ID

2-s2.0-0026731199 (requires institutional sign-in at Scopus site)   124 Citations

Abstract

The hippocampus appears to be involved in tonic regulation of the hypothalamo-pituitary-adrenocortical axis via interactions with corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP)-containing neurons of the hypothalamic paraventricular nucleus (PVN). To further investigate the anatomical basis of such interactions, lesions were made to forebrain fiber tracts in position to communicate inhibitory information from the hippocampus to the PVN. Total fimbria-fornix transections (TFF) and lateral fimbria-fornix lesions (LFF) both significantly increased CRH mRNA levels in the medial parvocellular PVN, as assayed by semi-quantitative in situ hybridization histochemistry. Medial fimbria-fornix lesions or section of the medial corticohypothalamic tracts (MCHT) did not influence CRH mRNA levels. The LFF group showed increases in both AVP mRNA and ACTH secretion, whereas no other lesion was effective in this regard. The results suggest: (1) hippocampal efferents conferring tonic inhibition of the HPA axis probably originate in regions contributing to the lateral extent of the fornix, representing structures in the ventral subiculum and ventral extent of CA1; (2) projections from the hippocampus to the medial basal hypothalamus (travelling in the MCHT) are unlikely to affect HPA function; (3) hippocampus may influence the PVN CRH/AVP neuron at multiple levels, in that LFF and TFF lesions have differential effects on PVN AVP mRNA levels and ACTH secretion.

Author List

Herman JP, Cullinan WE, Young EA, Akil H, Watson SJ

Author

William E. Cullinan PhD Adjunct Associate Professor in the Neurosurgery department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adrenocorticotropic Hormone
Animals
Arginine Vasopressin
Corticotropin-Releasing Hormone
Densitometry
Hippocampus
Male
Nerve Fibers
Nucleic Acid Hybridization
Paraventricular Hypothalamic Nucleus
Prosencephalon
RNA, Messenger
Radioimmunoassay
Rats
Rats, Sprague-Dawley