Dural neuropeptide changes after subarachnoid hemorrhage in rats

• Published in: Brain research bulletin Vol. 31; no. 6; pp. 713 - 718
• Main Authors: Keller, Jeffrey T., Mullen, Bradley G., Zuccarello, Mario
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 1993; Elsevier Science
• Subjects: Animals; Biological and medical sciences; Cell Count; Dura mater; Dura Mater - metabolism; Dura Mater - pathology; Immunohistochemistry; Male; Mast Cells - pathology; Medical sciences; Nerve Fibers - pathology; Neurology; Neuropeptides; Neuropeptides - metabolism; Rat; Rats; Rats, Sprague-Dawley; Subarachnoid hemorrhage; Subarachnoid Hemorrhage - metabolism; Subarachnoid Hemorrhage - pathology; Vascular diseases and vascular malformations of the nervous system; Dura mater; Neuropeptides; Rat; Subarachnoid hemorrhage; Neuropeptide Y; Nervous system diseases; Serotonin; Substance P; Rodentia; Cardiovascular disease; Calcitonine gene related peptide; Cerebral meninge; Neuropeptide; Hemorrhage; Vertebrata; Experimental disease; Mammalia; Animal; Subarachnoid; Mast cell; Cerebrovascular disease
• ISSN: 0361-9230; 1873-2747
• DOI: 10.1016/0361-9230(93)90146-3

The effect of subarachnoid hemorrhage (SAH) on the neuropeptides and mast cells of the rat dura mater has not been reported. We examined the outcome of SAH on the rat supratentorial dura mater to determine whether durai nerves undergo effects similar to those of nerves accompanying cerebral blood vessels after SAH. Following the injection of fresh autologous arterial blood into the cisterna magna, animals were sacrificed at 6, 24, and 48 h, and 6 days post-SAH. Dural whole mounts were immunohistochemically reacted with antibodies to calcitonin gene-related peptide (CGRP), substance P (SP), neuropeptide Y (NPY), and serotonin (5-HT). SP-like immunostaining was substantially reduced after SAH and subsequently returned to control levels at 6 days. NPY-like fiber innervation of the dura was markedly reduced after SAH; although immunostaining intensity increased, it had not returned to control levels at 6 days. The 5-HT content of dural mast cells identified by immunostaining markedly decreased at 6 and 24 h and returned to control levels at 48 h. In contrast, CGRP immunostaining was unchanged in all experimental groups. One possible explanation for this differential response is that sub-populations of trigeminovascular neurons containing SP, CGRP, or CGRP and SP respond differently to various stimuli, including SAH. Another possibility is a differential release of SP or CGRP from the same fiber. To the best of our knowledge this is the first documentation that the dura is also a target for intracranial pathological processes, such as SAH. Because the dura mater contains a well-represented neuropeptidergic innervation similar to the perivascular innervation of the major vessels at the base of the brain, the dura may serve as a model to understand central neural responses following pure intracranial pathological events.