title: Role of vasopressin V(1a) and V2 receptors for the development of secondary brain damage after traumatic brain injury in mice.
abstract: Brain edema is still one of the most deleterious sequels of traumatic brain injury (TBI), and its pathophysiology is not sufficiently understood. The goal of the current study was to investigate the role of arginine vasopressin (AVP), also known as antidiuretic hormone (ADH), an important regulator of tissue water homeostasis, for the formation of post-traumatic brain edema, intracranial pressure (ICP), brain damage, and functional deficits following brain trauma. C57/B16 mice (n=112) were subjected to controlled cortical impact (CCI; 8m/s, 1 mm). At 3 min after trauma, animals received 500 ng of the AVP V(1a)-receptor antogonist (deamino-Pen(1), O-Me-Tyr(2), Arg(8)]-Vasopressin) or 500 ng of the AVP V2-receptor antagonist (adamantaneacetyl(1), O-Et-D-Tyr(2),Val(4), Abu(6),Arg(8,9)]-Vasopressin) by intracerebroventricular injection. After trauma, cerebral water content (24 h), ICP (24 h), contusion volume (24 h and 7 days), and functional outcome (1-7 days) were assessed (n=8 per experimental group). Post-traumatic inhibition of AVP V(1A) receptors reduced ICP by 29% (p < 0.05), brain water content by 45% (p < 0.05), and secondary contusion expansion by 37% (p < 0.05), and it significantly improved motor function 6 and 7 days after trauma (p < 0.05). Inhibition of AVP V2 receptors had no significant effect. The current results demonstrate that vasopressin V(1A) receptors are involved in the pathogenesis of brain edema formation and the subsequent development of secondary brain damage after traumatic brain injury. Accordingly, our study suggests that vasopressin V(1A) receptors may represent a novel therapeutic target for the treatment of post-traumatic brain edema and secondary brain damage.
authors.affiliation: Laboratory of Experimental Neurosurgery, Department of Neurosurgery & Institute for Surgical Research, University of Munich Medical Center-Grosshadern, Ludwig-Maximilians University, Munich, Germany.
authors.forename: Raimund
authors.initials: R
authors.lastname: Trabold
authors.forename: Sandro
authors.initials: S
authors.lastname: Krieg
authors.forename: Karsten
authors.initials: K
authors.lastname: Schöller
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Plesnila
mesh_terms: D000818:Animals; D065092:Antidiuretic Hormone Receptor Antagonists; D001127:Arginine Vasopressin / Q000502:physiology*; D001929:Brain Edema / Q000209:etiology*; D001930:Brain Injuries / Q000150:complications* / Q000188:drug therapy / Q000473:pathology*; D019586:Intracranial Hypertension / Q000209:etiology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009043:Motor Activity; D017483:Receptors, Vasopressin / Q000502:physiology*; D020127:Recovery of Function
chemical_list: D065092:Antidiuretic Hormone Receptor Antagonists; D017483:Receptors, Vasopressin; D001127:Arginine Vasopressin