title: Acute stress stimulates 3H-inositol phosphates accumulation in rat cerebral cortex. An in vivo determination.
abstract: Using an in vivo method, we examined the effects of acute stress on rat brain inositol phosphates (IPs) levels. Cerebral phosphoinositides were prelabeled with 3H-myoinositol injected i.c.v. 24 h prior to a 15 min forced swimming stress. The stressful condition resulted in a 35% increase in whole brain 3H-IPs content, mainly due to an enhancement in cerebral cortical 3H-IPs accumulation. Cerebellar and brain minus cortex levels of 3H-IPs showed no alteration in stressed animals. Among the IPs, stress induced a 102% and 92% increase in the cerebral cortical content of 3H-IP and 3H-IP2 respectively. Pretreatment of animals with diazepam (2 mg/kg, i.p.) prevented the stress-induced 3H-IPs increase, in both the whole brain and the cerebral cortex. Diazepam administration alone did not produce changes in 3H-IPs. These results suggest that an acute stress condition stimulates in vivo the brain IPs turnover, probably because of an enhanced receptor-linked hydrolysis of phosphoinositides.
authors.affiliation: Institute of Cellular Biology, Faculty of Medicine, University of Buenos Aires, Argentina.
authors.forename: S
authors.initials: S
authors.lastname: Raskovsky
authors.forename: J H
authors.initials: JH
authors.lastname: Medina
mesh_terms: D000818:Animals; D001143:Arousal / Q000187:drug effects / Q000502:physiology*; D002540:Cerebral Cortex / Q000187:drug effects / Q000502:physiology*; D003975:Diazepam / Q000494:pharmacology; D006868:Hydrolysis; D007295:Inositol Phosphates / Q000378:metabolism*; D008297:Male; D010716:Phosphatidylinositols / Q000378:metabolism; D011292:Premedication; D051381:Rats; D017208:Rats, Wistar; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology*
chemical_list: D007295:Inositol Phosphates; D010716:Phosphatidylinositols; D003975:Diazepam