Biomaterial Database

Nitric oxide synthase activity in the dorsal periaqueductal gray of rats expressing innate fear responses. 1998

S Chiavegatto, and C Scavone, and N S Canteras

Department of Pharmacology, Biomedical Sciences Institute, University of Sao Paulo, Brazil.

Immunohistochemical studies have shown nitric oxide synthase (NOS)-positive neurons in the dorsolateral sector of periaqueductal gray (PAG), a neural site known to be critical for the expression of defensive responses. In the present study, we first characterized the dorsal PAG (dPAG) NOS, and then examined NOS activity and cyclic GMP (cGMP) accumulation in the dPAG of rats exposed to a predator (cat) for 15 min. NOS activity evaluated by enzymatic conversion of [3H]arginine to [3H]citrulline in dPAG of exposed rats increased 14.6% and the cGMP radioimmunoassay showed an increase of 30.6% in relation to non-exposed rats. These results suggest an involvement of the NO/cGMP pathway in the dPAG during defensive responses.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009043	Motor Activity	Body movements of a human or an animal as a behavioral phenomenon.	Activities, Motor,Activity, Motor,Motor Activities
D010487	Periaqueductal Gray	Central gray matter surrounding the CEREBRAL AQUEDUCT in the MESENCEPHALON. Physiologically it is probably involved in RAGE reactions, the LORDOSIS REFLEX; FEEDING responses, bladder tonus, and pain.	Mesencephalic Central Gray,Midbrain Central Gray,Central Gray Substance of Midbrain,Central Periaqueductal Gray,Griseum Centrale,Griseum Centrale Mesencephali,Periaqueductal Gray Matter,Substantia Grisea Centralis,Substantia Grisea Centralis Mesencephali,Central Gray, Mesencephalic,Central Gray, Midbrain,Gray Matter, Periaqueductal,Gray, Central Periaqueductal,Griseum Centrale Mesencephalus,Periaqueductal Grays, Central
D011235	Predatory Behavior	Instinctual behavior pattern in which food is obtained by killing and consuming other species.	Predation,Behavior, Predatory,Predatory Behaviors
D011336	Probability	The study of chance processes or the relative frequency characterizing a chance process.	Probabilities
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D002531	Cerebellum	The part of brain that lies behind the BRAIN STEM in the posterior base of skull (CRANIAL FOSSA, POSTERIOR). It is also known as the "little brain" with convolutions similar to those of CEREBRAL CORTEX, inner white matter, and deep cerebellar nuclei. Its function is to coordinate voluntary movements, maintain balance, and learn motor skills.	Cerebella,Corpus Cerebelli,Parencephalon,Cerebellums,Parencephalons
D003600	Cytosol	Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.	Cytosols
D004924	Escape Reaction	Innate response elicited by sensory stimuli associated with a threatening situation, or actual confrontation with an enemy.	Flight Reaction,Escape Reactions,Flight Reactions,Reaction, Escape,Reaction, Flight,Reactions, Escape,Reactions, Flight
D005106	Exploratory Behavior	The tendency to explore or investigate a novel environment. It is considered a motivation not clearly distinguishable from curiosity.	Curiosity,Novelty-Seeking Behavior,Behavior, Exploratory,Behavior, Novelty-Seeking,Behaviors, Exploratory,Behaviors, Novelty-Seeking,Curiosities,Exploratory Behaviors,Novelty Seeking Behavior,Novelty-Seeking Behaviors