Biomaterial Database

Biphasic alteration in the trigeminal nociceptive neuronal responses after intracerebroventricular injection of prostaglandin E2 in rats. 1997

T Oka, and M Hosoi, and K Oka, and T Hori

Department of Physiology, Faculty of Medicine, Kyushu University, Fukuoka, Japan.

To investigate the role of prostaglandin E2 (PGE2) in the brain in nociception electrophysiologically, we injected PGE2 (0.1 fmol(-1) nmol) into the lateral cerebroventricle (LCV) of anesthetized rats and observed the changes of the responses of the wide dynamic range (WDR) neurons in the trigeminal nucleus caudalis to noxious pinching of facial skin. The LCV injection of PGE2 at 1 fmol and 10 fmol enhanced the responses of the majority of WDR neurons to noxious stimuli, whereas that of PGE2 at 100 pmol and 1 nmol suppressed them. The enhancement and suppression of the nociceptive responses of WDR neurons were observed 15-25 min and 5-15 min after injection of PGE2 at 10 fmol (3.53 pg) and 1 nmol (353 ng), respectively. On the other hand, the LCV injection of PGE2 at both 10 fmol and 1 nmol had no effect on the responses of the low threshold mechanoreceptive neurons to skin brushing. These results provide electrophysiological evidence that brain-derived PGE2 has biphasic effects on nociception, i.e., it induces mechanical hyperalgesia at lower doses and hypoalgesia at higher doses in rats.

UI	MeSH Term	Description	Entries
D007276	Injections, Intraventricular	Injections into the cerebral ventricles.	Intraventricular Injections,Injection, Intraventricular,Intraventricular Injection
D008297	Male		Males
D009474	Neurons	The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.	Nerve Cells,Cell, Nerve,Cells, Nerve,Nerve Cell,Neuron
D010146	Pain	An unpleasant sensation induced by noxious stimuli which are detected by NERVE ENDINGS of NOCICEPTIVE NEURONS.	Suffering, Physical,Ache,Pain, Burning,Pain, Crushing,Pain, Migratory,Pain, Radiating,Pain, Splitting,Aches,Burning Pain,Burning Pains,Crushing Pain,Crushing Pains,Migratory Pain,Migratory Pains,Pains, Burning,Pains, Crushing,Pains, Migratory,Pains, Radiating,Pains, Splitting,Physical Suffering,Physical Sufferings,Radiating Pain,Radiating Pains,Splitting Pain,Splitting Pains,Sufferings, Physical
D011458	Prostaglandins E	(11 alpha,13E,15S)-11,15-Dihydroxy-9-oxoprost-13-en-1-oic acid (PGE(1)); (5Z,11 alpha,13E,15S)-11,15-dihydroxy-9-oxoprosta-5,13-dien-1-oic acid (PGE(2)); and (5Z,11 alpha,13E,15S,17Z)-11,15-dihydroxy-9-oxoprosta-5,13,17-trien-1-oic acid (PGE(3)). Three of the six naturally occurring prostaglandins. They are considered primary in that no one is derived from another in living organisms. Originally isolated from sheep seminal fluid and vesicles, they are found in many organs and tissues and play a major role in mediating various physiological activities.	PGE
D002552	Cerebral Ventricles	Four CSF-filled (see CEREBROSPINAL FLUID) cavities within the cerebral hemispheres (LATERAL VENTRICLES), in the midline (THIRD VENTRICLE) and within the PONS and MEDULLA OBLONGATA (FOURTH VENTRICLE).	Foramen of Monro,Cerebral Ventricular System,Cerebral Ventricle,Cerebral Ventricular Systems,Monro Foramen,System, Cerebral Ventricular,Systems, Cerebral Ventricular,Ventricle, Cerebral,Ventricles, Cerebral,Ventricular System, Cerebral,Ventricular Systems, Cerebral
D000204	Activity Cycles	Bouts of physical irritability or movement alternating with periods of quiescence. It includes biochemical activity and hormonal activity which may be cellular. These cycles are shorter than 24 hours and include sleep-wakefulness cycles and the periodic activation of the digestive system.	Activity Cycle,Cycle, Activity,Cycles, Activity
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012867	Skin	The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor