Biomaterial Database

Excitatory and inhibitory actions of intrathecally administered 5-hydroxytryptamine on sympathetic nerve activity in the rat. 1988

A P Yusof, and J H Coote

Department of Physiology, Medical School, University of Birmingham, U.K.

In chloralose/urethane anaesthetised rats the effect of intrathecal (i.t.) administration of 5-hydroxytryptamine (5-HT) on activity in sympathetic nerves to the kidney was studied. Intrathecal 5-HT (20-100 micrograms, 10 microliter) increased activity in renal nerves (mean change for 50 micrograms dose 157% +/- 39). At higher doses of 5-HT the initial excitatory response was followed by inhibition 64% +/- 15. Intrathecally, alpha methyl 5-HT (10-400 micrograms) mimicked only the inhibitory action of 5-HT in a dose-dependent manner. These inhibitions were completely antagonised by i.t. ketanserin (25-100 micrograms). Intrathecal 2 methyl 5-HT (10-200 micrograms) had little effect on renal nerve activity. Intrathecal 5 carboxyamidotryptamine (10-200 micrograms) had a more powerful excitatory action on renal nerve activity than did 5-HT. Intrathecally, 8 OH-DPAT (10-200 micrograms) was without effect. Neither the inhibitory action of 5-HT or the excitatory action was affected by i.t. ICS 205 930 (1-10 micrograms) or MDL 72222 (200 micrograms). It was concluded that the actions of 5-HT were within the spinal cord and that the inhibitory effect on sympathetic activity is mediated via a 5-HT2-like receptor whilst the receptors involved in the excitatory action of 5-HT are not M- or 5-HT3-like but appear to be more like the 5-HT1 subtype.

UI	MeSH Term	Description	Entries
D007278	Injections, Spinal	Introduction of therapeutic agents into the spinal region using a needle and syringe.	Injections, Intraspinal,Injections, Intrathecal,Intraspinal Injections,Intrathecal Injections,Spinal Injections,Injection, Intraspinal,Injection, Intrathecal,Injection, Spinal,Intraspinal Injection,Intrathecal Injection,Spinal Injection
D009433	Neural Inhibition	The function of opposing or restraining the excitation of neurons or their target excitable cells.	Inhibition, Neural
D011919	Rats, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.	August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
D011985	Receptors, Serotonin	Cell-surface proteins that bind SEROTONIN and trigger intracellular changes which influence the behavior of cells. Several types of serotonin receptors have been recognized which differ in their pharmacology, molecular biology, and mode of action.	5-HT Receptor,5-HT Receptors,5-Hydroxytryptamine Receptor,5-Hydroxytryptamine Receptors,Receptors, Tryptamine,Serotonin Receptor,Serotonin Receptors,Tryptamine Receptor,Tryptamine Receptors,Receptors, 5-HT,Receptors, 5-Hydroxytryptamine,5 HT Receptor,5 HT Receptors,5 Hydroxytryptamine Receptor,5 Hydroxytryptamine Receptors,Receptor, 5-HT,Receptor, 5-Hydroxytryptamine,Receptor, Serotonin,Receptor, Tryptamine,Receptors, 5 HT,Receptors, 5 Hydroxytryptamine
D001794	Blood Pressure	PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.	Systolic Pressure,Diastolic Pressure,Pulse Pressure,Pressure, Blood,Pressure, Diastolic,Pressure, Pulse,Pressure, Systolic,Pressures, Systolic
D002404	Catheterization	Use or insertion of a tubular device into a duct, blood vessel, hollow organ, or body cavity for injecting or withdrawing fluids for diagnostic or therapeutic purposes. It differs from INTUBATION in that the tube here is used to restore or maintain patency in obstructions.	Cannulation,Cannulations,Catheterizations
D002408	Catheters, Indwelling	Catheters designed to be left within an organ or passage for an extended period of time.	Implantable Catheters,In-Dwelling Catheters,Catheter, In-Dwelling,Catheter, Indwelling,Catheters, In-Dwelling,In Dwelling Catheters,In-Dwelling Catheter,Indwelling Catheter,Indwelling Catheters
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
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
D012701	Serotonin	A biochemical messenger and regulator, synthesized from the essential amino acid L-TRYPTOPHAN. In humans it is found primarily in the central nervous system, gastrointestinal tract, and blood platelets. Serotonin mediates several important physiological functions including neurotransmission, gastrointestinal motility, hemostasis, and cardiovascular integrity. Multiple receptor families (RECEPTORS, SEROTONIN) explain the broad physiological actions and distribution of this biochemical mediator.	5-HT,5-Hydroxytryptamine,3-(2-Aminoethyl)-1H-indol-5-ol,Enteramine,Hippophaine,Hydroxytryptamine,5 Hydroxytryptamine